Valves + oil + stuff
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Joined: Feb 2002
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From: Lutz FL
Valves + oil + stuff
On my 70 mile each way trip to Race Rock sunday, I blew thru around a quart of oil :eek: :eek: :eek: .. No leaks, finally fixed them all, but this is even worse in its own way. My oil pressure gauge reads around 40 at idle hot, and 80 above 1500 rpms. My wife was travelling behind in the other car, and said that occasionally she could see a puff of smoke from the drivers side (got sidepipes on). So I'm sorta thinking its likely to be in need of a valvle adjustment as the engine was put together around 7-8 years ago (but only around 25,000 miles since then).
Any other ideas on what it is likely to be (besides ring blowby which I hope it isn't, but need to borrow a compression gauge I guess) and any suggestions as to an easy way or a tech paper on doing the valve adjustment?
Any other ideas on what it is likely to be (besides ring blowby which I hope it isn't, but need to borrow a compression gauge I guess) and any suggestions as to an easy way or a tech paper on doing the valve adjustment?
Drifting
Joined: Sep 1999
Posts: 1,411
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From: Wylie TX
Re: Valves + oil + stuff (Black68Vette)
A bad valve adjustment cannot cause oil consumption. If your burning oil, it's going to be either from oil getting past the rings and into the combustion chamber, blow by, oil leaking past the valve seals, or oil being sucked into the intake ports due to bad intake sealing.
Burning a qt per 140 miles is a ton. I'd pull the plugs and see what they look like. If your burning oil, they will be pretty fouled. This will also tell you which cylinders are burning oil.
Did this engine burn oil in the past 25k miles? If not, has anything been done to it recently?
If it is the valve seals, when it sits for a while and then you start it up, you should see some smoke then it will probably clear up pretty quickly.
To get an idea about blow by, pull pcv valve off the valve cover while running and see if there is a lot of blow by.
Burning a qt per 140 miles is a ton. I'd pull the plugs and see what they look like. If your burning oil, they will be pretty fouled. This will also tell you which cylinders are burning oil.
Did this engine burn oil in the past 25k miles? If not, has anything been done to it recently?
If it is the valve seals, when it sits for a while and then you start it up, you should see some smoke then it will probably clear up pretty quickly.
To get an idea about blow by, pull pcv valve off the valve cover while running and see if there is a lot of blow by.
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From: Lutz FL
Re: Valves + oil + stuff (Chris A)
Nothing new enginewise done.. And no, its hasn't gone thru a quart in the last 2000 miles before this. But this was 70 miles each way at 3500-3600 rpms the whole time. No smoke on startup either...
I'll pull the plugs on that side, and check the sidepipes for whats inside..
If I pull the pcv, what should I expect?
I'll pull the plugs on that side, and check the sidepipes for whats inside..
If I pull the pcv, what should I expect?
Drifting
Joined: Sep 1999
Posts: 1,411
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From: Wylie TX
Re: Valves + oil + stuff (Black68Vette)
Hmm, so it doesn't sound like it's losing any oil at low RPMs, so your going to have to rev it when the PCV is removed. If your getting excessive blow by, you will see a good amount of smoke leaving the valve cover. If you see a very small thin mist of smoke, your OK.
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From: Lutz FL
Re: Valves + oil + stuff (Chris A)
Will a compression tester tell me if I am getting ring blowby?
Also I guess I have a PCV on one side, and breather on the other. The breather is on the side that smokes. Could that be it too? I'll pull it in check it too...
Ok, actually I lied, there was some engine stuff done. I just forgot. I replaced the fitting that goes from the block to the oil pressure sender as the old one was leaking slightly, and I adjusted timing and carb air/fuel mixture, but that was all...
[Modified by Black68Vette, 5:18 PM 4/4/2002]
Also I guess I have a PCV on one side, and breather on the other. The breather is on the side that smokes. Could that be it too? I'll pull it in check it too...
Ok, actually I lied, there was some engine stuff done. I just forgot. I replaced the fitting that goes from the block to the oil pressure sender as the old one was leaking slightly, and I adjusted timing and carb air/fuel mixture, but that was all...
[Modified by Black68Vette, 5:18 PM 4/4/2002]
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From: Lutz FL
Re: Valves + oil + stuff (Chris A)
Heres a pic of the plugs.. looks like I am running a bit lean, but not sure if its really fouled bad.. all of them are about the same carbonwise
[Modified by Black68Vette, 6:05 PM 4/4/2002]
[Modified by Black68Vette, 6:05 PM 4/4/2002]
Melting Slicks
Joined: Nov 2000
Posts: 2,663
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From: Palm Harbor FL
Re: Valves + oil + stuff (Black68Vette)
You say the engine was done 7-8 years ago. Have you had it since then? Have you ever re-torqued the manifold bolts? The fact that your wife indicated it was intermittent smoke leads me to believe that it's not rings. You should check the manifold bolts before you go ripping into anything. If the manifold isn't torqued properly, you could be sucking oil in there. Just a hunch. Also, as an inexpensive fix, you could try pulling and re-seating the manifold with new sealant, etc. to see if that does the trick. Just some cheap ideas. :D
[Modified by 79MakoL82, 3:13 PM 4/4/2002]
[Modified by 79MakoL82, 3:13 PM 4/4/2002]
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Thread Starter
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Joined: Feb 2002
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From: Lutz FL
Re: Valves + oil + stuff (79MakoL82)
Hmm the manifold hadn't crossed my mind, but makes sense. I've only had the car a little over a year now, but have good documentation on the car up to the last bumbling owner, who only had it a year...
