i have an oil leak coming from somewhere behind the timing belt casing, but im not quite sure where its coming from. any idea of whats leaking and what could have caused it to leak?

If indeed it is one of the front engine seals the Volvo gods have smiled upon you.... it could have just as easily been the rear main seal and that is definitely a much bigger deal....

As everyone has advised clean up the ventilation plumbing and make sure you get all the places that could be constricted or plugged up as it only takes one to ruin your day.

Randy

The 240's have a crankcase ventilation system that can clog - especially if not tended to periodically - causing an increase in crankcase pressure with resulting leaks wherever it's most convenient for the oil.

The Flame Trap needs periodic cleaning. There's a breather box low down on the side of the block that also needs cleaning or replacing, but it's harder to get to.

Have a look in the 700/900 series FAQ. This is one of the many parts of that FAQ that applies to 240s.

http://www.brickboard.com/FAQ/700-900/EngineSealsBeltsVent.htm#Crankcase_Ventilation_A_Treatise
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Formerly Sophie's Maintainer. Sven: '89 245, IPD sways, E-fan conversion, 28+ mpg - auto tranny. 850 mi/week commute.

Probably the camshaft seal, and one cause is high crankcase pressure. When was the flametrap last cleaned? Check the hoses for blockage?

Could be any or all three shaft seals shown in the picture: Cam shaft, Intermediate shaft, Crank shaft. They are usually replaced as a group, about every 3rd timing belt or so (that's on the 50K belts, which yours is).


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Bruce Young
'93 940-NA (current) � 240s (one V8) � 140s � 122s � since '63.