2.5 4 banger...Ring "Blow-by" or WHAT (???)

I have a 1993 Plymouth Sundance with a 2.5 4cyl. 200,000 miles.

It blew a head gasket recently and I replaced it. Hmmmm...I checked the head deck for warpage and it appeared to be good so I reassembled with new timing belt and water pump. I flushed cooling and engine oil systems and reinstalled a quality oil, filter and coolant.

Everything is fine for a few days then the wife tells me her oil light is coming on. I check the oil and it is way down with evidence of a major leak at the Front main crank seal. So...I pull it down to the timing cover and when a removed the timing belt cog from the crank I see the main seal blown out of its seat in the timing cover! Well...I dont know what to think about that. I look at the old seal and it looks pretty rough. Dryed and cracked around the internal rubber. With 200K on it...its time for a new one.

Ok...considering the mileage on the car, I go down and buy a new crack main seal and repair sleeve and install both. They seem to go on ok and the seal seats into position just like it should.

I reassemble everything and it does fine...for a few days....then The same old story...oil light came on...2 quarts in 30 miles...oil blown all over the lower engine and right side of the car...

...THIS time, I put some oil in...start the engine and feel for pressure or vacuum at the oil filler. Its BLOWING air, BIG time!

Could it be ring blow-by pressurizing the crank case enough to literally blow the oil seal out of its seat??? Hard to believe, I know...but possible???

I didnt pull or replace the timing cover, in which the seal seats into last time. I'm fixing to tear into it again this weekend, but before I do I want to buy a compression tester and check compression and leak down on the cylinders.

Anybody have any other ideas, recommendations or suggestions on what might be going on and the best way to fix it.? Yeah...the car is high miles...but other than this, and the head gasket, it has been running fine.

Could the blown head gasket to start with be a clue that I'm not catching???

Thanks in advance for any info you may care to share,

Dave...in (Sunny, Hot, sticky and humid) Florida

Reply to
D. Reid
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Probably getting to be a tired pony by now.

Mmm. Excessive crankcase pressure.

How long since the *COMPLETE* crankcase ventillation system -- not just the PCV valve -- had a thorough going-through? You have 200k miles, it's definitely time to go to the larger-bore PCV valve.

Yep, it surely could be.

For your reference, my detailed description of your car's crankcase ventillation system and the larger-bore PCV valve is here:

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-Stern

Reply to
Daniel J. Stern

Sounds like ring blow by to me. I once had a Chevy Vega (2.3L aluminum block) that blew enough oil in 30 miles (my 1-way commute) driving to fill up a 1 quart container. I actually designed/implemented a simple "recovery tank" that had a rubber hose from the oil dipstick to the open air tank. After about this distance of driving, I used to re-claim the oil by pouring it back into the oil fill hole and then putting the empty reservoir back in place.

I did this and supplemented with fresh oil as needed till I could afford a remanufactured short block with steel sleeves! (I was in college and this was my daily driver at that time.)

Bob

Reply to
Bob Shuman

Dan, I would like to put the larger bore PVC in my 2.5L Spirit. If I buy the NAPA PVC for a 3.3L V6, would that do, or should I stay with the OEM P/N that you mention?

Also, is there an aftermarket source for the "elbow" tube that connects the PVC to the valve cover housing? Mine is cracked now needs replacement.

Thanks,

Kirk Matheson

Reply to
Kirk Matheson

NAPA's OK as long as you get the first-line Echlin, not the "Mileage Plus" crapola from China. The one you need is a 2-9207.

No. Both the elbow pipe at the center-rear of the camshaft cover and the formed "almost straight but not quite" one that connects the right-rear corner of the cam cover to the front face of the air cleaner housing are dealer-only items. You could probably kludge something up, but don't.

-Stern

Reply to
Daniel J. Stern

I replaced those parts (PCV valve and rubber 90). The valve was not the big bore type however. The rubber 90's and some other tubing, I aquired at a "U-Pull" it yard in this area. You might have to look under a few hoods before you find a servicable replacement...but it should be cheap...and if you're buying other parts they will usually give you stuff like this.

I'm going back into this engine this weekend to replace front main seal. I'am going to see if there is a way to rig a "keeper" device of somesort to keep the seal in place. Then figure away to release or reduce crankcase pressure.

Reply to
D. Reid

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