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Belsy
01-10-2011, 09:37 AM
Having read several posts on this I have a question: on my stock 95 w/dunn heads I have a small puddle accumulating in the front of the pass. side inj. hsg. and would like a consensus on stopping it.
Theory of pulling all PCV flow thru OIL CATCH can seems to at least leave most of the oil blow by in the can rather than back thru inj.hsg.!!

Key ?? being: does the large buildup of oil resting in the inj. hsg. come before the pcv function or after the system has dumped it back thru the intake process in to the hsgs.??

I have recently pulled plenum for other problems and all is well except this so I would like to attack this externally if poss.

Please fire any opinions my way,

zr1don
01-10-2011, 02:41 PM
If the oil puddle is on the exterior surface of the block, it is most likely from one of the oil pressure senders or the oil cooler lines.

Belsy
01-10-2011, 06:12 PM
The puddle is on top of the head at the front of the inj. hsg. I can see the trail from the mating of the hsg to the head. I'd rather not pull plenum to re-gasket at this time and also feel any reduction of oil in the hsg. is a good thing!!

So back to my question of the pcv cycle.

A26B
01-10-2011, 07:11 PM
Key ?? being: does the large buildup of oil resting in the inj. hsg. come before the pcv function or after the system has dumped it back thru the intake process in to the hsgs.??

The oil laden vapor from the crankcase flows first from
(1) the cylinder heads and the crankcase ventilation box under the plenum, into the injector housings,
(2) then from the injector housings through the grommets & pipes on outside of each inj hsng, to the PCV valve lower hose at the rear of the engine, then
(3) up through the PCV's,
(4) then through the 1/4" line on the LH side of the plenum, then
(5) back into the plenum
(6) and finally back into the combustion process through the intake runner.

So, the oil inside the injector housings occurs first, before the PCV's.

Once it's in the plenum, it goes only to combustion as a direct shot through the inj hsngs to the cylinder heads & valves.

Belsy
01-10-2011, 07:44 PM
Jerry,

Thanks for the reply!! Based on that would a stronger more efficient breather / pcv design be worth a try dumping into a can any drippage & vapor before going thru plenum?
The obvious repair being tear down & re-gasket is not exciting but experimenting with this constant complaint could be. Any thoughts??

A26B
01-10-2011, 10:21 PM
Gene,

Would it be possible to get a good photo of the oil puddling "accumulating in the front of the pass. side inj. hsg."?

I'm not yet convinced the PCV system has anything to do with your oil puddle.

Pete
01-11-2011, 12:14 PM
Most common problem between the IH and head is the IH gasket is leaking the 3 ventilation hole (actually 2) if you installed new gasket maybe swas not cleaned good or some crud was there.

Always clean those surfaces very good, i use some silicone on those 3 oil holes or use the black form-a-gasket sealer i don't know what it's called.

Pete

Belsy
01-11-2011, 01:12 PM
Here are 2 pics of area please note dark area at base of inj. hsg.(pic 1)
I have wiped the puddle and added a temp pad to absorb future (pic 2).

There is a distinctive oil mark at base of gasket to head area. PCV may not be the main cause but may be improved to eliminate so much oil remaining in the hsg.??? Time to experiment??

Thanks for your time & thoughts,

A26B
01-11-2011, 02:30 PM
OK, I was taking your comment "small puddle accumulating in the front of the pass. side inj. hsg." literally in front of the injector housing, whareas it is on the side of the injector housing, towards the front.
Oil leaks at the location shown in the photos is typical & often associated with loose injector housing bolts.

1. thoroughly clean & degrease gasket surface,
2. clean & degrease all inj hsng bolts,
3. install new gaskets, no sealant required on Jerrys Gaskets, others may benefit.
4. apply loctite 242, med strength (blue)
5. tighten/torque bolts as per serv manual pattern

Installing an oil catch can in the PCV return loop will do nothing to fix the leak you are concerned with. The catch can will only collect some of the oil that would otherwise go back to the plenum.