Oil Smoke driving me crazy

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Raybo
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Oil Smoke driving me crazy

Post by Raybo »

Brand new 383 I just built for a truck. AFR heads flat top engine. Runs great, once its up to operating temps it has some smoke coming from exhaust on both banks. I changed intakes, gaskets looked oily and there was oil in runners. Same thing happened. Checked studs to make sure they had sealer. Comp check looks good. I am pulling the intake again first thing in the morning to reseal. If that doesn't fix it I am tearing it down.

Just wanted to run it by some of you to see what you may think.
dynoflo
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Re: Oil Smoke driving me crazy

Post by dynoflo »

there are many threads on here concerning intakes not sealing. check them out
Raybo
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Re: Oil Smoke driving me crazy

Post by Raybo »

I was looking for other ideas too.
PRH
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Re: Oil Smoke driving me crazy

Post by PRH »

If you’re running a pcv valve, try removing it and installing another breather.

Check to see if the hose has oil residue in it.

I’ve seen it where oil would run out of the pcv hose.
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Re: Oil Smoke driving me crazy

Post by Truckedup »

Given thought to oil getting past the rings or valve stems?
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Raybo
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Re: Oil Smoke driving me crazy

Post by Raybo »

Truckedup wrote: Sun May 17, 2020 10:38 am Given thought to oil getting past the rings or valve stems?
I have, If it sits it blows out a big puff of smoke on start up. when I took the intake off it had a puddle of oil behind the intake valve. Brand new AFR heads.

Leak down test is next. Its a 10.5:1 383 on 93 octane. I could have broke some pistons but unlikely.
Raybo
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Re: Oil Smoke driving me crazy

Post by Raybo »

PRH wrote: Sun May 17, 2020 10:35 am If you’re running a pcv valve, try removing it and installing another breather.

Check to see if the hose has oil residue in it.

I’ve seen it where oil would run out of the pcv hose.
Im running open breathers on VC
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Re: Oil Smoke driving me crazy

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rebelrouser
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Re: Oil Smoke driving me crazy

Post by rebelrouser »

Your oil smoke can have several causes, intake leaks, faulty valve stem seals, rings that did not seat. etc. You are getting good advice on checking those items.

I never run open breathers on anything any more, and the open breathers most likely are not the whole issue, but getting rid of blow-by gasses is part of the engine package. blow-by gases will make your oil get dirty quicker, promote moisture contamination, and cause oil consumption. If you have pressure in the crankcase, you have pressure on the bottom side of the ring, on the intake stroke, you have vacuum on the topside of the ring, so oil wants to go into the combustion chamber. At a minimum on a street engine run a PCV system, or backfire valves in the headers. You can look at the number of OEM service bulletins on oil consumption, and redesigns of valve covers and PCV systems to know their can be a lot of issues with crank case pressure causing problems. The old draft tube used air rushing by it to create a suction to help vent the crankcase better.
1972ho
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Re: Oil Smoke driving me crazy

Post by 1972ho »

Check the fit of your intake with no gasket and see if there are gaps while you have it off it may need to be surfaced.
Walter R. Malik
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Re: Oil Smoke driving me crazy

Post by Walter R. Malik »

Raybo wrote: Sun May 17, 2020 10:30 am I was looking for other ideas too.
I would check the intake rocker studs to make sure they have a good thread sealer where they thread into the head.

Personally, I use "Right Stuff".
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70MC
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Re: Oil Smoke driving me crazy

Post by 70MC »

What part number intake gasket are you using? From the pics it looks like a stock replacement gasket, I do believe they recommend performance gasket with aluminum intakes.
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Re: Oil Smoke driving me crazy

Post by dfarr67 »

I had my own issues with my AFR headed 383, I used steel core FelPro intake gaskets.
- Edelbrock TPI base on previous 355 did not have any issues with being zero decked, FIRST TPI base needed to be machined as I did not want to touch AFRs, still had rear china wall issues fixed with 'the right stuff' and attention.
- I feel there may be a cylinder glaze issue with oil found in plenum floor.
- stuffed pcv baffles on factory valve covers with ss wool.
- purchased (could only afford with group buy) Wagner pcv valve, along with a quality air/oil separator tank.
Haven't driven enough to guage difference yet, but did not strike me as an oil burner and no puffs of smoke- it was more evident I think in tuning last year with detonation. We'll see.
- no issues with supplied valve seals.
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Re: Oil Smoke driving me crazy

Post by dfarr67 »

Walter R. Malik wrote: Sun May 17, 2020 11:42 am
Raybo wrote: Sun May 17, 2020 10:30 am I was looking for other ideas too.
I would check the intake rocker studs to make sure they have a good thread sealer where they thread into the head.

Personally, I use "Right Stuff".
If I recall with these AFRs- even though I did use thread sealer- the threads are blind.
rebelyell
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Re: Oil Smoke driving me crazy

Post by rebelyell »

Also, perhaps rings (particularly Second) are installed wrong ?

Second intended to scrape oil down; if ring's upside-down, it can push oil up.

Hope it's simply leaking intake gaskets.
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