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Complete engine rebuild Suzuki GT750-A (MA)

Installed the gear position switch for the third time, sadly still leaking gearbox oil. We will solve this problem of course. We don't want leaking rebuild engines.
Installed the gear position switch for the third time, sadly still leaking gearbox oil. We will solve this problem of course. We don't want leaking rebuild engines.
We screwed in the threaded bushing with strong lock-tite.
We screwed in the threaded bushing with strong lock-tite.
We screwed in the threaded bushing with strong lock-tite.
We made M8 threading on the threading bushings. Then we screwed in the threaded bushing with strong lock-tite.
We made M8 threading on the threading bushings. Then we screwed in the threaded bushing with strong lock-tite.
Who did this bad repair? There is no material to do a new repair. So what to do?
Who did this bad repair? There is no material to do a new repair. So what to do?
Gearbox oil is dripping between the engine and the gear psoition switch.
Gearbox oil is dripping between the engine and the gear psoition switch.
Gearbox oil is dripping between the engine and the gear psoition switch.
It'sreally leaking a lot of gearbox oil.
It'sreally leaking a lot of gearbox oil.
Sadly we can't do a FIRST RUN for now, the conditions are not OK. We have a severe gearbox oil leak at the gear position switch. Why? In the can gearbox oil after to days.
Sadly we can't do a FIRST RUN for now, the conditions are not OK. We have a severe gearbox oil leak at the gear position switch. Why? In the can gearbox oil after to days.
Installing the engine again in the frame of the bike. We can go on and install all parts on the bike for doing the FIRST RUN.
Installing the engine again in the frame of the bike. We can go on and install all parts on the bike for doing the FIRST RUN.
Finished the engine.
Finished the engine.
Finished the engine.
Finished the engine.
Finished the engine.
Finished the engine.
Assembling the engine. Installing the barrel: All the pistons on the right place? Newly bored barrel to 2mm oversized pistons.
Assembling the engine. Installing the barrel: All the pistons on the right place? Newly bored barrel to 2mm oversized pistons.
Assembling the engine.
Assembling the engine.
Assembling the engine.
Assembling the engine.
Assembling the engine.
Assembling the engine.
Assembling the engine.
Assembling the engine.
Assembling the engine.
A big hole where there should be threading. (ONE)
A big hole where there should be threading. (ONE)
What's happening here, the threading bushing is pulled out. Who repaired this, why isn't there any threading on the bushing. This is the reason why we pulled out the threading bushing.
What's happening here, the threading bushing is pulled out. Who repaired this, why isn't there any threading on the bushing. This is the reason why we pulled out the threading bushing.
Checking if the seals are running free in the engine, YES THIS IS A MUST!
Checking if the seals are running free in the engine, YES THIS IS A MUST!
Checking if the seals are running free in the engine, YES THIS IS A MUST!
Checking if the seals are running free in the engine, YES THIS IS A MUST!
Checking if the seals are running free in the engine, YES THIS IS A MUST!
Hah, a fresh rebuild cranckshaft arrived.
Hah, a fresh rebuild cranckshaft arrived.
Cleaning the engine before we rebuild the engine again.
Cleaning the engine before we rebuild the engine again.
Cleaning the engine before we rebuild the engine again.
Shattered pieces small-end bearing.
Shattered pieces small-end bearing.
Replace the cranckshaft mainbearing, connection rod, big-end bearing an small-end bearing.
Replace the cranckshaft mainbearing, connection rod, big-end bearing an small-end bearing.
Open the engine again, of course with this damage you need to rebuild the cranckshaft again. There are to many broken peaces inside.
Open the engine again, of course with this damage you need to rebuild the cranckshaft again. There are to many broken peaces inside.
Bearing needles only, damaged thrust washers too.
Bearing needles only, damaged thrust washers too.
Just the right side of the small-end needle bearing cage was left over.
Just the right side of the small-end needle bearing cage was left over.
Take a look at the small-end bearing, there are only needles left. Where is the bearing needle cage?
Take a look at the small-end bearing, there are only needles left. Where is the bearing needle cage?
Lifting the cilinderhead, the right cilinder has had detonating combustion.
Lifting the cilinderhead, the right cilinder has had detonating combustion.
Engine OUT!
Engine OUT!
Discovered a wrong secured front sprocket. The secure washer will NOT do it's job: To keep the hex nut on it's place.
Discovered a wrong secured front sprocket. The secure washer will NOT do it's job: To keep the hex nut on it's place.
Inspecting the ignition side of the engine before we remove the complete engine. Found nothing what could caused the ratling sounds.
