Hybrid96EK

This is more or less a last chance to see if I possibly overlooked something here.

The engine has 700 miles on it since a FRESH rebuild... Honed the block, new OEM rings, new OEM bearings on mains, ACLS on the rods, B18C1 block, ITR rods and pistons, stock crank, stock GSR head with omni springs and retainers, stock cams, stock ITR oil pump, Skunk2 intake, ITR throttle body. Shouldn't be anything else of importance in there...

Here is the problem. 700 miles so far on the "break in". The piston tops (if inspected through the spark plug hole) are ALWAYS wet. Even after just shutting down or sitting. The "wetness" never evaporates. The car was street tuned with a wideband by myself since I first fired it up. Runs fine with the exception of an oil burning smell. The smell seems to be magnified if I engine brake before coming to a complete stop. If I sit at the stop sign or whatever, I can smell burning oil. Smells a LOT like someone put oily hands on the header, or poured oil onto something very hot. No visible leaks, no catalytic converter on the car. Oil DOES drop down on the dipstick, especially if I wind the car up to 8 grand or so. I do not see any smoke out the rear window or mirror and if I rev the car in the garage, I get no blue smoke... some black, nothing big. With everything I had to go on, I suspected valve stem seals. I went ahead and replaced the stem seals with NEW OEM ones. Problem was the same. PCV system was completely checked as well. I cleaned the valve and reinstalled it. Leakdown is 6%, compression shows 250 on each cylinder. At this point, I am out of ideas. The car seems to have excellent power (haven't been to the track) and runs good overall. Fuel economy is 25mpg with a mix of city and highway driving. Plugs look excellent. Always clean, good color, etc. Piston tops are always wet and have what I would consider a good amount of carbon build up considering the low mileage. Does anyone have any ideas or things I might have possibly missed. I am open to all ideas...

00Red_SiR

tough one... isn't 6% leak down a little high for a motor like yours? I would think it would be somewhere around 2% or less? I'm wondering if you might have a small crack somewhere? cylinder wall? head? head gasket? between the cylinders and oil passageway? Then when the car heats up and the crack expands and more oil is lost vs when it cools down and you do a leak down or compression test when it might seal better? other than that, I'm at a loss..

Combustion Contraption

6% is relatively tight, but not for a 700 mile rebuild. If you didnt hear air escaping through intake / exhaust, there could be a problem with your ring pack. Did you check your end gaps? Especially the 2nd ring. Technically its called a 2nd compression ring, but it really acts as an oil control ring also. If its overheated at all, or the gap was too small to begin with this could be the problem.

mar778c

iTrader: (1)

Sounds like oil control rings. Did anything happen during the piston install? If the skirts were scuffed or the oil control rings were bent or the compression rings were installed upside then you will have a oil consumption problem.


If this are rs machine pistons, I would get a new set and flexhone the cylinder walls and re-install.

Hybrid96EK

Brand new OEM rings and OEM ITR pistons. The cylinder block was mic'd and found to have little to no wear. I had it honed, but no, I did not check ring gaps as I have never had a problem if the block mic's out correctly with OEM rings. The rings were NOT installed upside down or anything, I am 100% sure.

As for the leakdown, my tester I think it hosed. You're supposed to set the regulator to 0psi when you connect the air hose and I forgot to a few times. The needle has been pegged more then once. Anyways, I have NEVER had an engine read less then 6% on this gauge. I can clearly hear the leakage IS past the rings. As for it needing to be 2%, I have had engines with 30+% leakdown on my gauge that don't have these problems. I highly doubt its a ring issue. If it was, the cylinder edge should be clean from the oil passing. I would also have darkening of the oil as the carbon from combustion passes into the oil, which I do not have. Current oil has like 500 miles on it and is VERY clean.

.I.Need.Money.

So, how much oil are you consuming?

