Supplemental PCV system?

Post by **t5rrr** » 28 Dec 2009, 11:16

I just got my 855 with 155k a month ago and checked the PCV system, result was some white smoke puffing out of the dipstick tube when the engine is fully warmed.

I won't be able to do the complete PCV replacement for another 3-6 months. In the meantime I was thinking of temporarily relieving the crankcase pressure by connecting a hose from the dipstick tube into a rattle type PCV valve (pic below) then back into the intake trac.

Does this sound even feasible?

KRUZNBY · Post by **KRUZNBY** » 28 Dec 2009, 13:20

I'm interested in this as well. I've done the PCV repair and I still have pressure.

Post by **jblackburn** » 28 Dec 2009, 14:06

I got about halfway through the PCV repair today, in between answering 12000 phone calls for work because no one knows what's going on, and had to stop because I couldn't feel my hands anymore. I'd be interested if this works for you - the concept itself makes sense to me. I spent about an hour and a half today trying to get the PTC nipple out of the back of the car by the turbo to clean it out. If you can't do the rest of the PCV system for some time, you could try cleaning that itself - it seems to have relieved SOME of my pressure for now.

I think if I get through this whole procedure tomorrow and still have pressure in the system, I'm just going to take a huge sledgehammer to the whole engine.

Post by **renns** » 28 Dec 2009, 14:32

I'd expect you could try rigging up a temporary PCV system as you show, but here's a couple other related thoughts:

I've built crankcase ventilation systems for off-road vehicles in the past. Here's what worked well for us: Shove the crankcase vent hose down into the open top of a catch bottle 1/2 litre or so in size, and then fill the remaining space in the bottle with stainless steel wool. The wool will collect the moisture/oil, and keep it in the bottle, while allowing the combustion gases to escape back out the top. Check the bottle periodically, and drain out any collected liquids.

A few weeks back I did the sump o-ring repair. While finishing up that job, I cleaned out the flame trap, and succeeded in breaking the brittle plastic tube that runs from the PCV tank to the flame trap. I drove the car more than 3 weeks in that condition, until I had a chance to repair. There was a slight hot oil smell inside the car occasionally, but other than that, no issue. Some smoke/steam is visible exiting that broken tube when the engine is warm. I was expecting to see some oil residue buildup on the top of the engine by the end of the broken tubing, but there was little if any new oil in the area.

Jim W · Post by **Jim W** » 28 Dec 2009, 14:37

I just finished doing the PCV job on a 97 850GLT. Dipstick tube still smoking and cleaned out the PTC thingy on the airintake 3 times already. The routing on the oil trap is different from the diagram on Grotons website where I bought the parts and hooked it up the way it was on the car. Maybe going your route if cannot find the problem. Anyone have a answer?

Post by **renns** » 28 Dec 2009, 14:48

Jim W wrote:I just finished doing the PCV job on a 97 850GLT. Dipstick tube still smoking and cleaned out the PTC thingy on the airintake 3 times already. The routing on the oil trap is different from the diagram on Grotons website where I bought the parts and hooked it up the way it was on the car. Maybe going your route if cannot find the problem. Anyone have a answer?

Jim,

Somewhere on this forum there's a discussion about some docs showing incorrect PCV hose routing. I think MadeInJapan figured it out? A search should find those references if someone else doesn't post it up for you.

Post by **t5rrr** » 28 Dec 2009, 14:53

I have a NA motor and the flame trap was already missing when I bought the car. The flame trap elbow had some crud which I cleaned off. I did however broke the little vacuum nipple at the flame trap elbow and it's now plugged with a screw

Renns:
I think I broke the same tubing you are talking about

I installed a silicone hose as a temp coupler

I'll be trying this supplemental PCV setup without a catch can first, if there is significant oil reside in the hose/PCV valve then I'll add an inline catch can as a second part of this experiment.

Post by **renns** » 28 Dec 2009, 18:23

t5rrr wrote:Renns:
I think I broke the same tubing you are talking about

Yep, that's the one, only mine broke closer to the flame trap end. I ended up splicing mine today with some 1/2" ID vinyl tubing.

ignatz · Post by **ignatz** » 29 Dec 2009, 03:54

In the "old" days when I had cars with too much blowby, I also ran a catch can. The can was used more for a liquid trap because I would run the final can breather under the car so the ventelation system would'nt suck the fumes into the car. I had an Escort that the breather vent ended in the right front wheel well. On a cold day at a stop light, smoke would come out of the wheel well! My old 122 Volvo had a similar setup.
Be warned, depending how you route make shift breather lines, you can create a "trap". This time of year these traps can freeze and block your make shift breather.

Post by **t5rrr** » 07 Jan 2010, 18:12

Ok, I rigged something up with a bunch of silicone hoses I have laying around and a smuckers peanut butter glass jar with steel wool in it

This has been on for about a week and there is obvious signs of condensation at the dipstick area (creamy fluid) and moisture trapped in the jar. The steel wool has begun rusting.

Best part is, no more oil shooting out the filler cap! Now for a new gasket

Hope that alleviates the crankcase pressures until I get the PCV system overhauled in the Spring.