Inspecting the ignition side of the engine before we remove the complete engine. Found nothing what could caused the ratling sounds.
The GT750 with engine problems still there.
The GT750 with engine problems still there.
Closing the engine with the clutch cover, using a new gasket.
Closing the engine with the clutch cover, using a new gasket.
Assembled the complete clutch again and made a test ride.
Assembled the complete clutch again and made a test ride.
We inspected everything, didn't find anything. We replaced the large clutch needle bearing for a new one.
We inspected everything, didn't find anything. We replaced the large clutch needle bearing for a new one.
We inspected everything, didn't find anything.
We inspected everything, didn't find anything.
After we did the carburettors the detonating sounds were gone, SADLY we heard a loud ratling sound in the engine when we went to 4000revs. We thought it was located behind the clutch cover, so we inspected this side of the engine.
After we did the carburettors the detonating sounds were gone, SADLY we heard a loud ratling sound in the engine when we went to 4000revs. We thought it was located behind the clutch cover, so we inspected this side of the engine.
After we did the carburettors the detonating sounds were gone, SADLY we heard a loud ratling sound in the engine when we went to 4000revs.
After we did the carburettors the detonating sounds were gone, SADLY we heard a loud ratling sound in the engine when we went to 4000revs.
DANGEROUS throttle cables, this is not the way to drive a motorbike, your gas throttle will not go back automaticaly to idle.
DANGEROUS throttle cables, this is not the way to drive a motorbike, your gas throttle will not go back automaticaly to idle.
DANGEROUS throttle cables, this is not the way to drive a motorbike, your gas throttle will not go back automaticaly to idle.
So we cleaned all the carburettors thouroughly and rebuild and adjusted these carburettors afterwards. after
So we cleaned all the carburettors thouroughly and rebuild and adjusted these carburettors afterwards. after
Bad adjusted floats in the carburettors, one didn't close the float needle at all.
Bad adjusted floats in the carburettors, one didn't close the float needle at all.
A lot of rust, this caused clogged jets, running lean and the result: a detonating engine.
A lot of rust, this caused clogged jets, running lean and the result: a detonating engine.
And when you have rust in your gas tank, it is sure your carburettors will be clogged.
And when you have rust in your gas tank, it is sure your carburettors will be clogged.
The client did some cleaning on the gas tank, sadly he didn't seal the tank. So again a lot of rust was running trough the opetcock.
The client did some cleaning on the gas tank, sadly he didn't seal the tank. So again a lot of rust was running trough the opetcock.
Draining the gas tank for repairing the petcock. Duh........ a lot of rust came out of the gas tank.
Draining the gas tank for repairing the petcock. Duh........ a lot of rust came out of the gas tank.
The leaking petcock, when you have bad adjusted carburettors gas will run in the cilinders.
The leaking petcock, when you have bad adjusted carburettors gas will run in the cilinders.
FRESH REBUILD ENGINE DAMAGED WARNING.
FRESH REBUILD ENGINE DAMAGED WARNING.
SITE UPDATE: FRESH REBUILD ENGINE DAMAGED WARNING.
SITE UPDATE: FRESH REBUILD ENGINE DAMAGED WARNING.
Just for tagging: Motor revisie GT750 GT550 GT380 T20 T500 GT2500 T350 krukas revisie cilinder boren en honen polijsten onderdelen waterpomp zuigers onderhoud reparatie vervanging
Just for tagging: Motor revisie GT750 GT550 GT380 T20 T500 GT2500 T350 krukas revisie cilinder boren en honen polijsten onderdelen waterpomp zuigers onderhoud reparatie vervanging
> UPDATE 26-03-2024: Impression of a total rebuild GT750 engine.
> UPDATE 26-03-2024: Impression of a total rebuild GT750 engine.
Impression of a total rebuild GT750 engine.
Impression of a total rebuild GT750 engine.
Impression of a total rebuild GT750 engine.
Impression of a total rebuild GT750 engine.
Impression of a total rebuild GT750 engine.
Impression of a total rebuild GT750 engine.
Impression of a total rebuild GT750 engine.
Checking the oil pump: Bench check for checking the "production" of enough oil. After that do the oil pump test on a running engine. Oil pump PASSED the test, even the oil pump is tempered with.
Checking the oil pump: Bench check for checking the "production" of enough oil. After that do the oil pump test on a running engine. Oil pump PASSED the test, even the oil pump is tempered with.
Do you recognize the LIQUID COOLED on this engine? Right side.
Do you recognize the LIQUID COOLED on this engine? Right side.
Do you recognize the LIQUID COOLED on this engine? Left side.
Do you recognize the LIQUID COOLED on this engine? Left side.
