Engine smokes quite a bit under heavy throttle
Thread Starter
Pro
Joined: Mar 2001
Posts: 512
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From: Greensboro NC
Engine smokes quite a bit under heavy throttle
I replaced my motor after spinning a bearing. I swapped heads from my old motor to the current motor. While I had the heads off, I refreshed them by putting new valves, seals and springs in. Under heavy throttle and high rpm, my car smokes like there's no tomorrow. It doesn't do it under light loads or idle and it is blue smoke. I have an LS6 intake and the updated valley cover/PCV system. One thing I'm going to do tonight is remove my rockers and silicone the bolts that go into the intake runners to make sure I'm not sucking oil there (though I don't know if it could suck enough there to cause it to smoke like it does). Anyone have any ideas what would make one smoke heavily under high load and RPMs?
Thanks,
Frank
[Modified by QwikSilvr, 10:19 AM 11/11/2003]
Thanks,
Frank
[Modified by QwikSilvr, 10:19 AM 11/11/2003]
Team Owner
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From: Various places in Southern California.
Re: Engine smokes quite a bit under heavy throttle (QwikSilvr)
In my experience, high load and RPM oil burning is usually ring sealing. Did you follow a break-in procedure?
To be sure, I'd do a leak down test before and after squirting some oil into the cylinders.
To be sure, I'd do a leak down test before and after squirting some oil into the cylinders.
Team Owner
Joined: Jul 2001
Posts: 21,398
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From: Various places in Southern California.
Re: Engine smokes quite a bit under heavy throttle (QwikSilvr)
At 10K miles I wouldn't have done anything for a break-in either.
Try the leakdown test with and without a squirt of oil into the cylinders. That will probably tell you if there is a ring sealing problem. If there's no ring sealing issue (i.e. the leakdown results are the same before and after you put in in the oil) then you've likely got bad or missing valve seals.
Try the leakdown test with and without a squirt of oil into the cylinders. That will probably tell you if there is a ring sealing problem. If there's no ring sealing issue (i.e. the leakdown results are the same before and after you put in in the oil) then you've likely got bad or missing valve seals.
Thread Starter
Pro
Joined: Mar 2001
Posts: 512
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From: Greensboro NC
Re: Engine smokes quite a bit under heavy throttle (Duck916)
Duck, I've never done a leakdown so I'll have to look into what is required to do one. As far as the valve seals are concerned, I put on new ones myself.
At 10K miles I wouldn't have done anything for a break-in either.
Try the leakdown test with and without a squirt of oil into the cylinders. That will probably tell you if there is a ring sealing problem. If there's no ring sealing issue (i.e. the leakdown results are the same before and after you put in in the oil) then you've likely got bad or missing valve seals.
Try the leakdown test with and without a squirt of oil into the cylinders. That will probably tell you if there is a ring sealing problem. If there's no ring sealing issue (i.e. the leakdown results are the same before and after you put in in the oil) then you've likely got bad or missing valve seals.
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Re: Engine smokes quite a bit under heavy throttle (QwikSilvr)
Sounds like rings. Hope you find that it is something much easier to fix.
Racer
Joined: Sep 2002
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From: Austin Tx
Re: Engine smokes quite a bit under heavy throttle (QwikSilvr)
Blue smoke at WOT is not comming from the intake valves(1), and not likely comming from the exhaust valves(2), therefore DUCK916 is most likely correct. Either way, its going to come apart again?--right!
(1) high pressure in intake ports at WOT does not pull oil down the valve stems; unlike high vacuum at closed throttle and high RPMs.
(2) Exhaust valves guides almost always leak back to the heads and not into the headers since there is high pressure in the exhaust gasses compared to the pressure in the heads.
It might NOT be the rings, it could be that the cylinders are out of round and this makes it impossible for the rings to achieve a seal (ask me how I know).
(1) high pressure in intake ports at WOT does not pull oil down the valve stems; unlike high vacuum at closed throttle and high RPMs.
(2) Exhaust valves guides almost always leak back to the heads and not into the headers since there is high pressure in the exhaust gasses compared to the pressure in the heads.
It might NOT be the rings, it could be that the cylinders are out of round and this makes it impossible for the rings to achieve a seal (ask me how I know).
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