Oil under cover and in spark plug wells

astraoh · Post by **astraoh** » 08 Mar 2019, 20:33

Need your guidance. I changed spark plugs (SP) today and saw oil under SP cover and also in three SP wells. SP tips are dry, but shanks are full of oil. See attached photos. What do they tell you? 1997 Volvo XC70, ~ 165K miles, car runs OK. Thanks for your opinion.

Post by **erikv11** » 08 Mar 2019, 22:09

Leaky oil cap gasket and all the problematic oil is coming from the top. Check it, it should be pliable, likely it is hard as a rock.

Clean up the oil up top, clean the plugs and check gap (looks big), new cap gasket, should be good to go.

You can buy the cheap gaskets and change them often, or the pricey Volvo part and leave it in a long time https://www.fcpeuro.com/products/volvo- ... -1275379oe?. Budget works out the same.

Post by **abscate** » 09 Mar 2019, 02:55

Three sources of top end oil

1oil cap gasket as noted above. Made worse by bad PCV plugging, check with the “ glove test”

2 the PCV hose on top can be loose , that cheap hose clamp tend so cut the hose , especially if it’s aftermarket, in which case it’s probably soft and oily too.

3 orings between the cylinder head cover and cylinder head. That’s a big one too tackle. Timing belt and cover has to come off..

Get something up there and suck all that oil up and rinse without Simple green. Leave cover off and track new oil deposit to diagnose.

tardcart · Post by **tardcart** » 09 Mar 2019, 07:14

Yes, it looks like the block vent was serviced by the aftermarket clamp on the head hose. but you might have to go through it all. and check the small oriface PTC that goes into the intake tube where the vent terminates before the turbo for carbon clog. . but first replace the cap gasket and clean it up and leave it open to observe. If you use your wife's turkey baster rinse thoughly. Off subject; but Autolite plugs dont work as well as the Volvo plugs that are I think iridium and very small. those autolight are for American v8's and tractors. If your car is non turbo it may have a vacuum diaphragm on the breather box that goes bad, not sure what year they started that.. check vacuum line at tree and on the end of the manifold by altenator if turbo. If you do take the intake off which is no fun, use only volvo parts and dont make up your own lines unless you are only going to run the car for another year. lots of info on all this if you look back.

Post by **erikv11** » 09 Mar 2019, 10:28

OP's car is a turbo, look at the engine pic.

Autolite 3923 is not my first choice but it is totally fine for a P80 turbo engine, liker many other brands of copper core plugs. This has been proven by many millions of documented miles on forum pages. Gap them to to 0.028.

The Autolites won't last nearly as long as the Volvo plug but they are also only $1 each.

But those aftermarket spark plug wires, I'd get rid of those ...