Back view on the barrel, elektrical starter cover is installed.
Back view on the barrel, elektrical starter cover is installed.
Top view on the cilinderhead. See the stainless steel bolts, very nice.
Top view on the cilinderhead. See the stainless steel bolts, very nice.
Barrel and cilinderhead installed and all the bolts are torqued in the proper way and sequence. Always close the inlet and outlet of the barrel.
Barrel and cilinderhead installed and all the bolts are torqued in the proper way and sequence. Always close the inlet and outlet of the barrel.
Barrel and cilinderhead installed and all the bolts are torqued in the proper way and sequence.
Barrel and cilinderhead installed and all the bolts are torqued in the proper way and sequence.
Barrel and cilinderhead installed and all the bolts are torqued in the proper way and sequence. We use stainless steel M10 and M8 bolts.
Barrel and cilinderhead installed and all the bolts are torqued in the proper way and sequence. We use stainless steel M10 and M8 bolts.
Barrel installed front picture.
Barrel installed front picture.
Barrel installed.
Barrel installed.
Before lowering the barrel in total ALWAYS check if the four O-rings are still in it's place.
Before lowering the barrel in total ALWAYS check if the four O-rings are still in it's place.
CHECK if all three oil channels to the barrel are open in the footer gasket.
CHECK if all three oil channels to the barrel are open in the footer gasket.
CHECK if all three oil channels to the barrel are open in the footer gasket.
Left and Center pistons close-up.
Left and Center pistons close-up.
Right and Center pistons close-up.
Right and Center pistons close-up.
All p[istons installed and inspected for the right installation.
All p[istons installed and inspected for the right installation.
ALL piston circlips (L-C-R) are inspected and photograhped for the right installation in it's seat.
ALL piston circlips (L-C-R) are inspected and photograhped for the right installation in it's seat.
ALL piston circlips (L-C-R) are inspected and photograhped for the right installation in it's seat.
Prepairing the cilinderhead for installetion, so assemble the thermostat housing.
Prepairing the cilinderhead for installetion, so assemble the thermostat housing.
Everything installed below the elektrical starter cover.
Everything installed below the elektrical starter cover.
The repaired oil line, take a look at the outer LH check-valve, the banjo only connection is replaced bij a real check-valve. Yes this is possible, there is enough space near the elektrical starter.
The repaired oil line, take a look at the outer LH check-valve, the banjo only connection is replaced bij a real check-valve. Yes this is possible, there is enough space near the elektrical starter.
Dias-assembling the in-line check-valve, the spring was to short and caused oil leakage.
Dias-assembling the in-line check-valve, the spring was to short and caused oil leakage.
As you see the oil line has no o2stroke oil after the hangtest. You have to repair the oil lines when they lose oil, this because you will damage your engine.
As you see the oil line has no o2stroke oil after the hangtest. You have to repair the oil lines when they lose oil, this because you will damage your engine.
The oil lines FAILED the hangtest, so we had to repair the outer LH check-valve. Sadly this is oil line has the IN-LINE check-valve, we experienced that after repairing this check-valve it always will leak again. So we installed the check-valve banjo.
The oil lines FAILED the hangtest, so we had to repair the outer LH check-valve. Sadly this is oil line has the IN-LINE check-valve, we experienced that after repairing this check-valve it always will leak again. So we installed the check-valve banjo.
Installing the gear position switch.
Installing the gear position switch.
Yes the thermostat opens, so ready to install.
Yes the thermostat opens, so ready to install.
Be sure that the thermostat works fine, so testing in boiling water. Should open the thermostat.
Be sure that the thermostat works fine, so testing in boiling water. Should open the thermostat.
Installing the generator.
Installing the generator.
Adjusting the ignition points as in the manual. Don't forget to lubricatie the small felt pad.
Adjusting the ignition points as in the manual. Don't forget to lubricatie the small felt pad.
> UPDATE 23-03-2024: A lot of hard work to complete an engine of a GT750. But it feels good.
> UPDATE 23-03-2024: A lot of hard work to complete an engine of a GT750. But it feels good.
A lot of hard work to complete an engine of a GT750. But it feels good.
A lot of hard work to complete an engine of a GT750. But it feels good.
A lot of hard work to complete an engine of a GT750. But it feels good.
A lot of hard work to complete an engine of a GT750. But it feels good.
A lot of hard work to complete an engine of a GT750. First thing to do is to install al elektrical stuff and routing underneath the engine. At last we will install the pistons and tthe barrel.
A lot of hard work to complete an engine of a GT750. First thing to do is to install al elektrical stuff and routing underneath the engine. At last we will install the pistons and tthe barrel.
