Vented oil cap to intake box mod?

Post by **SonicAdventure** » 16 Jan 2017, 12:34

Hey everyone, I'm trying to get the resources together to do my PCV job, but unfortunately I probably won't have the money to do something like this till late February. In the mean time I want to do everything I can to keep the car running ok and keep the crankcase pressure down.

I saw a post on another forum some time ago that involved getting an extra oil cap from the junkyard and drilling a hole in the top of it all the way through the metal bottom. Then, a length of copper rod with a 90 degree elbow is inserted into the hole and JB Welded into place. The rod length is supposed to be whatever the height of the oil cap is from the bottom of the metal surface to the top of the cap, with about 1/8" inch of space between the copper elbow and the cap so that a piece of 5/8" inner diameter heater hose can be installed and clamped in place on the elbow. Then the heater hose is routed to either the intake port on the air box where the large hose from the PCV box would go (not sure what you are suppose to do with that) or it's to be spliced into the intake hose to the PCV box OR it is to be routed to a modded intake port in the air box with a similar copper pipe / elbow combination...I can't remember and I can't remember where I saw this being discussed.

I had that dipstick snorkel in place for a little while but it was allowing condensation to develop in the snorkel and in the dipstick tube...after I cleaned it out I didn't have any problems with condensation until just recently, but I realize that is due to driving short trips and it being colder outside.

I hate not being able to afford to just have this darn PCV job done by a pro, but it's just not in the cards. Even buying the parts is a stretch, plus the downtime of maybe not having a car until it's all sorted out.

If anyone can chime in on the vented oil cap mod or knows where I might have read it, please let me know. Also any other suggestions of what to do to keep the pressure down until I can get this fixed the right way. Thanks.

Post by **abscate** » 16 Jan 2017, 13:07

Poor mans fix = pull the dipstick and vent the tube down the road with about $4 of PVC

Post by **cn90** » 16 Jan 2017, 13:21

Actually, you can do the PCV for about $30 or so. All you need are:
- Hose from oil trap to valve cover...$22 or so. Use only Volvo OEM.
- Short hoses from oil trap ---> engine x2.

- Re-use the oil trap, clean it an re-use it.
- 5/8-inch hose mod. I didn't use the 90-degree copper elbow and 5 years later I am fine, as long as you don't introduce any kink in the hose, you are OK. Copper elbow is cheap, about $1-$2 at hardware store.
- Clamps: just get the correct sizes.

beigg · Post by **beigg** » 16 Jan 2017, 13:54

I would be inclined to route the "new" cap port to the PCV with oil heater element port that is at the turbocharger air inlet. It might require a "T" if plugging the oem line and putting the "new" cap port line to it doesn't net desired results.

Post by **polskamafia mjl** » 16 Jan 2017, 17:36

Leave your dipstick snorkel in place. It wasn't allowing condensation in anymore than the actual dipstick would. Like you mentioned those short trips are what's causing it.

As cn90 mentioned though the parts for the PCV job aren't very expensive if you avoid buy the kit. You're only issue then becomes how long it takes you to do the job. It should only take a few hours.

Post by **SonicAdventure** » 16 Jan 2017, 20:05

beigg wrote:I would be inclined to route the "new" cap port to the PCV with oil heater element port that is at the turbocharger air inlet. It might require a "T" if plugging the oem line and putting the "new" cap port line to it doesn't net desired results.

My car is non-turbo. I was thinking of running the tube from the oil cap to the intake nearby the PTC valve, or possibly in the side of the air intake box.

Post by **erikv11** » 16 Jan 2017, 22:40

SonicAdventure wrote:
beigg wrote:I would be inclined to route the "new" cap port to the PCV with oil heater element port that is at the turbocharger air inlet. It might require a "T" if plugging the oem line and putting the "new" cap port line to it doesn't net desired results.
My car is non-turbo. I was thinking of running the tube from the oil cap to the intake nearby the PTC valve, or possibly in the side of the air intake box.

I'm not following the line here. There is no PTC on an NA engine. You mean at the flame trap housing, maybe?

Post by **SonicAdventure** » 16 Jan 2017, 23:40

erikv11 wrote:
SonicAdventure wrote:
beigg wrote:I would be inclined to route the "new" cap port to the PCV with oil heater element port that is at the turbocharger air inlet. It might require a "T" if plugging the oem line and putting the "new" cap port line to it doesn't net desired results.
My car is non-turbo. I was thinking of running the tube from the oil cap to the intake nearby the PTC valve, or possibly in the side of the air intake box.
I'm not following the line here. There is no PTC on an NA engine. You mean at the flame trap housing, maybe?

Yes you are correct. I suppose I would put it somewhere on the back side of the air intake box above the air filter, sort of pointing back toward the heater core hoses. That way the modded heater hose could be routed close to (and possibly zip-tied to) the upper engine mount bracket.

beigg · Post by **beigg** » 17 Jan 2017, 01:11

you got it!

Post by **rspi** » 17 Jan 2017, 03:33

You will also need an intake manifold gasket.