Darn, if only I had a job, it would be a good excuse to buy and throw an air gap on her, instead of this torker :D :D
[Modified by Black68Vette, 10:05 PM 4/4/2002]
Darn, if only I had a job, it would be a good excuse to buy and throw an air gap on her, instead of this torker :D :D
[Modified by Black68Vette, 10:05 PM 4/4/2002]
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Valves + oil + stuff (Black68Vette)
I always go for the cheapest possibility first. :eek: If the cheapest fix doesn't work, then I try the next cheapest. :D but seriously, I have read other posts from people who were eating oil, and a few people have found that it was the manifold. If the engine was re-built, the manifold should have been re-torqued shortly after. It's makes sense to check your manifold bolts torque once a year. If re-torqueing them doesn't work, then I would get some new gaskets and try re-seating the manifold. That's a whole different issue (cleaning out the thread holes, sealant on the bolts, etc.), but re-torqueing is FREE!!!
Good Luck. :cheers:
Good Luck. :cheers:
Thread Starter
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Joined: Feb 2002
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From: Lutz FL
Re: Valves + oil + stuff (79MakoL82)
Should I bring a torque wrench along for saturday at Tia's ? ;)
After trying everything else, its either the manifold, or all my rings gave out at once.. cause what fouling there is seems pretty consistent cylinder to cylinder. Although actually that shouldn't be true if it was the manifold either huh? Crap, damn thing, always a hassle. But pretty ;)
After trying everything else, its either the manifold, or all my rings gave out at once.. cause what fouling there is seems pretty consistent cylinder to cylinder. Although actually that shouldn't be true if it was the manifold either huh? Crap, damn thing, always a hassle. But pretty ;)
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Valves + oil + stuff (Black68Vette)
Should I bring a torque wrench along for saturday at Tia's ? ;)
You initially said that your wife saw intermittent smoke on the drivers side but not on the passenger side, so I still think it could be the manifold. Give it a try. As I said, re-torqueing is free, and re-seating is cheap. That always makes sense in my book :cheers:
Drifting
Joined: Sep 1999
Posts: 1,411
Likes: 1
From: Wylie TX
Re: Valves + oil + stuff (79MakoL82)
If retorquing doesn't work and you do pull the manifold, you should see on the gasket where the oil is leaking and this will tell you if it is your problem.
I'm kinda fighting some oil consumption too (1 qt/ 1k mi) where all except my front plug on each side (1 & 2) are oil fouled with the back ones (7 & 8) the worse. I've ruled out my valve seals because I get 0 smoke at startup. I was at first blaming the rings not being seated, but now I'm leaning towards a bad manifold seal. I'll probably live with it for a little while longer and then pull the manifold and have a look.
I'm kinda fighting some oil consumption too (1 qt/ 1k mi) where all except my front plug on each side (1 & 2) are oil fouled with the back ones (7 & 8) the worse. I've ruled out my valve seals because I get 0 smoke at startup. I was at first blaming the rings not being seated, but now I'm leaning towards a bad manifold seal. I'll probably live with it for a little while longer and then pull the manifold and have a look.
Drifting
Joined: Sep 1999
Posts: 1,411
Likes: 1
From: Wylie TX
Re: Valves + oil + stuff (Black68Vette)
I'm pretty sure it is 30 ft/lbs and the pattern is:
8--7--------2--3----------9--10
------------------------------------------> Front of engine
6--5--------1--4---------11--12
[Modified by Chris A, 10:53 AM 4/5/2002]
8--7--------2--3----------9--10
------------------------------------------> Front of engine
6--5--------1--4---------11--12
[Modified by Chris A, 10:53 AM 4/5/2002]
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Valves + oil + stuff (Black68Vette)
I don't have them, but I'm sure they're in the shop manual at home. :rolleyes: Also remember, don't torque them to full spec in one shot, do it in increments following the pattern, ie 10 then 20 then 30
Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Valves + oil + stuff (Black68Vette)
H-m-m-m-m-m. Good question. Initially, I was going to say no, because that could just create problems where there were no problems before. Then I thought, "but what if some bolts are over-torqued"? Here's my opinion. Just torque them up, don't loosen them. If the problem still exists, I would say take the bolts out, and re-seat the manifold with new gaskets and sealant. That's my opinion. Others may disagree (wouldn't be the first time :D ). I'm off to lunch now. I'll check the torque specs/pattern while I'm there.
[Modified by 79MakoL82, 11:25 AM 4/5/2002]
[Modified by 79MakoL82, 11:25 AM 4/5/2002]