Author Topic: 750 bad oil leak. pretty bad!  (Read 1158 times)

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Offline kopptl

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750 bad oil leak. pretty bad!
« on: September 18, 2009, 07:45:06 AM »
76 cb750. i replaced the mission cover the other day because it was pretty shot.  i used black gasket sealer on both sides and made sure avarything was uniformly tight. except now when im cranking it it starts pumping oil out of 3 boltsall 3 are right next to each other. the bolts are right on the of the cover right next to the alternator cover. any advice or suggestions will be a big help!

Offline Bob Wessner

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Re: 750 bad oil leak. pretty bad!
« Reply #1 on: September 18, 2009, 07:53:58 AM »
What is a mission cover?
We'll all be someone else's PO some day.

Offline 754

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Re: 750 bad oil leak. pretty bad!
« Reply #2 on: September 18, 2009, 07:55:56 AM »
 Order a new gasket,
then take the transMISSION cover off, and replace gasket.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Bob Wessner

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Re: 750 bad oil leak. pretty bad!
« Reply #3 on: September 18, 2009, 07:57:54 AM »
Ah.  ::) How short sighted of me. ;)
We'll all be someone else's PO some day.

Offline kopptl

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Re: 750 bad oil leak. pretty bad!
« Reply #4 on: September 18, 2009, 09:14:00 AM »
but i did replace it just the other day! i would rather not if i dont have to. any suggestions of stopping the leak??

Offline kopptl

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Re: 750 bad oil leak. pretty bad!
« Reply #5 on: September 18, 2009, 09:14:34 AM »
my mistake on only stating mission cover not transmision. sorry to confuse

Offline 754

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Re: 750 bad oil leak. pretty bad!
« Reply #6 on: September 18, 2009, 09:18:03 AM »
I dont know why, but it is actually called a  mission cover in the partsbook.

 If it leaking, you pretty well have to take it off & have a look.. if the gasket was new, something must be on one side, al;lowing oil out, sounds like..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline kopptl

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Re: 750 bad oil leak. pretty bad!
« Reply #7 on: September 18, 2009, 09:31:01 AM »
its not actually coming from the seems of the cover, its out out from around just 3 bolts like its bieng forced out. sounds kinda strange but thats whats happening
every hear of that happening??

Offline BVCB650

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Re: 750 bad oil leak. pretty bad!
« Reply #8 on: September 18, 2009, 09:37:12 AM »
its not actually coming from the seems of the cover, its out out from around just 3 bolts like its bieng forced out. sounds kinda strange but thats whats happening
every hear of that happening??




On my head cover, there are various bolts that have a "sealing washer" on them. Not all but some. They are just regular washers and darn near the same diameter as the bolt head. For some reason, they are supposed to stop an oil leak. I doubt they would work in your case, and I am not sure why they work in mine. I'd pull the cover back off and try to tell why the oil is coming out of the bolt holes. Maybe pay careful attention next time and make sure the holes are completely surrounded by gasket maker, and let it set up a bit before torquing down. The tendancy to over tighten a leak has cause many a stripped/broken bolt. Be careful.
1979 CB650, 25K miles, recently refurbished

Offline Bob Wessner

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Re: 750 bad oil leak. pretty bad!
« Reply #9 on: September 18, 2009, 10:06:50 AM »
I dont know why, but it is actually called a  mission cover in the partsbook.

Hmm, so it is. Never noticed that before.
We'll all be someone else's PO some day.