Help! Lots of going through the PCV on new engine

Hi guys, I´ve searched the Hamb but couldn´t find an answer to my problem.

I´ve built a 383 SBC for a buddy´s 50 Merc using a Summit Kit with KB pistons and all new parts, had the block bored and honed. The engine ran fine and quiet and had good oil pressure on my gauge.
After the first oil change it burnt all 5 qts of oil within 100 miles. He had no working oil pressure gauge (!!!), but he didn´t care until he heard the engine knock.

I pulled the engine, no leaks anywhere, all main bearings worn to the copper layer and the #1 rod bearing almost gone.
He says the engine didn´t smoke, but the piston tops are black and the plugs fouled.
I checked the piston and ring clearences, they are up to spec.
What could have caused that amount of oil consumption within 100 miles?

I have to rely on what he tells me, so that´s what i can work with. I just don´t want to fix the engine to have it back in the garage within another 1500 miles....

Thanks in advance ! Chris

 

If there was that much of a leak, there would have been a dripping wet underside of the car. If it burned it, there should have been oil pouring out of the exhaust pipe. Something doesn't smell right. I'd put on my Sherlock Holmes hat and see if you can find tell-tale signs that will give you the story that makes the most sense.

I would be inclined to think someone thought to change the break in oil at 100 miles and forgot to put new oil in it, then blame it on oil consumption. Is the same oil filter on it? Are the surfaces of the drain plug showing a wrench has been on it?

 

To burn that much oil in 100 miles you would see the smoke.

Is he sure that he put the oil back in it after the oil change?

 

There is no way. There would have to be a HUGE oil spot or LOTS of smoke. It had to go somewhere.

 

Look IN the oil filter. Has there been any oil through it? It would seem that the filter should be almost full. Sounds like somebody never put any in when they "changed" it as mentioned above. Or, they forgot to put back the the drain plug.

 

I got 50¢ riding on a dry oil filter.

Bob

 

While staring at filter, also check to see if oil in filter is perfectly clean and new...if you leave out a plug in the vertical stack oil gallery, filter will fill up but have zero flow.
Just for reference, also do a compression test (leakdown if available to you) just to see if ring job was no good.

 

I had a Chevy 6-banger in a truck that was good for a quart in 20 miles and the smoke out the exhaust was ghastly as was the blow by under the hood. In this case, given the same ratio, it would have been noticed by just about anyone if the crankcase was ever filled up.

Bob

 

Why would you run a new rebuilt engine without a working oil pressure gauge? More money than brains?

 

"After the first oil change....???" How much oil did it burn up before the change, and how many miles? If it didn't suck it all up the first panful, somebody screwed up bigtime on the oil change.

 

If it's an automatic trans you might check and see if its about 5 quarts over!

 

Anything I say will be a wild-ass guess, but take a look at the valves on the backside thru the ports with a good light, looking for oil that got thru the guides.
This is just another guess, but at least it gets me subscibed to this thread so's I'll get to follow it till you hopefully find the trouble and post the solution for the rest of us.
Bruce Lancaster: I'm familiar with the galley plug you mention, but wouldn't lack of this plug just simply not force oil thru the filter? Would it cause this astronomical oil consumption?
Dave

 

oh i gotta see this

 

My money is on oil wasn't put in. Maybe double gasket on the filter, but you would need ta be an even bigger dumbass not to notice the mess.

 

I broke the engine in on my engine stand , it ran great at 180 degrees of water temp and 60 psi of oil pressure at 2000 rpm, in cold condition it had around 75 psi.

I didn´t see the car myself, I just delivered the engine to the guy who put it in the Merc. Afterall it came out that his oil pressure gauge in the Merc was reading 80 psi with the ignition on but the engine not running, go figure.... so he was driving without a working pressure gauge.

I

I told them to change to oil after 1000 miles. I had changed it already after the first hour of running on my engine stand.There where no oil stains or drips on the mill when i got it back, it looked just like new. The oil had been drained and the filter removed... here rings the bell...!!!