Installed clutch cover.
Installed clutch cover.
Installed gasket.
Installed gasket.
Torqued and marked M8 clutch spring bolts.
Torqued and marked M8 clutch spring bolts.
All clutch plates installed.
All clutch plates installed.
Fresh new clutch plates and new steel rings.
Fresh new clutch plates and new steel rings.
Woh, what has happened here, something is missing on the steel ring. This clutch basket was installed before the rebuild. We don't recommend anyone to use this. This because the steel ring can go of during a ride. What then happens you can guess. In case of you can rebuild the engine again. As the older types didn't have a steel ring at all i removed the rest of this broken steel ring.
Woh, what has happened here, something is missing on the steel ring. This clutch basket was installed before the rebuild. We don't recommend anyone to use this. This because the steel ring can go of during a ride. What then happens you can guess. In case of you can rebuild the engine again. As the older types didn't have a steel ring at all i removed the rest of this broken steel ring.
Clutch bearing ring, the edged side to the gearbox bearing.
Clutch bearing ring, the edged side to the gearbox bearing.
Nope not with these garbage, we install a new set of clutch polates and steel plates. What you see on this photo is when you parked the GT750 for over 20years.
Nope not with these garbage, we install a new set of clutch polates and steel plates. What you see on this photo is when you parked the GT750 for over 20years.
Don't forget the shim behind the large ring.
Don't forget the shim behind the large ring.
Dynamo rotor installed on the cranckshaft. The clutch has to be installled.
Dynamo rotor installed on the cranckshaft. The clutch has to be installled.
Ignition engine cover installed.
Ignition engine cover installed.
Starterclutch and the nylon waterpump gear installed already.
Starterclutch and the nylon waterpump gear installed already.
Be sure that the Woodruff key is installed.
Be sure that the Woodruff key is installed.
Inspection of the cranckshaft seals if they don't touch the cranckshaft, by using a thin ruler.
Inspection of the cranckshaft seals if they don't touch the cranckshaft, by using a thin ruler.
Inspection of the cranckshaft seals if they don't touch the cranckshaft, by using a thin ruler.
Inspection of the cranckshaft seals if they don't touch the cranckshaft, by using a thin ruler.
> UPDATE 22-03-2024: Secure plate and shifting plates installed and secured with locktite.
> UPDATE 22-03-2024: Secure plate and shifting plates installed and secured with locktite.
Primairy and Secundairy GEAR shafts installed in the lower engine casing.
Primairy and Secundairy GEAR shafts installed in the lower engine casing.
Al gearbox parts, kickstarter, oil pump shaft, waterpump active shaft and the crankshaft installed in de lower engine casing. The cranckshaft rebuilder did a good job again by making this super cranckshaft. A former rebuilder MIXED UP older an newer cranckshaft parts in this cranckshaft as a total mess-up.
Al gearbox parts, kickstarter, oil pump shaft, waterpump active shaft and the crankshaft installed in de lower engine casing. The cranckshaft rebuilder did a good job again by making this super cranckshaft. A former rebuilder MIXED UP older an newer cranckshaft parts in this cranckshaft as a total mess-up.
Al fine with the other gear. The "dogs" fit very well to eachother.
Al fine with the other gear. The "dogs" fit very well to eachother.
The "dogs" are looking fine now, this 3rd gear can be used again.
The "dogs" are looking fine now, this 3rd gear can be used again.
Total dis-assembled secundiary gear shaft. This for cleaning and checking and for repairing the 3rd gear.
Total dis-assembled secundiary gear shaft. This for cleaning and checking and for repairing the 3rd gear.
Totally worn "dogs" on this 3rd gear, we have to do something. Otherwise you will gearbox problems during the gear shifting to the 3rd gear.
Totally worn "dogs" on this 3rd gear, we have to do something. Otherwise you will gearbox problems during the gear shifting to the 3rd gear.
The 3rd gear on this shaft has been hot, no idea how this have happened. The gear looks pretty good so we have to use gear shaft again.
The 3rd gear on this shaft has been hot, no idea how this have happened. The gear looks pretty good so we have to use gear shaft again.
Always to be forgotten, be sure these two screws are fastened.
Always to be forgotten, be sure these two screws are fastened.
> UPDATE 19-03-2024: Installing the gear shifting cam, alwaya use some oil to lubricate, BEFORE the engine is being closed we test the gearbox by shifting the gears.
> UPDATE 19-03-2024: Installing the gear shifting cam, alwaya use some oil to lubricate, BEFORE the engine is being closed we test the gearbox by shifting the gears.
