Author Topic: Oil on cooling fins, where's it coming from?  (Read 2036 times)

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Offline zoo mob

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Oil on cooling fins, where's it coming from?
« on: June 05, 2007, 01:04:59 PM »
My 73 750k3 has some oil that has been showing up on the cooling fins, what is the likely culprit? Should I be freaking out?
Andrew
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 1980 BMW R100T
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 1993 XR650L
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upperlake04

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Re: Oil on cooling fins, where's it coming from?
« Reply #1 on: June 05, 2007, 01:27:02 PM »
Quote
Should I be freaking out?

No, not yet ;D  Clean the engine, drive a bit and see where its coming from first. Then you will know if there is a reason or not to freak out.

Offline RRRToolSolutions

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Re: Oil on cooling fins, where's it coming from?
« Reply #2 on: June 05, 2007, 01:30:18 PM »
Sell it to me real cheap while you still can....

Most of us have had or will have the dreaded leak. Three places - 1 is the o-ring and gasket sealing between the head and cylinders (if only below the head) 2 is the head cover gasket - there is no pressure on these, but the gasket is not well fitting, and 3 is the rubber sealing between the cam towers and the cylinder head - 6 of them.

Bad news is the engine is a bear to remove without stripping the frame and "pouring the engine out of the frame with it's 1/4" clearance. It's murder on paint, so think about how you want tthe frame to look once you've re-installed.

Unless it's bad, there is no mechanical downside to it. You don't want to wear khakis for sure.

Regards,
Gordon

Kaws, Hondas, Yamahas, and Suzukis - especially Kaws

Offline OldSchool_IsCool

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Re: Oil on cooling fins, where's it coming from?
« Reply #3 on: June 05, 2007, 02:06:33 PM »
Get an aerosol can of foot powder.  Once your engine is clean and dry, spray some foot powder on the fins.  Go for a ride.  The oil will cake up in the foot powder showing you the source the leak.
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Offline nickjtc

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Re: Oil on cooling fins, where's it coming from?
« Reply #4 on: June 05, 2007, 03:56:38 PM »
Most of us have had or will have the dreaded leak. Three places - 1 is the o-ring and gasket sealing between the head and cylinders (if only below the head) 2 is the head cover gasket - there is no pressure on these, but the gasket is not well fitting, and 3 is the rubber sealing between the cam towers and the cylinder head - 6 of them.

It's almost certainly one of the above. Stick a discreet wad of kitchen paper towel in there and change it regularly.... like us humans these bikes tend to leak from various orifices when they get old.

"Death before Depends!!!" ::) ::)
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Offline medic09

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Re: Oil on cooling fins, where's it coming from?
« Reply #5 on: June 05, 2007, 04:47:33 PM »
Most of us have had or will have the dreaded leak. Three places - 1 is the o-ring and gasket sealing between the head and cylinders (if only below the head) 2 is the head cover gasket - there is no pressure on these, but the gasket is not well fitting, and 3 is the rubber sealing between the cam towers and the cylinder head - 6 of them.

It's almost certainly one of the above. Stick a discreet wad of kitchen paper towel in there and change it regularly.... like us humans these bikes tend to leak from various orifices when they get old.

"Death before Depends!!!" ::) ::)

 :D :D :D :D :D :D :D
Mordechai

'78 CB750K
'76 Triumph T160 Trident (rebuilding)
'07 aprilia Caponord

Santa Fe, NM

Offline mick750F

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Re: Oil on cooling fins, where's it coming from?
« Reply #6 on: June 05, 2007, 05:04:49 PM »

   Another possible culprit is the tach cable seal or even the tach cable itself if the sheathing has been compromised. I've had leaks in both and the oil was more apparent on the fins than on the valve cover.

Mike
'
Glosta, MA
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