1997 Volvo 850 R smoke/steam out of oil filler cap?

hours · Post by **hours** » 11 Dec 2014, 00:13

I have a '97 volvo 850 R with 185,000 miles. ive owned it for 2 months and synthetic oil is used in it but i havent changed the oil yet. when i opened the oil filler cap today just after i drove it, smoke or steam came out of it. i checked the dipstick and there was white sort of gunky stuff on it. what is that? would an oil change fix that?

Post by **cn90** » 11 Dec 2014, 06:20

Change oil and filter using Mann or Mahle.
Then lift the dipstick upward about 2 or 3mm while you do some reading on PCV overhaul. I wrote a mod using 5/8 inch heater hose.

Post by **tryingbe** » 11 Dec 2014, 06:36

cn90 wrote: I wrote a mod using 5/8 inch heater hose.

Heater core hose can't withstand oil for long. Use hoses rated for oil only.

Post by **oragex** » 11 Dec 2014, 06:56

there's a pcv test shown on Youtube

is there also steam forcing out of the dipstick tube?

Post by **E Showell** » 11 Dec 2014, 07:14

Let's calm down a bit guys -- you mean you've never seen vapor escaping from the oil filler cap on opening a hot engine? I'd consider that perfectly normal. Before we send "hours" racing to do a PCV service don't you think he might try the balloon on the dipstick tube test to see if there is positive crankcase pressure?

Hours -- remove dipstick, place balloon over dipstick tube. Start engine and allow to idle. Balloon should not inflate. If it does, you most likely have a clogged PCV (Positive Crankcase Ventilation) system that will require servicing. Another test for this, again, with dipstick removed, is to see if you get smoke rising from the dipstick tube. If so, you have positive crankcase pressure -- not good. That has been known to blow out cam seals, rear main seals, etc. if neglected too long.

If you have positive crankcase pressure and need to drive the car for a bit until you can service the PCV system, then leave the dipstick loose -- don't seat it all the way -- and drive like that. The unsealed dipstick tube will allow some crankcase pressure to vent, but service the PCV asap. There is a detailed, extensive write up on here for performing that service. It isn't an easy job -- mostly time consuming -- but it can be done on a DIY basis if you're a confident amateur wrench and can follow simple directions (available from this site). Allow six hours for the job if it is your first time, although you might do it in less time than that.

I'm guessing it is a $600 job parts and labor if you have a local independent Volvo specialist do it (but I don't know how many independent Volvo specialists there are in China, or what mechanic's hourly labor rates might be).

Post by **rspi** » 12 Dec 2014, 06:30

Redneck · Post by **Redneck** » 12 Dec 2014, 13:12

Volvo is now owned by a Chinese car company. Since most parts are made in China, it may be a very good place to own Volvo and get parts for a ridiculously cheap price. Mechanic's work must be really cheap too.

@hours, can you tell us where we can buy some good Volvo parts online for a great price directly from China?

You need to do your PCV, but use the correct Volvo OEM hoses.

Post by **precopster** » 12 Dec 2014, 22:59

I just replaced the PCV on a '99 V70 NA yesterday with 274K kilometres on original PCV that had considerable positive pressure; so much pressure that it was leaking engine oil all over the top of the engine even with a new cap seal!!

I purchased the IPD kit which contains all items needed including intake gasket, dipstick o ring and injector o rings. The PCV parts were genuine Volvo and the intake gasket was aftermarket. They threw in a set of quality screw clamps as well.

I was really careful about cleaning out the ports with doubled up thin wire and compressed air.

The repair went so well that when I pulled the dipstick I heard a huge rush of air and I thought it was heading out of the engine. Upon doing the rubber glove test there was so much vacuum it could have suck started a Harley!! Great result