Bike is a '76 75/6. I replaced the clutch 3 years ago, along with the mainseal and oil pump o-ring and it rapidly developed a pretty significant oil leak. About 1 qt/400-600 miles. I replaced the mainseal and o-ring again thinking I had messed it up last time I went in there but the leak has not changed. Any suggestions would be welcome. I do not want to start an oil thread but I am running dino 20-50 in it.
Thanks
Dave
Stubborn oil leak
Stubborn oil leak
"You don't stop playing because you get old.
You get old because you stop playing."
You get old because you stop playing."
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Duane Ausherman
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Re: Stubborn oil leak
Does this oil leak show up as oil on the shelf?
Did you carefully inspect the sealing shoulder on the flywheel for a groove or other sign of roughness?
What does a leak down test show?
Do you have excessive crankcase pressure? Does it show burning oil (white smoke) when tested for rings at night riding conditions?
While this is very rare, it has been found on a few cases. A casting can be pourous and leak right out of the aluminum. To test it is not fun. One has to remove the transmission and flywheel. Clean it up really well and dust it with something visible. Then reassemble and run it for a very short time while looking for the first sign of drip. Remove all and see where the oil is coming from.
Did you carefully inspect the sealing shoulder on the flywheel for a groove or other sign of roughness?
What does a leak down test show?
Do you have excessive crankcase pressure? Does it show burning oil (white smoke) when tested for rings at night riding conditions?
While this is very rare, it has been found on a few cases. A casting can be pourous and leak right out of the aluminum. To test it is not fun. One has to remove the transmission and flywheel. Clean it up really well and dust it with something visible. Then reassemble and run it for a very short time while looking for the first sign of drip. Remove all and see where the oil is coming from.
Ask the Indians what happens when you don't control immigration.
Re: Stubborn oil leak
I doubt this is the case unless it has developed recently. The bike did not leak this way before I replaced the clutch, mainseal, oil pump o-ring in 2008.Duane Ausherman wrote:Does this oil leak show up as oil on the shelf?
Yes
Did you carefully inspect the sealing shoulder on the flywheel for a groove or other sign of roughness?
I cleaned it with paper towels and solvent and ran my finger over it. I did not make any more elaborate tests.
What does a leak down test show?
I haven't done one yet. There is no visible smoke on start up or a driving test and the plugs do not get fouled.
Do you have excessive crankcase pressure? Does it show burning oil (white smoke) when tested for rings at night riding conditions?
I do not know how to test for crankcase pressure. The reed valve is fairly new (<10K Miles) No smoke.
While this is very rare, it has been found on a few cases. A casting can be pourous and leak right out of the aluminum. To test it is not fun. One has to remove the transmission and flywheel. Clean it up really well and dust it with something visible. Then reassemble and run it for a very short time while looking for the first sign of drip. Remove all and see where the oil is coming from.
Thanks Duane.
"You don't stop playing because you get old.
You get old because you stop playing."
You get old because you stop playing."
Re: Stubborn oil leak
As Duane says, the flywheel is quite possibly the culprit.
Having a solid flywheel prevents running the bike with just the flywheel and looking for the exact source of the leak.
It sounds like a leak that will show fairly quickly using Duane's powder method.
Having a solid flywheel prevents running the bike with just the flywheel and looking for the exact source of the leak.
It sounds like a leak that will show fairly quickly using Duane's powder method.
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