Hybrid96EK

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .I.Need.Money. &raquo;</TD></TR><TR><TD CLASS="quote">So, how much oil are you consuming? </TD></TR></TABLE>

If I run the car onto the high cam, I could easily kill anywhere from 1/4 to 1/2 a quart in a day without much trouble. If I just cruise normally and shift no higher then say 5k it doesn't seem to use more then about 1/4 per week which is good for about 100 miles.

.I.Need.Money.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid96EK &raquo;</TD></TR><TR><TD CLASS="quote">

If I run the car onto the high cam, I could easily kill anywhere from 1/4 to 1/2 a quart in a day without much trouble. If I just cruise normally and shift no higher then say 5k it doesn't seem to use more then about 1/4 per week which is good for about 100 miles.</TD></TR></TABLE>

Yikes... and you're not seeing any smoke???
When my motor was consuming oil it smoked horribly.

Anyway, I had my motor freshened up. New pistons, rings, gaskets, seals, bearings, the works. Got it back, and it was still smoking! We did a conmpression and leakdown test. Got good #'s, but it was still consuming oil. So I had them re-ring it. Problem solved... Not sure if that's your problem, but there's a good chance it is your rings. What oil are you using?

mar778c

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .I.Need.Money. &raquo;</TD></TR><TR><TD CLASS="quote">
Anyway, I had my motor freshened up. New pistons, rings, gaskets, seals, bearings, the works. Got it back, and it was still smoking! We did a conmpression and leakdown test. Got good #'s, but it was still consuming oil. So I had them re-ring it. Problem solved... Not sure if that's your problem, but there's a good chance it is your rings.</TD></TR></TABLE>

Exactly, what I said earlier. If this are cast I would just get a new set and be done.

Combustion Contraption

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .I.Need.Money. &raquo;</TD></TR><TR><TD CLASS="quote">

Yikes... and you're not seeing any smoke???
When my motor was consuming oil it smoked horribly.

Anyway, I had my motor freshened up. New pistons, rings, gaskets, seals, bearings, the works. Got it back, and it was still smoking! We did a conmpression and leakdown test. Got good #'s, but it was still consuming oil. So I had them re-ring it. Problem solved... Not sure if that's your problem, but there's a good chance it is your rings. What oil are you using?</TD></TR></TABLE>

ban kai.

.I.Need.Money.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Combustion Contraption &raquo;</TD></TR><TR><TD CLASS="quote">

ban kai.</TD></TR></TABLE>

You know Ban Kai!?

Hybrid96EK

Somewhat of an update here:

I took off the injectors and looked down in the intake manifold. The intake valves have what appears to be oil all over the face of the valves. A couple of them have a carbon like build up as well. At this point, since the stem seals are new, I am leaning towards worn guides. I really don't think its the rings. If the rings were leaking oil this badly, the piston tops should be "cleaner" then they currently are.

Evs-One

I vote for guides.

I've had a few issues sounding just like this- ended up getting new guides and problem solved!

Guides like to go bad after years of 8k rpm redline

Hybrid96EK

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Evs-One &raquo;</TD></TR><TR><TD CLASS="quote">I vote for guides.

I've had a few issues sounding just like this- ended up getting new guides and problem solved!

Guides like to go bad after years of 8k rpm redline </TD></TR></TABLE>

Yeah. Everything at this point just points to worn guides. The engine smoked before and I changed the rings. The rings had less then 5k miles on them... still smoked. Now with the OEM rings, leakdown has improved but the smoking has gotten worse. I believe it is due to higher cylinder vac pulling in more oil past the stem seals. The seals are nothing more then wipers which still allow for the passage of SOME oil. Larger amount of pressure on one side drawing the oil past would make sense for what I am seeing. I have another head out there that needs a valvejob. I will check stem to guide measurements and get the sats ground and try it out.

Combustion Contraption

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .I.Need.Money. &raquo;</TD></TR><TR><TD CLASS="quote">

You know Ban Kai!? </TD></TR></TABLE>

I do exist outside the world of automotive-stuff.