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Here's a check list from Hastings:
Hastings oil consumption check list.
It's the second ring that has the taper. If a taper face ring is installed upside down it will scrape oil upwards not down.
 

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For comparison here's a barrel faced moly top ring. You could have a broken ring from improper installtion and still have good compression.
 

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stock z/28 said:
Does your engine have a lot of blow by?
This is what I'm trying to figure out. It smokes some, mostly out the left side. And it's definitally consuming oil.

Just not sure why it's consuming oil. I did a compression check, that looked good. I also did the pressure check, and that looked good.

Machine shop installed new valve seals and checked the guides before I installed the heads. Heads were used with about 2000 miles on them, previous owner said he didn't have a smoking problem.

Rings are Hastings.
 

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If it's smoking from one side it may be the intake gasket isn't sealing on the side closet to the valley and sucking oil into that side of the engine.
I'd pull the intake and look in the ports and around the bottom sealing surface.
Re-do the intake gasket and make sure you install it carefully and torque in the proper sequence.

Was the block zero decked or the heads milled? If so you may have a poor fitting intake that needs milling to fit.
 

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Paul Wright said:
If it's smoking from one side it may be the intake gasket isn't sealing on the side closet to the valley and sucking oil into that side of the engine.
I'd pull the intake and look in the ports and around the bottom sealing surface.
Re-do the intake gasket and make sure you install it carefully and torque in the proper sequence.

Was the block zero decked or the heads milled? If so you may have a poor fitting intake that needs milling to fit.
Yeah, it was zero decked. I certainly hope this may be the problem. I really don't want to pull this thing out.
 

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The way I see it...

Another important part of the whole testing equation that may be missing here (as discussed thus far) is...compression and leakdown tests are comparative and subjective to each single engine tested. They are supportive of "cylinder to cylinder" test results, and are great comparsion tools for troubleshooting what cylinder is potentially at fault, but no two tests (nor engines) are alike. Regulator types / condition, oil viscosity, build tolerances, wear tolerances, free starter crankings speeds, temperature, hose and fitting restrictions and so on, support a myriad of variables.

Even then you are only testing with-in the cylinders pressurized boundary! Valve stem / seals, certain cylinder head cracks and the induction side of the house for instance are not even addressed.

Case in point...one may find what appears to be correct compression reading results for instance, only to have a worn engine display equally through out each cylinder. In other words, the readings are all close and "in spec" but the rings all blow by equally across the board.

There's nothing around that can compete with "open and inspect" when it comes down to determining TRUE engine mechanical condition. Leak down and compression tests at best will tell you something is wrong. But you already knew that ( IE, a miss, leak, noise, smoke, low oil pressure, etc) and guess what....you're going to have to "go in" any ways.
 

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Just an update.

I pulled the intake, and indead oil was getting past it into the intake runners. Every runner had oil going into it. So I change the intake gaskets from standard port size, to FeldPro 1207. These matched my head port size better, but may have been a little to big. But not big enough to not seal the port. The 1206 would of probably been a closer match. Both would be bigger then the Performer RPM's port size.

So after changing the gaskets, the smoke was gone, and the car ran much better. For a little while. After I drove it around awhile, I came back and all was still fine. Later on I started the car again, and it seems to be smoking again, like it was before.

We applied some sealer to the gasket, installed the maifold with a couple bolts, let sealer dry, removed manifold to check for gasket shift. Then torqued the manifold to 20 ft/lb.

Block was only milled slightly. And the manifold holes line up just fine with the head bolt holes.

Any other suggestions? Thinking of trying some Edelbrock Gasgasinch to seal the gasket in place.
 

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I guess I was right on this one.

I thought the block was milled to Zero deck? .025" isn't a slight amount.
I'd check the manifold for fit without the gaskets. It may have a wider gap at the bottom than the top. You may have to mill the intake.
BHJ makes a checking gauge to see if the intake will fit after machining. See pix

You need to use the correct gaskets. "Close" is not good enough.
Also don't use the rubber china wall gaskets. They can add too much support at the ends. Use Red RTV. I think the torque spec is actually 35 ftlbs. Also make sure you torque in proper sequence.
Tightening one side then the other is a sure way to lift one side.

Alot of people underestimate the importance of intake fit. I sometimes spend days finnessing an intake manifold to fit correctly.
 

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My car sucked an intake gasket up once. It seems that the car had another issue that went along with it. It ran hot, or had detonation from the oil in the mixture. I'm not really sure what it was now. I'm sure someone else could fill me/us in on that.
 

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Thanks for the info.

Actually, the block was just squared. Not Zero-Decked.

My SBC book by Vizard states 20 ft/lb, but I'll see what else I can find on that.

Yes, the FeldPro gaskets I used did have the blue rubber sealant deals around the ports.

What gasket do you recommend?
 

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When I built my 406 a similar problem arise with oil
consumption on my engine. I chased comp, intake
gaskets, etc for some time trying to fix problem. I have
Trick Flow Alum. heads, a call to thier tech line cured
the problem. The intake rocker arm studs penetrate the intake
runners, and must be sealed properly. I had used ARP
stud sealer which after use started washing off! They
recomended Permetex Aviation sealer only as stated
in thier assembly instructions! (yea I know)

I see from your previous post you have Pro top Line
heads? This may not apply to your problem, but many
after market heads are similar so I thought I would
mention it. Hope you find a fix!

Good luck, Rich
 

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I would'nt discount the possibility of having both problems.
If you are happy with the manifold gasket replacement that
you did this time I would look at resealing the studs since
you are still getting oil. It would be something to eliminate
as a problem without getting into engine disassemby.
Good luck, Rich
 

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Paul Wright said:
I guess I was right on this one.

I thought the block was milled to Zero deck? .025" isn't a slight amount.
I'd check the manifold for fit without the gaskets. It may have a wider gap at the bottom than the top. You may have to mill the intake.
BHJ makes a checking gauge to see if the intake will fit after machining. See pix

You need to use the correct gaskets. "Close" is not good enough.
Also don't use the rubber china wall gaskets. They can add too much support at the ends. Use Red RTV. I think the torque spec is actually 35 ftlbs. Also make sure you torque in proper sequence.
Tightening one side then the other is a sure way to lift one side.

Alot of people underestimate the importance of intake fit. I sometimes spend days finnessing an intake manifold to fit correctly.
Paul, when I put the intake on the engine without gaskets, do you know what kind of clearances I should have between the intake and the heads?
 

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MarkM68 said:
Paul, when I put the intake on the engine without gaskets, do you know what kind of clearances I should have between the intake and the heads?
None, but it will sit lower. If you have gap a the bottom but it hits at the top edge then it will probably suck oil off the lifter galley.
Some shops like to have an interferance angle so the bottom sinks into the gasket first then the top is torqued outward.
 

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DriveWFO said:
Does Craftsman make a leakdown tester? I couldn't find it on Sears.com.
I thought I saw one at a Sears Hardware store but I could be mistaken.
Summit and Jegs both have them as well Snap-on and others like Moroso and B&B.
 
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