GT750 Starter Clutch Housing

water cooled · Post by **water cooled** » Fri May 29, 2009 7:25 am

Last night was the worst trying to work in the garage. It was so humid, my glasses kept sliding off my head and nothing I touched seemed to work out...so I stopped, grabbed a beer and watched the CAV's game.

I've tried several times to correct a leak on the lowere edge of the Starter Clutch housing. New gasket, new ss screws, checked to see if the screws were bottoming out, retapped all the holes and found RTV in the back of them, reassemble and tightened the screws...no change. Still drips oil.

Tech Inspection wont let that fly and I dont know what else to try to get that housing to seal against the crank cases....

My water pump is getting worse too but I have some seals on the way and may need to rebuild the pump.

Suzukidave · Post by **Suzukidave** » Fri May 29, 2009 7:52 am

Kevin , if the oil seal on the point cam drive fails the tranny oil can leak past and find its way to the drain at the bottom of the starter clutch cover , just a guess .

bighole · Post by **bighole** » Fri May 29, 2009 8:02 am

I had the same problem and that was the solution. The seal is still easily cross refrenced, you don't need to go to the microfiche.
As long as you are in there, check the point shaft bearings also. I had one that went bad causing the shaft to wiggle. Oil was leaking past the seal because it was wiggling plus it was causing erratic ignition. That bearing is also easily cross refrenced.

-John

water cooled · Post by **water cooled** » Fri May 29, 2009 8:09 am

Hi Dave,

A few months back, I removed the breaker cam bearings and plugged the shaft-thru hole with a 35mm freeze plug. The leak is occuring between the main starter clutch housing and the two engine cases. In fact, I can see the drips form only while the engine is running and it develops right on the housing gasket, then runs over to one of the case bolts and drips from there...all the surfaces are clean...how flat they are is anyones guess. I've read that I can use some type of compound on a plate glass to get a flat surface. That would work for the aluminum housing, not so easy for the case surfaces.

Kevin

Suzukidave · Post by **Suzukidave** » Fri May 29, 2009 8:24 am

Being the leak only happens while the engine is running still leads me to think it still may be leaking past the freeze plug . Can you check that seal around the freeze plug while the engine is running ?

water cooled · Post by **water cooled** » Fri May 29, 2009 8:27 am

Dave, John,

Here are some images that I took at the time. BTW, I saved the bearings, keeper and seal if anyone needs them. The bearings were gently pressed out so I dont know if they are still useable or not but I will not need them for anything.

You can see in the last picture, the light blue gasket...that is the surface where the leak is occuring except on the lower edge of the housing. It runs over to that case bolt and forms there making it look like the leak is from the case bolt.

water cooled · Post by **water cooled** » Fri May 29, 2009 8:29 am

Yep...did that already and no oil is getting past the freeze plug...

Suzukidave · Post by **Suzukidave** » Fri May 29, 2009 8:43 am

Oh .. i see where you are talking about now , thats so odd that it only leaks when the engine is running ?

water cooled · Post by **water cooled** » Fri May 29, 2009 8:48 am

I know...it is odd because there really isnt a lot of pressure from the case. I tightened the ss housing screws to a point where any more tightening causes the drips to get bigger. Thats a brand new gasket.

All I can think is to take it all apart and re clean the surfaces. I dont know if there is any type of spray "form-a-gasket" that might enhance the sealing...I've not seen anything like that before...just the RTV stuff and I dont want to do that.

Suzukidave · Post by **Suzukidave** » Fri May 29, 2009 8:57 am

If you have a tube of Suzuki / Yamaha bond #3 a smear of that on both sides of the gasket couldnt hurt .

tz375 · Post by **tz375** » Fri May 29, 2009 9:21 am

kevin,

That sounds like the case is slightly distorted. Try to run a smooth 10" file across it and you'll probably see the low spots after one pass. Draw file it it carefully or stick a sheet of wet and dry on a flat surface and use kerosene or WD40 as a lubricant/cutting oil.

Another way to look for the low spot is to remove teh cover and gasket and wipe it all clean. Smear on the thinnest coating of bearing blue to one surface and press them together by hand. You'll be able to see where it was squeezed between the matching surfaces and where they don't touch.

If you don't have bearing blue try a non setting gasket goo like Hylomar.

if it turns out to be a low spot in the crankcase, apply a coating of silastic to that surface and fit the gasket.

We had a similar problem on a TZ and after trying all of the above found a screw that was 2mm too long and it was bottoming out. We found it by replacing the cover without a gasket and fitting one screw at a time to see it it clamped the case, and one of them left the case slightly loose.

water cooled · Post by **water cooled** » Fri May 29, 2009 9:38 am

ok...I'll give these options a try at lunch and see what I can learn.

Thanks guys...