Hot Rod Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
415 Posts
Discussion Starter #1
Ok, here's the situation. When accelerating hard my engine seems to use a bit of oil. Its broken in, I'm running 15w40 Mobile oil. I think I've traced the consumption to the pcv valve. Its always has oil in it. To verify this I installed a clear plastic hose from the pcv valve to the carb and the line has traces of oil in it. Not a lot but more of a film of oil. I removed the valve cover, blocked off the bottom of the valve cover baffle for the pcv with sheet steel and drilled a 1/4 in hole in the side of the baffle so it can breath. Took the car out for a hard run and still oil in the hose. The hose actually collapsed so I replaced it with the hard rubber line. I have a K&N breather on the oppisite valve cover. There is vacuun in the engine. I verified this by holding a paper towel over the breather hole and it sucked in. Any ideas as to why this is happening? To my knowledge the should be no oil in the pcv valve. The engine is a 406 sbc with Sportsman ll heads, rpm intake roller rockers ect. Its built and puts out a lot of power. Idle vacuum is 14 inches if that matters.

Thanks
Steve
 

·
Super Moderator
Joined
·
6,623 Posts
Does the oil consumption disappear when you disconnect the PCV?

Sounds like the oil consumption and the PCV may be unrelated, an oil film in the hose is acceptable. Your baffle was the right idea to prevent oil splash from finding it's way into the PCV system.
 

·
Registered
Joined
·
164 Posts
I had and mostlikely still have a severe oil consumption problem with my 383 stroker...For long I have pointed the PCV as faulty as I have aftermarket valve covers that didn't have much of a baffle into them. I had installed a OEM GM oil baffle inside the cover that had the PCV running to and with much desesperation found out that didn't cure any of the problem....the rate was about 1 quart to 250 miles or so!

From advices received on this forum I made a test wich was to decellerate (on compression)from ,lets say 60 mph, to 15-20 miles per hour then pressed hard on the accellerator...boy did ever a smoking cloud came out the exhaust then.....till then I never had such smoke from the exhaust under any situations!

So I had my heads checked and the exhaust guides and seals were gone and got replaced...I never ran the engine after this ,another problem having devellopped, but sure hope this was the faulty guy!

My engine is out the car now and will be at the shop soon and totally stripped down...I'll know more about this later but keep looking for other source than the pcv...blueish smokey at start-ups is a sign of worned seals that could also let oil passing towards the combustion chambers.

Ronald.
 

·
Registered
Joined
·
415 Posts
Discussion Starter #4
4 Jaw Chuck: Does the oil consumption disappear when you disconnect the PCV?

Hey Chuck, I haven't run the car yet without the pcv hooked up. I need another breather and I'll give it a try. How's Chickie?

TVR383
From advices received on this forum I made a test wich was to decellerate (on compression)from ,lets say 60 mph, to 15-20 miles per hour then pressed hard on the accellerator...boy did ever a smoking cloud came out the exhaust then.....till then I never had such smoke from the exhaust under any situations!

I tried this. I accelerated in 3rd gear from 30 mph or so up 6100 then shifted into 4th and ran it up to 6000 rpm (about 125 mph) and let off and coasted to 50 mph or so and no smoke. There is no smoke at start up and I can't really see anyhting out the pipes. But I'll try it again cuz its fun.
Steve
 

·
Super Moderator
Joined
·
6,623 Posts
Make sure you run a road tube that gets airflow under the car, it gets smelly (and explosive!) to let the fumes just dump into the engine compartment.

What works well is jamming a long 1/2" tube (Umbella tube etc. Be creative! :) ) in between the exhaust manifold and running down the block just below the oil pan. Bend it as you install it and will hold there. Works well in cold weather because the manifold heat keeps the tube from freezing up, lots of water vapor in there.

A 45 degree cut on the end facing rearward adds a finishing touch that is effective at drawing fumes out of the engine...except stopped.

It's called the Canadian Prairie Boy pitot tube emission control device.:thumbup:

P.S. Chickie is around here somewhere?:welcome:
 

·
Registered
Joined
·
415 Posts
Discussion Starter #6
Correct me if I'm wrong Chuck but that will also get you 20 horsepower. I'm remember doing that back in the 70's to my 69 Impala and 73 Firebird. I think plugging off vacuum lines was worth 5 hp ea. If you were lucky enough to drive an early 80's Malibu with a Q-jet you could make serious power. Well, the cops go in coffee break at 9:30 so I'll head out then for a burn and see what happens.

Steve
 
1 - 6 of 6 Posts
Top