1998 S90 Oil drip from rear of the engine

ultravires1313 · Post by **ultravires1313** » 01 Mar 2014, 23:04

My S90 developed a leak during a cold snap here in Chicago a couple of weeks ago. I was running fine one night and when I started it the next morning I noticed the sound then when I went around a sweeping turn the oil light came on. I initially thought it was just normal( I've) had it for four months then I noticed the smell of burning oil, checked the fluid levels and saw it was 1 qt low. I noticed there was oil leaking onto the transmission bell housing on the passenger side from the back of the engine block.. Its a noticeable drip when the car is running. I purchased Timken cam seals but I can find no reference as to how to replace them, if in fact they are the problem. Any assistance would be appreciated.

danr960 · Post by **danr960** » 03 Mar 2014, 11:18

There may be two seals one for each cam shaft, but sometimes there is not one for the intake cam. The cover is sealed with RTV and popped into position. Most likely your exhaust cam seal is leaking, you should try to verify this though.

As you may have already seen, not much room to work back there. Those large torx bolts that hold the cam sensor on can be troublesome to back out. Make sure you use a quality tool, not one from a cheap kit from HD or Menards, but one from a quality tool company, I think it is a 40. You get one chance to back them out, they are fairly soft and will round out it the tool does not fit snuggly. Once the sensor is removed, get a mirror to view the sensor shutter wheel, I believe it is a 10mm bolt, the shutter wheel had a notch that fits the cam only one way, so you don't have to worry about it's orientation. Removing the old seal will be a pain, it will be as hard as plastic from heat and age, but it comes out like any other shaft seal, don't be timid. Before I removed mine, I confirmed that it was indeed leaking, with the sensor disconnected, the engine idling, use the mirror and a light to watch for oil weeping and collecting at the bottom of the bore. Don't get a rag in there, don't want any snags. You will need something to push the new seal in, I have an set of old bearing races that are just the perfect size, but have heard of people using the right diameter sized PVC pipe. Just use care in the cutting of the pipe and get the edges a smooth sanding. The factory tool is metal and uses the bolt hole on the cam to drive the installer in to the correct depth. It is not hard, but once you commit you have to follow through. If the seal is not installed perpendicular to the cam shaft, it will leak again.

The oil level concerns me, because the cam seals don't usually leak all that much oil when running. So if you made a turn into a corner which caused your oil light to trigger, that sounds weird, especially if it was only down a quart. My son has had our '94 down 3+ quarts and no signal from the oil light.

DanR '94 964 390,000 miles (156,000 on the new engine)

Post by **billofdurham** » 04 Mar 2014, 11:44

Where exactly is the oil coming from? On my 960 I had a similar problem but before I started throwing money at it I did a very thorough examination and found that the head gasket was leaking oil out of the engine. No trace of oil in the coolant. The oil only came out on hard acceleration, especially going uphill with a caravan tied to the back. My local Volvo dealer's top mechanic said it was not a rare occurrence.

Head off, resurfaced, new gasket and back together - no more oil leak.

Bill.

ultravires1313 · Post by **ultravires1313** » 08 Mar 2014, 14:40

I noticed the oil on the first hose from the right (there are two) I looked at the cam seal that has the torx screw on it and felt around it and it was dry. Then I started the car and the drip began again on the two protruding pieces of metal that I'm thinking is the block but it may be the cylinder head. I've never owned a front wheel drive car but I'm betting this is one of the few occasions it'd be easier to fix!

lummert · Post by **lummert** » 08 Mar 2014, 16:46

S90 is not a FWD car. It's rear wheel drive.

Post by **precopster** » 09 Mar 2014, 04:13

lummert wrote:S90 is not a FWD car. It's rear wheel drive.

The S90 was the BEST RWD car that Volvo ever produced in my opinion. In fact I'd rather have an S90 over a FWD P80 car after having owned a 960, an 850 and 3 other P80 cars......

I didn't like it at all when I had to repair the rear cam seal leak on my 960 (same engine as S90)

ultravires1313 · Post by **ultravires1313** » 09 Mar 2014, 10:23

I know it isn't a front wheel drive car, I said if it were a front wheel drive car it would be easier. Could someone familiar with the site layout pm me a diagram of the rear of the engine. Thanks. Never owned fwd never will. I bought the s90 because its rwd and NOT the size of a whale, the perfect size.

Post by **mikealder** » 09 Mar 2014, 11:18

Is the car N/A or a Turbo?

Not sure on the 6 pot engine but the 5 pot N/A engine has a blanking cap fitted to where the turbo oil return pipe would go in the rear of the block, when this lets go the oil sprays out above around 2500 RPM - Just repaired mine on the V70 yesterday - Mike

Post by **precopster** » 09 Mar 2014, 11:31

S90s are non turbo. They have the blanking cap on the inlet side.

Blanking caps are usually very reliable because they can be sealed in with sealant and no moving parts.....cam seals not so......in fact on my '99 V70 I recall no cam seal was fitted to the cap side (exhaust) at all.

A photo of the rear of the engine is a tall order as getting a camera in there is tough work.

It's actually identical to the non turbo 5 of which there are plenty of photos on this site, the best I've seen are on Tracy's true soaps Volvo 850 head replacement tutorial. Search google for speed. Page 5 pic 8 then page 6 pic 2.

The cam sensor must be removed via 2 X torx 40s then levered out. After this the 10mm bolt holding the sensor ring is removed. Then you reach in and grab the ring. Then it's mirror and pick time !!

Ethan Rode · Post by **Ethan Rode** » 15 Mar 2014, 01:55

There's no seal on the intake side, just a large plug. If it is coming from the cam seal, your cam position sensor will be full of oil. It's not terribly difficult to get off, so I'd start there.

Oil seepage like this may be the result of a blocked oil trap, or blocked flame trap.

A handy trick for replacing the cam seals is to use a 12 point 29mm socket and longer 7mm bolt. put the socket on the end of the cam, thread the bolt into the cam, and use the socket as a press.