Author Topic: oil leak from case bolts?  (Read 748 times)

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Offline MasterChief750

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oil leak from case bolts?
« on: March 20, 2011, 07:08:13 PM »
ive got  slow, like super slow drip, i only noticed it because it dripped on my face, i didnt notice it until yesterday, it seems to be coming from bolts 5 and 1 on the torque sequence on the bottom of the motor. the motor hasnt been ran since rebuild but i didnt tear into the bottom end. none of the gaskets on the top end seem to be weeping. ive turned the motor over a few times but thats about it. should i try torquing these down? i know these two do squeeze the crankshaft and dont want to screw anything up. so i thought id ask first. and exactly how much to torque them down to. i posted it in my build thread but figured this would be a better place to do it.
1978 CB750 K - Project Red Headed Step Child
1976 CB750 K - Drag Bike
Some things i know, others i dont.
I AM THE STIG
Sam is THE STIG
he said i can be STIG3 tho

Offline bryanj

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Re: oil leak from case bolts?
« Reply #1 on: March 20, 2011, 11:28:29 PM »
Would help if you said which bike it is
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline wrenchmuch

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Re: oil leak from case bolts?
« Reply #2 on: March 21, 2011, 05:09:26 AM »
The torque spec is listed in the service manual (16.6-18.1 FT/LBS).
You can end up with leaks here if sealant wasn't applied to the flange faces around the crankshaft main bolts ,or if the flanges aren't pulled tightly together . You can take the bolt out , clean it with solvent , apply a non-hardening sealant to the underside of the head and both sides of the washer , and reinstall . This will probably seal the leak . If the bottom hasn't been apart , the bolt may have just loosened . Simply re-tightening may stop the leak. I assume your talking about a 750 listed in your avatar .
Mike
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Offline MasterChief750

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Re: oil leak from case bolts?
« Reply #3 on: March 21, 2011, 11:25:44 AM »
Yep 750. Didn't open the cases ill try tightening it. Im assuming if I take the bolt off ill end up with oil running all over the place
1978 CB750 K - Project Red Headed Step Child
1976 CB750 K - Drag Bike
Some things i know, others i dont.
I AM THE STIG
Sam is THE STIG
he said i can be STIG3 tho

Offline wrenchmuch

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Re: oil leak from case bolts?
« Reply #4 on: March 21, 2011, 03:48:25 PM »
A little oil might come out (2-3 thimbles) . This area isn't immersed in oil . It will only leak with the engine running . A small container will easily catch anything that comes out .
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