Inside the GT750 engine, the shaft with gear for the waterpomp and the waterpump oil/water by-pass.
Inside the GT750 engine, the shaft with gear for the waterpomp and the waterpump oil/water by-pass.
Almost ready for closing the waterpump housing cover.
Almost ready for closing the waterpump housing cover.
Installed and secured the complete waterpump.
Installed and secured the complete waterpump.
Before installing the waterpump, be sure all surfaces are CLEAN and don't have any corrosion. In case of any corrosion the waterpump will leak oil or coolant.
Before installing the waterpump, be sure all surfaces are CLEAN and don't have any corrosion. In case of any corrosion the waterpump will leak oil or coolant.
Upper engine case cleaned and painted with heat resistant engine paint.
Upper engine case cleaned and painted with heat resistant engine paint.
Upper engine case cleaned and painted with heat resistant engine paint.
Polished GT750 engine parts. Yes a lot of work.
Polished GT750 engine parts. Yes a lot of work.
Take a look at the seal (the seal between the Left and Center cilinder) totaly destroyed. It's for sure the GT750 engine will run very bad.
Take a look at the seal (the seal between the Left and Center cilinder) totaly destroyed. It's for sure the GT750 engine will run very bad.
Old and worn cranckshaft stuff.
Old and worn cranckshaft stuff.
As you can see two newer type connecting rods and one older type of connecting rod. Replaced te older type connecting rod for a newer type.
As you can see two newer type connecting rods and one older type of connecting rod. Replaced te older type connecting rod for a newer type.
Cranckshaft totaly dis-assembled for the rebuild. A problem discovered: A formar rebuilder MIXED UP early GT750 parts (J-K) with later parts. The early types of the cranckwebs are 1mm thicker then the later types.
Cranckshaft totaly dis-assembled for the rebuild. A problem discovered: A formar rebuilder MIXED UP early GT750 parts (J-K) with later parts. The early types of the cranckwebs are 1mm thicker then the later types.
> SITE UPDATE 17-11-2023:The metal housing of the gear position switch isn't usable any more because it is damaged by a broken chain in the past, the engine surface of the gear position switch isn't flat anymore and it is wobbling on it's seat on the engine: So TOTALL LOSS! Sadly just that part is hard to find and when you find one very expensive. We have to replace this part otherwise you will have severe engine oil leakage!
> SITE UPDATE 17-11-2023:The metal housing of the gear position switch isn't usable any more because it is damaged by a broken chain in the past, the engine surface of the gear position switch isn't flat anymore and it is wobbling on it's seat on the engine: So TOTALL LOSS! Sadly just that part is hard to find and when you find one very expensive. We have to replace this part otherwise you will have severe engine oil leakage!
The solderings are done bad..................
The solderings are done bad..................
Both screw holes are broken................
Both screw holes are broken................
Remember this some photo's ago? Check........
Remember this some photo's ago? Check........
If you want the waterpump not to leak oil or coolant again, you have to clean every part of the waterpump.
If you want the waterpump not to leak oil or coolant again, you have to clean every part of the waterpump.
If you want the waterpump not to leak oil or coolant again, you have to clean every part of the waterpump.
If you want the waterpump not to leak oil or coolant again, you have to clean every part of the waterpump.
Repairing and rebuilding the waterpump. The waterpump leaked coolant that's for sure. Repairing with sealant is not adequate. Repairing and rebuilding a waterpomp is the right way. Everything inside the waterpump was worn: Inside seal (oil) and the mechanical seal (coolant) replaced by new and refurbished parts.
Repairing and rebuilding the waterpump. The waterpump leaked coolant that's for sure. Repairing with sealant is not adequate. Repairing and rebuilding a waterpomp is the right way. Everything inside the waterpump was worn: Inside seal (oil) and the mechanical seal (coolant) replaced by new and refurbished parts.
Try-out if the cranckshaft seal SEAT is OK after the repair. Looks fine now, the cranckshaft bearing and the seal fit in a proper way.
Try-out if the cranckshaft seal SEAT is OK after the repair. Looks fine now, the cranckshaft bearing and the seal fit in a proper way.
Try-out if the cranckshaft seal SEAT is OK after the repair. Looks fine now, the cranckshaft bearing and the seal fit in a proper way.
Reconstruction of the cranckshaft seal SEAT upper engine, which is worn due to a damaged cranckshaft seal.
Reconstruction of the cranckshaft seal SEAT upper engine, which is worn due to a damaged cranckshaft seal.
< SITE UPDATE 17-11-2023: Reconstruction of the cranckshaft seal SEAT lower engine, which is worn due to a damaged cranckshaft seal.