 

here are some pics when I built the engine... maybe one of you guys find an obvious mistake I made that could have caused the failure.




here´s how I mounted the PCV valve.

 

Well since you have it back - it should be real easy to tell if all that oil went into the combustion chambers.

if the oil didn't leak out, if it didnt get burnt, if its not in the trans, or the cooling system.
then there wasn't any oil, That part is not hard to figure out. The hard part is figuring what your friendship is worth.

 

Is that the PCV that alum doohickey? Never seen a pcv on the intake like that. Seems it would suck a lot of flying oil out of the lifter galley and burn it. On the valve cover it's between rockers right? hence, fumes only. JMO. Lippy

 

that should be easy to spot also with the hose coloration and deposits in the intake and cylinders.
if they are clean, very likely they didnt put the oil back in and the friendship is soon to be tested.

 

Most intakes have a baffle under them, same goes for valve covers. You always want to have a baffle when using a PCV valve, otherwise you will pull in more oil than you want to, but to comsume that much oil it that many miles is basically impossible due to the size of the PCV orifice, and the fact that it isn't in operation all the time that the engine is running.

BAUMI,
Based on what you did up front, The only thing that really makes sense is that the guy screwed up and is trying to make it your problem. If he was a real friend he wouldn't pull this crap...

 

ive never torn into a chevy motor, and have little experience with car motors for that matter. motorcycles are my area of expertise and usually when one runs out of oil, the oil pump itself tells the story. can you inspect the oil pumps for damage/inconsistent wear?

 

going to stick around to here the conclusion...hopefully
Cam ok?

 

Try taking the oil pump apart to see if it has been run dry. If it has, it should show some signs of heating and/or other damage.

 

My guess would be the hose on the intake ,Bad rings not seated or broken .Clogged filter .Bad valve guides Or leak and never checked Ran motor to hard after rebuild ,or ran low on oil .Wrong bearings in crank .Also bad oil pump ,Did you change the shaft that went to the distributor .Also could of been leak there .

 

What rings did you use Cast or chromolly .

 

The pcv needs a baffle. I tried that same thing and it did the same thing. Here is what I did.
http://www.jalopyjournal.com/forum/showthread.php?t=399206
I havn't run it yet. It's that or run the pcv in the fill tube.

 

If you confirm that the oil pump was indeed turning, and thus pumping oil, then I believe that you are being lied to. I suspect a failure to re-fill the oil.

Otherwise there would be a small lake or long trail of oil, or a heavy blue haze enveloping some fine Bavarian town somewhere. It would take some heavy denial to miss either one.

Oh, and I run my PCV system off the back of the manifold on my SBC, just like that. I have notice no excess oil consumption whatsoever. Nice almond colored porcelain on all eight.

Oh, and that's a quart about every 2500 miles. Some might call that excessive, but I don't.

 

Thanks guys, things start to make sense now. The PCV is not baffled, but I will make a baffle like Dyce did on his intake. Thnaks for the good info!
Whatsoever I was told that there was no measurable oil consumption on the first 1000 miles, no refill or changes or leaks.

Carb, intake and the clear hose off the PCV are still clean inside so I doubt that there was a lot of oil going this way. Anyway, I´ll build a baffle just to be safe.
I have the engine apart again, and it´s obvious that the motor has been run without oil. The oilpump was a new Melling HV, it still look ok, but the number 1 rod is blued at the bottom end and has the worst bearing, all other bearings are worn down to the copper layer.

I´ll make some interviews with some poeple and see what they have to say....
Thanks for your help, I´ll let you know!!!
Chris

 

Ok, well I had to learn this also(once upon a time[not too long]), but atleast my motor wasn't finished or in a car yet. I thank "Big Pauly" for that. I don't see any vents in the valve covers. If those are the ones he ran it with....It would all puke out of the fill tube breather. A 383 SBC isn't a stock 283 or even 350. There is some serious pressure in the crank case that releases up through the heads. I'd say....either get some valve covers w/openings for breathers, buy some old school breathers from someone here, or new old school type from MOON. Good Luck

 

I'd also like to add that it looks like the absolutely wrong intake for the motor.