Author Topic: Oil Stain Midway Down from Head on Engine  (Read 1546 times)

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42indian

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Oil Stain Midway Down from Head on Engine
« on: November 27, 2008, 05:28:35 PM »
My 1978 CB750 has a stain on the fins abou 1/2 way down from the top of the engine head.  Is this a leak in the head gasket or a different gasket?

To fix this what do you need to remove?
John

Offline 05c50

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Re: Oil Stain Midway Down from Head on Engine
« Reply #1 on: November 27, 2008, 05:52:19 PM »
Is it leaking on the front of the engine (near the exhaust) or on the side ? A picture would be very helpful.

........Paul
Wear a helmet,the life you save may be your own.Ask me how I know.               CB650C,CB550F,GL1000,CB750A

Offline Shenanigans

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Re: Oil Stain Midway Down from Head on Engine
« Reply #2 on: November 27, 2008, 06:34:01 PM »
Most likely the head gasket or leaking from the oil passages. Any head work needs the engine to be dropped out of the frame. Unless you buy a kit like this http://forums.sohc4.net/index.php?topic=43144.0;topicseen
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Offline CB750F2

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Re: Oil Stain Midway Down from Head on Engine
« Reply #3 on: November 28, 2008, 02:56:10 AM »
The most likely sources of your leak are:-
        Pucks under the cam towers
        Valve cover gasket
        Studs that hold the cam tower bearing shells. Oil can leak down via the threads.
Pat
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Offline OldSchool_IsCool

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Re: Oil Stain Midway Down from Head on Engine
« Reply #4 on: December 02, 2008, 08:22:29 PM »
To zero in on the leak, clean the fins, let them dry, spray them down with foot powder (yes, foot powder) then run the engine.  The foot powder will turn black at the site of the leak.

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Offline ghost

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Re: Oil Stain Midway Down from Head on Engine
« Reply #5 on: December 02, 2008, 08:54:50 PM »
hey that almost looks like my engine, except there's not nearly enough oil there to be mine. i know, bad ghost. it's almost time to change those gaskits, just as soon as it actually snows here.
1980 cb650c first bike i owned now the wife's ride.           1982 xv920j virago, bike i learned to ride on rescued it from a 13 year coma (sitting in the shed) now she runs beautifully and rides like a dream.