< SITE UPDATE 17-11-2023: Reconstruction of the cranckshaft seal SEAT lower engine, which is worn due to a damaged cranckshaft seal.
UPDATE 12-11-2023: As you can see: 11mm hardened sealant. The UPPER engine casing is NOT the place for having or getting ANY sealant. Why? The LOWER engine casing is the base to start with the rebuild. The LOWER engine casings surfaces get the sealant for closing the engine itself. I think this can be sabotage?!
UPDATE 12-11-2023: As you can see: 11mm hardened sealant. The UPPER engine casing is NOT the place for having or getting ANY sealant. Why? The LOWER engine casing is the base to start with the rebuild. The LOWER engine casings surfaces get the sealant for closing the engine itself. I think this can be sabotage?!
Almost everthing out. It is some silicon sealant which is squised in the (2stroke) OIL channel. For everyone it is crystal clear that the main cranckshaft bearing haven't got enough lubriction by the oil pump injection through this (2stroke) OIL channel. And when this main cranckshaft bearing did't get enough 2 stroke oil, the BIG-end of this cilinder didn't get enough 2stroke oil to!
Almost everthing out. It is some silicon sealant which is squised in the (2stroke) OIL channel. For everyone it is crystal clear that the main cranckshaft bearing haven't got enough lubriction by the oil pump injection through this (2stroke) OIL channel. And when this main cranckshaft bearing did't get enough 2 stroke oil, the BIG-end of this cilinder didn't get enough 2stroke oil to!
Poked almost everything from the clogged (2stroke) OIL channel out of it. Some 10mm is visible already.
Poked almost everything from the clogged (2stroke) OIL channel out of it. Some 10mm is visible already.
So we try to poke the (2stroke) OIL channel open from above of the upper engine casing. The first mm is visiable already. But on poking i feel it's still sticky in the (2stroke) OIL channel.
So we try to poke the (2stroke) OIL channel open from above of the upper engine casing. The first mm is visiable already. But on poking i feel it's still sticky in the (2stroke) OIL channel.
This was a very good eye test today: When busy cleaning the upper engine casing! Saw the clogged (2stroke) OIL channel in the seat of the cranckshaft bearing between MID and LEFT cilinder.
This was a very good eye test today: When busy cleaning the upper engine casing! Saw the clogged (2stroke) OIL channel in the seat of the cranckshaft bearing between MID and LEFT cilinder.
> UPDATE 12-11-2023: Cleaning upper and lower engine casings for repair and of course for rebuild. Always start with a clean "work-space"!
> UPDATE 12-11-2023: Cleaning upper and lower engine casings for repair and of course for rebuild. Always start with a clean "work-space"!
UPDATE 11-11-2023: Cleaned and repaired GT750 barrel, ready foor the next rebore. Just need some polish.
UPDATE 11-11-2023: Cleaned and repaired GT750 barrel, ready foor the next rebore. Just need some polish.
Cleaned and repaired GT750 barrel, ready for the next rebore. Just need some polish.
Cleaned and repaired GT750 barrel, ready for the next rebore. Just need some polish.
One of the former owners of this GT750 has used WATER as coolant in the engine. Using water as coolant will always give severe corrosion. Corrosion damage, we hope it will not leak coolant.
One of the former owners of this GT750 has used WATER as coolant in the engine. Using water as coolant will always give severe corrosion. Corrosion damage, we hope it will not leak coolant.
One of the former owners of this GT750 has used WATER as coolant in the engine. Using water as coolant will always give severe corrosion. Corrosion damage, we hope it will not leak coolant.
Cleaned bottom side of the barrel. Sadly found some traces of corrosion damage.
Cleaned bottom side of the barrel. Sadly found some traces of corrosion damage.
Inserting the helicoil M8, it's always tricky to get in the helicoil in the right way.
Inserting the helicoil M8, it's always tricky to get in the helicoil in the right way.
Inserting the helicoil M8, it's always tricky to get in the helicoil in the right way.
Threading the damaged and drilled out rest of the threads. Tapping thread to install the helicoil M8.
Threading the damaged and drilled out rest of the threads. Tapping thread to install the helicoil M8.
Threading the damaged and drilled out rest of the threads. Tapping thread to install the helicoil M8.
LEFT exhaust port: Both threads are OK.
LEFT exhaust port: Both threads are OK.
MIDDLE exhaust port: 1 thread (on the photo left) is damaged and need to be repaired. Thread damage due to using bolts because the aluminium of the barrel is very soft, today we use STUDS instead.
MIDDLE exhaust port: 1 thread (on the photo left) is damaged and need to be repaired. Thread damage due to using bolts because the aluminium of the barrel is very soft, today we use STUDS instead.
