850 frame trap and oil leak

Our 850 has about 87K miles now. From 60+ miles, a rear oil leak was
developed and I learned there is a frame trap which was clogged really bad,
I cleaned it by carb sprayer really well and replaced with a new O ring.
Since then, I have cleaned the frame trap regularly, or about 6,000 miles
interval. The engine runs smooth after each frame trap cleaning. However,
I realized the oil clogged up real fast. How? Is the piston rings getting
bad or a sign of something else getting aged? The coolant/antifreeze was
regularly changed, and the engine temperature has been fine.

Is there different motor oil that would cause less oil fume and thus less
frame trap oil clogged up?

I use 5W30 for winter, 10W30 or 10W40 for the rest of climate.

thanks and best regards,

Joe
96 850 87K
85 740

 

Synthetic oil won't cause less fumes, but will cause less deposit
buildup. Cleaning out the throttle body may help. However, on the 850
the oil trap clogs up, and because of its nature it almost impossible to
clean. Also the intake manifold needs to be removed to change it, it's
a fairly long job.

--
Mike F.
Thornhill (near Toronto), Ont.

NOTE: new address!!
Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)

 

Curious,
cleaning up the flame trap cleared up the leak?

I replaced my rear seal in S70, on the theory that once this seal was
breached, oil would keep leaking through - very costly repair

 

We have owned quite a few Volvos, and always have had them serviced at a
local independent shop. The owner of the shop hires Volvo-trained
mechanics. They have told us consistently to stay away from 10w-40 oil
in all of our Volvos, from our 240 days to our V70. Mayhap there is a
problem with one of the additives that make up the 10w-40?

 

Yes, the flame trap being clogged can most definately cause oil leaks. It
makes pressure build up much higher than normal casuing leakage at the fill
cap and other places. Left unchecked (or undetected) it can cause excess
pressure on the rear main seal cuasing premature failure and necessitating
replacement of it. (I went through this whole scenario over the course of 10
months on my 94 940. Of couse, the 920 only cost about $225 to replace the
rear main.. not so nice on my wifes 95 850 when it was her turn for the
same. I've hear it's very common for most Volvos to need a rear main at
between 110-150K.