ET: Engine (Twin) Persistent oil leak

A_HRD

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All good stuff, but Russ, if you have newly painted Shadow heads, check that they are still torqued-down to 32 ft-lbs before removing them. A friend had the same compression-leak problem after a few miles of use and when he came to remove the cylinder-head-brackets the head-nuts below were loose! The thick new paint had "given-way"!

Peter B
Bristol, UK.
 

greg brillus

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Yes I can confirm that point, I just recently stripped a Shadow engine that had been running ok, but the cylinder head nuts were literally finger tight. That is why I always re-torque the heads after the engine has been hot and carry out the next day when it is cold.
 

bmetcalf

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Do you loosen the nuts on top of the bracket and then use a crow's foot wrench on the head nuts or strip the bike down more than that?
 

greg brillus

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Not even that far, I back off the cylinder head bracket nuts. Then back off each one at a time and pull down in one go using a 13/16" ring and open end spanner. I use to use a spring scale, and given the spanner is around 9 to 10 inches long I pull down to 40 pounds on the scale. I don't even use the spring scale anymore, as i have a good feel for when it is tight........Using just one stock paper gasket under the barrels the nuts usually pull down less than one clock deviation, that is from 12:00 to 1;00 I tend to mark the nut and the head with a texter pen so I can see how much it moved. It is rare that they don't move.......Generally if stainless nuts on studs are used the nuts can grab a bit, so I use anti-seize or even grease on the threads before the nuts go on.
 

bmetcalf

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I've seen a chart on dry vs. lubed torques. I wonder about the practical effect on the low torque we need to use. But, you don't want galling.
 

litnman

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Robert, what is the swing on that lathe! Huge. What is the sledge hammer for??
 

Robert Watson

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The lathe swing is 18in dia in the gap which is partly home made, about 16in without, and a 48" bed. It was built about 1939 and spent its working life in a motor rewind shop starting at a Westinghouse facility near to a new mill in Nanaimo that was one for the first to not use line shafts but all individual motors drives on the equipment. I was wondering who would be the first to ask about the sledge hammer!
 

998cc

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All good stuff, but Russ, if you have newly painted Shadow heads, check that they are still torqued-down to 32 ft-lbs before removing them. A friend had the same compression-leak problem after a few miles of use and when he came to remove the cylinder-head-brackets the head-nuts below were loose! The thick new paint had "given-way"!

Peter B
Bristol, UK.
Good point Peter. I'll check them before pulling them.

Otherwise, the muffs and liners are new in this build. They seemed to lap in well, so the leak is perplexing. :confused:

Regards,
Russ
Northern California
 

vibrac

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I always go to about 28- 30 ft lbs and leave it overnight then goto 32 next day always clean paint from the under washer area and use the ended spring balance check after a first shake down with loosened bracket
This cylinder nut subject is the only time I use a torque wrench on a vincent
 
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