RIGHT exhaust port: 1 thread (on the photo left) is damaged and need to be repaired. Thread damage due to using bolts because the aluminium of the barrel is very soft, today we use STUDS instead.
RIGHT exhaust port: 1 thread (on the photo left) is damaged and need to be repaired. Thread damage due to using bolts because the aluminium of the barrel is very soft, today we use STUDS instead.
Reparing and refreshing the trhreads on top of the barrel, 2 threads, bolt nr.13 and bolt nr.18, in this photo the thread of bolt 18 is prepaired for the M8 helicoil.
Reparing and refreshing the trhreads on top of the barrel, 2 threads, bolt nr.13 and bolt nr.18, in this photo the thread of bolt 18 is prepaired for the M8 helicoil.
Reparing and refreshing the threads on top of the barrel, 2 threads, bolt nr.13 and bolt nr.18, in this photo the thread of bolt 15 is prepaired for the M8 helicoil.
Reparing and refreshing the threads on top of the barrel, 2 threads, bolt nr.13 and bolt nr.18, in this photo the thread of bolt 15 is prepaired for the M8 helicoil.
Reparing and refreshing the threads on top of the barrel, ON TOP 2 threads, bolt nr.13 and bolt nr.18, were to far gone and the bolts holes needed a helicoil. Drilling out the damaged thread holes. This is easier to do on this drilling machine.
Reparing and refreshing the threads on top of the barrel, ON TOP 2 threads, bolt nr.13 and bolt nr.18, were to far gone and the bolts holes needed a helicoil. Drilling out the damaged thread holes. This is easier to do on this drilling machine.
< UPDATE 11-11-2023: Cleaning, inspecting and reparing the GT750 barrel.
< UPDATE 11-11-2023: Cleaning, inspecting and reparing the GT750 barrel.
> UPDATE 10-11-2023: The upper casing looks better. It's a little worn out but usable.
> UPDATE 10-11-2023: The upper casing looks better. It's a little worn out but usable.
The upper casing looks better. It's a little worn out but usable.
The upper casing looks better. It's a little worn out but usable.
The new cranckshaft seal won't stay in it's seal seat, so we have to repair it anyway.
The new cranckshaft seal won't stay in it's seal seat, so we have to repair it anyway.
Another problem appeared on the disassembling of the engine: a worn out cranckshaft seal SEAT, due to the broken cranckshaft seal. (Upper engine case)
Another problem appeared on the disassembling of the engine: a worn out cranckshaft seal SEAT, due to the broken cranckshaft seal. (Upper engine case)
Repair of the M5 threading.
Repair of the M5 threading.
Inserting the M5 helicoil in the threaded hole, now you can use "stay sticky" locktite.
Inserting the M5 helicoil in the threaded hole, now you can use "stay sticky" locktite.
Make new (helicoil for M5) threading in the screw hole.
Make new (helicoil for M5) threading in the screw hole.
Due to rock solid screws one screw broke down. So this one have to be drilled out. It's hard to drill small screws out, so a M5 helicoil was needed.
Due to rock solid screws one screw broke down. So this one have to be drilled out. It's hard to drill small screws out, so a M5 helicoil was needed.
< UPDATE 10-11-2023: Removing the oil plate for cleaning the UPPER engine case. Again rock solid screws in this engine. Why, there was no corrosion, so i think someone used the wrong lock-tite.
< UPDATE 10-11-2023: Removing the oil plate for cleaning the UPPER engine case. Again rock solid screws in this engine. Why, there was no corrosion, so i think someone used the wrong lock-tite.
Refurbishing the waterpump, the waterpump shaft is usable again, seal and bearing needs to be replaced. The mechanical water seal is very worn and needs some repair.
Refurbishing the waterpump, the waterpump shaft is usable again, seal and bearing needs to be replaced. The mechanical water seal is very worn and needs some repair.
Again a lot of sealant inside the waterpump, the sealant is almost 5mm thick.
Again a lot of sealant inside the waterpump, the sealant is almost 5mm thick.
A lot of sealant and a mix of different bolts.
A lot of sealant and a mix of different bolts.
Not our job! Who did this? When you want to use washers, buy washers that will fit in a proper way. Take a look at the amount of used sealant to close the waterpump cover, did it leak? Yes it did, the waterpump was totaly worn, the inside seal was almost complete gone, the mechanical waterseal needs to be repaired.
Not our job! Who did this? When you want to use washers, buy washers that will fit in a proper way. Take a look at the amount of used sealant to close the waterpump cover, did it leak? Yes it did, the waterpump was totaly worn, the inside seal was almost complete gone, the mechanical waterseal needs to be repaired.
