Oil Leaking Into Spark Plug Chamber Topic is solved

MathalomuleM31 · Post by **MathalomuleM31** » 10 Mar 2017, 10:14

Hello Guys! hope you are doing well.

I have a 1999 Volvo S70 Non-Turbo 170,000 miles, and recently I've had some rough idling and starting trouble on and off for the past 6-8 months (I don't drive that often, maybe 2 or 3 times a week) so I decided to change my spark plugs and that's when I discovered my second cylinder spark plug chamber was half filled with oil!

I was able to see clearly it was coming from one of the bolts right next to the boot (See pick, the one I'm pointing to).

: Leaky Bolt

So no wonder it was having a hard time starting. But with new plugs and the oil cleared we are running great.

The bolt that the oil was leaking from didn't appear to be loose, I was able to tighten it maybe 1/8 of a turn. But my concern is that in a few weeks or months its going to continue leaking and fill the spark plug chamber up with oil again. There was also a little oil throughout the area where the other spark plugs are (as you can see in the pic) but no other apparent leak sources. It did look like some oil was spilt from the oil fill cap area through out the years of oil changes.

What do you guys recommend for tightening up the leaky bolt that's putting oil into the spark plug chamber? And just overall keeping oil out of this area?

Thank you for your help!

Post by **misha** » 10 Mar 2017, 10:20

I would say that the seal on oil cap is bad...pretty common....i doubt that oil escaped through that bolt.

MathalomuleM31 · Post by **MathalomuleM31** » 10 Mar 2017, 15:47

misha wrote:I would say that the seal on oil cap is bad...pretty common....i doubt that oil escaped through that bolt.

Hmm... what has me scratching my head though is that the oil was only in that one spark plug cylinder. The other ones were fine. #5 had a tiny bit but it seemed old like it had been there for a while around the rim near the plug.

But yeah I think ill go ahead and get a new seal for the oil cap.

clifford06 · Post by **clifford06** » 10 Mar 2017, 19:10

Greetings. It is possible for oil to leak from these bolts. I had a leak that was caused by one. Clean the oil off and tighten bolt. Leave the sparkplug cover off for a few days . Be sure to keep TB section of cover on. A little gasket glue on the bolt won't hurt.

clifford06 · Post by **clifford06** » 10 Mar 2017, 19:20

Be sure to shop vac all of the bits of plastic wire loom up and replace with new, so they don't get in your sparkplug holes.

Post by **cn90** » 10 Mar 2017, 22:08

I removed the cosmetic cover and stored in my garage shelf.
I will NEVER re-install the cosmetic cover b/c:
1. I now have quick access to the spark plug area.
2. Any spilled oil or broken CCV hose is discovered promptly and wiped clean.
3. When washing engine, if you are not careful, water will get under the cover ---> spark plug hole ---> misfire. Don't ask how I know LOL...

This topic (whether to remove the cosmetic cover) has been beaten to death in forum but I am glad I did.
To me, the cosmetic cover is worthless piece of plastic.

Post by **scot850** » 11 Mar 2017, 09:32

Replace the oil filler seal. When they leak (usually ever 2-3 years) they always soak #2 cylinder first and then #3.

Neil.

Post by **MadeInJapan** » 11 Mar 2017, 09:48

Yes- the rubber ring that goes on the oil filler cap- I change these out routinely once a year no matter what. They go bad! So I have a bag full of them. They fit all of our Volvos except the S40. That said, be very very careful of tightening down the cam cover bolts. These are torqued very lightly and any pressure beyond what they are supposed to be will strip them and then you're in for some trouble. The mechanic (if you can call him that) screwed up 4 of these on my S70 head and acted like nothing was wrong when he gave the car back to me. I discovered major oil leaking out of two of these that were in the corners of the cam cover. Long story- to fix everything, I ended up getting my old head back, machining surfaces and doing an entire upper head job over again. It was that critical and only discovered his sloppy work after loose bolts were discovered. They were loose because the guy had over-tightened them and stripped them.

Post by **abscate** » 11 Mar 2017, 10:13

17 Nm torque for those cam cover screws. With a 6 inch 1/4 drive wrench, you can exceed this torque really easily with just your hand pressure.

Post by **MadeInJapan** » 11 Mar 2017, 11:38

This thread reminded me to buy some oil filler cap seals. I usually have a ton of them but when I looked I couldn't find any. FCP is getting beat on price by Eeuroparts right now for these and for oil drain plug aluminum gaskets. Don't know why. I needed another part too (door hinge for my wife's V70- I had cheaped out for a ERO branded one that didn't hold up so I got a Volvo one this time)...long story short, I got price matching working in my favor over on Eeuro this time. It's a crap shoot. FCP will price match too.

Anyway- sorry for the rambling. I was looking for a gasket under the oil filler cap that won't harden and crack like the ones we've been using and IPD makes one that's Vitron- I believe that's silicone? They claim it doesn't do the cracking and breaking but then again they want $10 for just one. I passed on that and bought 10 of these for $4.90... (49 cents each)... I'll just continue replacing annually! But, this makes me think.... why doesn't anyone make these for cheaper out of silicone? Seems I could get a sheet of silicone at the right thickness and just stamp out a bunch of these- would be very easy to do (at a fraction of the cost)...hmmmm- might have to look into that.