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Has anybody ever had a problem with a high pressure oil pump causing a engine to smoke during a shift or letting off the throttle at high rpm? If I just lay into it the car won't smoke but it blows out smoke during the shift or pretty any time I floor it let out and when I floor it again it smokes. I thought I was just having blow by or a valve seals was messed up but I took the intake I had off to do a fast 102 swap this weekend and there is oil in every port which would lead me to a pcv issue but I have a rev extreme dual valve can and a ls6 valley plate. The pcv lines are pretty clean but the intake had oil all in the inside when I pulled it off. My thought was maybe the high pressure oil pump was pumping to much oil to the top of the heads and when I let out of the gas at high rpm and the motor went into vacuum it was pulling oil through the valve seals into the intake. Just a thought, this is driving me crazy at this point. The car runs hard as hell but I can get it to stop smoking.
This is what the heads looked like when I pulled the intake off this weekend.
Whats your oil pressure at high speed? Too much oil pressure is not a good thing contrary to popular belief. It very well could be a drainage issue as well because your heads are getting either a lot of oil pumped up into them and/or they are not draining back normally. Check the drain ports on the heads and make sure they are fine. is the pcv valve blocked? Were the valve seals replaced recently?
I'd have to pay more attention during a pull but I think around 70 psi at 6500 rpm. It idles at 45 psi hot. Valve seals were done last year when I ported the heads. I hope I got it figured out. The rocker bolts that go down in the intake port only had red loc tite on them and were covered in oil when I pulled them out. Hopefully I can seal them up with some thread sealer and it will be good.
Sealing the rocker bolts will have zero effect on the intake taking in oil. they were covered in oil because the heads were saturated in it. Try and look at those seals again now that you have the rollers out. What type of seals did you use for the valves?
You can't really see the valve seals with the dual springs on. They were brand new btr valve seals.
I see, its just I would put that on my list of suspects, that's an awful lot of oil getting into the combustion chamber to not rule it out, the other side of the coin is possible worn valve guides. Do the tips of the rollers all look the same wear pattern?
Last edited by midnight01; Jul 5, 2016 at 08:27 PM.
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the rocker bolt holes don't go into the combustion chamber so it isn't necessary to seal them up... I just took mine out and they had oil on them too, no big deal... is that a comp or btr trunnion kit?... looks like it to me, if you haven't seen the thread I started on these prematurely wearing check it out https://www.corvetteforum.com/forums...s-of-pics.html
When the engine is at normal operating temperature, can you take the oil filler cap off and see any smoke coming out of the filler tube? If so, you might have a broken ringland (more common than you think). I see you've installed a high pressure pump and other mods. So what have you done to this motor? Spray? FI? If you have a broken ringland, you can have too much crankcase pressure (only increased by the high pressure pump) and it pushes the oil thru the pvc valve and back into the throttle body to be burned up. I think it would be prudent to do a pressure check on every cylinder. Report back.
No spray no FI. Just a basic ported 243/ sns tq max stage 3 cam/ fast 102 setup. It's done it every since I did the heads/cam setup. I changed the plugs the other day and they were all clean. There doesn't seem to be very much oil in the pcv hose going to the intake from the catch can. Car makes great power I'm just tired of the smoke.
the rocker bolt holes don't go into the combustion chamber so it isn't necessary to seal them up... I just took mine out and they had oil on them too, no big deal... is that a comp or btr trunnion kit?... looks like it to me, if you haven't seen the thread I started on these prematurely wearing check it out https://www.corvetteforum.com/forums...s-of-pics.html
Originally Posted by hodge9386
No spray no FI. Just a basic ported 243/ sns tq max stage 3 cam/ fast 102 setup. It's done it every since I did the heads/cam setup. I changed the plugs the other day and they were all clean. There doesn't seem to be very much oil in the pcv hose going to the intake from the catch can. Car makes great power I'm just tired of the smoke.
those two combined are what i think the problem is if it's not the valve seals. and those are super easy to replace if you just wanted to rule them out while you have the rockers out.
so while with factory heads the bolts wouldnt leak into the combustion chamber, they most certainly would if you have the rocker lump removed (which is the first thing done with porting the heads).
seal those things up with some ARP thread sealer and see what it does!
So I didnt fix all the issues but it is much better. This vid was this weeked and you can see when I shift it blows a puff of smoke. It used to be much worse and smoke all during the pull.
So I didnt fix all the issues but it is much better. This vid was this weeked and you can see when I shift it blows a puff of smoke. It used to be much worse and smoke all during the pull.
one of two things:
1) valve guides
2) its an LS engine
mine smokes at least like that when im on the track, or doing what you were doing in that video (that was clearly in Mexico). as long as you arent painting the bumper, i dont really question it.
unless that's through cats? if thats through cats thats a bit more than mine does. mine's straight through.
reason i say that is because my first ever track day, it smoked a little.. then more.. then i was black flagged for smoke. swapped to ported/polished 243 heads later on, and problem went away completely. was definitely valve guides. i do use the arp thread sealer on the rocker pedestals, and the hole clearly punctures into the intake chamber, so no issues there.
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high pressure oil pump causing car to smoke?