It looks like a professional repair. Sadly the threading bushings are not installed in the right way. Had to flatten the surfaces at the left because this threading bushing is not installed on 90ᵒ!
It looks like a professional repair. Sadly the threading bushings are not installed in the right way. Had to flatten the surfaces at the left because this threading bushing is not installed on 90ᵒ!
After heating the area up and drilling a hole in the M6 screw the screw could be removed. All 4 screw threading can be used without repair.
After heating the area up and drilling a hole in the M6 screw the screw could be removed. All 4 screw threading can be used without repair.
One screw to go! Rock solid not to be removed. Heating up all the metal for removing the last screw.
One screw to go! Rock solid not to be removed. Heating up all the metal for removing the last screw.
At least one screw could be removed without drilling or else.
At least one screw could be removed without drilling or else.
Removing the 4 ROCH SOLID M6 screws for the gear selection plates. Why rock solid?
Removing the 4 ROCH SOLID M6 screws for the gear selection plates. Why rock solid?
Overview of the engine at the back, notice the "bolt" in the upper left corner.
Overview of the engine at the back, notice the "bolt" in the upper left corner.
Was there in the past some oil leakage, What oil leakage? This is certainly not the right repair closing an oil bleader hole.
Was there in the past some oil leakage, What oil leakage? This is certainly not the right repair closing an oil bleader hole.
Seal between MID en LEFT defect, went into two pieces.
Seal between MID en LEFT defect, went into two pieces.
Seal between MID en LEFT defect, went into two pieces. REBUILD of the cranckshaft should have been done 23years ago?
Seal between MID en LEFT defect, went into two pieces. REBUILD of the cranckshaft should have been done 23years ago?
Seal between MID en LEFT defect, went into two pieces.
Seal between MID en LEFT defect, went into two pieces.
Seal between MID en LEFT defect, went into two pieces.
Broken chain engine damage. As it is at the ower side of the engine, it is not visable.
Broken chain engine damage. As it is at the ower side of the engine, it is not visable.
Broken chain engine damage. As it is at the ower side of the engine, it is not visable.
Just an overview of the ignition side of the engine. REMARK: The washer between the nylon waterpump gear and the circlip is missing.
Just an overview of the ignition side of the engine. REMARK: The washer between the nylon waterpump gear and the circlip is missing.
Almost done to split the engine.
Almost done to split the engine.
Clutch side of the engine.
Clutch side of the engine.
Clutch side of the engine. REMARK: The large washer is installed in the wrong way.
Clutch side of the engine. REMARK: The large washer is installed in the wrong way.
Clutch steel plates, covered with a lot of rust. These steelplates will be REPLACED by new ones. This because when we have done the rebuild and we re-use these steel plates, all rust will get in the engine and everything is getting dirty AGAIN.
Clutch steel plates, covered with a lot of rust. These steelplates will be REPLACED by new ones. This because when we have done the rebuild and we re-use these steel plates, all rust will get in the engine and everything is getting dirty AGAIN.
Very rusty steelplates.
Very rusty steelplates.
Duh..... missing parts of the gear indicator switch. The dis-assemble of this gear switch in this way is very dangerous, no you can get hurt, but the gear switch can be damaged and sometimes you can't use this part anymore because it will stay leaking oil. The gear switch is fragile, hard to find (if you can find one), and very EXPENSIVE.
Duh..... missing parts of the gear indicator switch. The dis-assemble of this gear switch in this way is very dangerous, no you can get hurt, but the gear switch can be damaged and sometimes you can't use this part anymore because it will stay leaking oil. The gear switch is fragile, hard to find (if you can find one), and very EXPENSIVE.
Cilinder bore damage, sadly it is in the compression area too.
Cilinder bore damage, sadly it is in the compression area too.
Barrel totaly worn........
Barrel totaly worn........
Damaged piston. Was there not enough 2 stroke oil for the right lubrication?
Damaged piston. Was there not enough 2 stroke oil for the right lubrication?
UPDATE 10-11-2023 - SUZUKI GT750-A COMPLETE ENGINE REBUILD (MA) IN PROGRESS
UPDATE 10-11-2023 - SUZUKI GT750-A COMPLETE ENGINE REBUILD (MA) IN PROGRESS
UPDATE 26-03-2024 - SUZUKI GT750-A COMPLETE ENGINE REBUILD (MA) FINISHED
UPDATE 26-03-2024 - SUZUKI GT750-A COMPLETE ENGINE REBUILD (MA) FINISHED

Parts for this bike

All parts Suzuki GT750

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