Thread: really bad oil burning problem

Tweet

new to the site, like it alot! rebuilt a stock 283 twice, (to stock spec's). both times it burns oil, (first time, one qt per 80 miles, second time, one qt per 30 miles. first time had 550 miles on it, the second time has only 80 miles on it.) I'm down to one thing I did wrong, use white lithium grease on the rings, both times. (both times the engine was to be stored for a time) Is this a big boo boo, or will the grease eventually wear off? Prior to this I have always used oil on the rings. All sorces of oil coming from the top side have been eliminated per say. (intake, has no pcv valve- open system, valve guides etc.) All machine work and clearances check out. (the machinist is one of the best in town) First set of rings were Federal Mogul, the second was Hastings. (on the second set the block was "re-honed" to clean it up, not loosing much clearance, piston to bore is .002-.0025) The only other questionable item was the drain back holes behind the oil rings on the pistons. There are four of them, small ones, two above each skirt area. The stock piston had eight holes behind the oil rings. Could this be a problem? (though 3 piston companys say this isn't a problem.) If this isn't a problem, then I'm back to the grease issue. It has a stock oil pump and the Clevite bearings the second time around eliminated the "rod squirters" by not notching the bearings for it. Any help would be appreciated.

Not a good idea to eliminate the squirter grooves, SBC's eat cams quick enough with 'em!
The oil burner problem, wow, 30 miles to a quart, that's some serious consumption! Sure it's not leaking? It must smoke like a Bingo hall full of little old purple-haired ladies! Some thoughts...Manifold leak sucking oil from the valley, I had that problem on a 318.
Do a leakdown test, no special equipment needed, just thread an air hose fitting directly into the plug hole and listen for air leaks.
The grease thing, well, it isn't the best stuff for the job, but it shouldn't cause your problem unless it carbons up the rings on startup , that would have been obvious on teardown.
How does it run otherwise?

thanks for responding. I was led to believe the sqirters became not necessary later on is why they deleted them. If they are important in the early motors, I can always change that, for I feel I'm going to have to tear it down again. Engine doesn't drip a drop, and yes it smokes like crazy. Manifold gaskets are ok. I even pressurized the intake system on the car by making a plate over the carb opening with an air inlet, then backed off the rockers to the intake valves and added about 35-40 lbs of air. Took a coil bracket bolt out to put the stethoscope right into the lifter valley, checked for noises through the exh. crossover, and down the oil fill tube. No leaks, seals like an air tank. Also, the intake gaskets show to be crushed good and even. So I'm pretty sure I can eliminate the intake for now. Leak down test shows it to be by the rings. Compression is 160 lb perfect on all eight. Tear down showed no carbon or anything else foreign. It runs great! I can idle it down to 350 rpms and it runs steady and smooth. (that should also eliminate intake by means of a vacuum leak by the gaskets). Vacuum guage reads 17 in park, 14 in gear. It accelerates fine-it runs perfect per say. The cylinder heads were checked for cracks the first time, and pressure tested the second time. It has both the o-ring and umbrella seals. The second time the guides were rechecked too. (they are all new ones). The only original problem with the motor was excessive cylinder wear due to the car lived on gravel roads most of its life. The motor had 100,000 on it. It only had blow by out the road tube and breather cap, none out the exhaust before it was taken apart the first time. After 25 years, this ones got me over a barrel.

Flyin' by the seat of my britches, here - with all that you have said, I think I'd be looking real hard at the cylinders, pistons, and rings for fit, clearances, and roundness of the bores and pistons, or perhaps just one of them (?). Mic everything really well, double check end gaps and gap alignment, and only use oil on the cylinder walls and rings on assembly; the grease might not hurt anything, but, on the other hand, it might cause a problem. If you are going to store the engine, squirt some oil into the upper cylinders after you are done running it, and turn it over a couple of times real easy by hand to spread the oil around, and put the plugs back in and seal it up; it should be fine.

ring gaps in alignment? Rings installed up-side down?

Whatever the problem is, it should be obvious when you see it.

on the second rebuild we paid special attention to what rumbler and firebird suggested. My machinist double checked after re-honing for cylinder and piston roundness, then I rechecked again back at the shop. Those two items seem to be ok. I'm positive I put rings on right, followed ring instructions to the letter. Later on I spoke to Total Seal ring company and they asked me about all the specs on clearances, bore and hone job, etc. His response was "sounds like the clearances are ok." I also talked to 3 different piston companies to which one was the company of the pistons we have-Sterling-which is now owned by Federal Mogul. Same thing-sounds like all clearances are ok. You can see why I'm stumped on this problem. The only thing Total Seal could tell me was grease was a no no. Federal Mogul said it isn't the piston causing my problem, but something else. We'll go through everything again when we take it apart. This wouldn't be so bad if it was my car, but it's my bosses $30.000 '57 chevy he likes alot.
He's been real patient about this. He is a great boss. Thanks guys for trying to help me. any other thoughts, crazy or not let me know. When the problem is solved I will defenetly let you guys know! When time allows I'm going back through and seeing if I can help some of the other guys out. Some of their problems I've had in the past and would like to help like you guys have for me.

What do the spark plugs look like? All even or is one or two showing oil usage?

well, there round....just kidding. All the plugs have oil on them, both rebuilds. I've even asked if there is any way oil can get into the gas through the fuel pump, but not get in the oil, or leak outside of it. Everyone says that can't happen. Also, we should be able to see that in the glass fuel filter by the carb. Some have suggested too rich carb washing the cylinders, but the carb checks out fine by my carb guy and myself. No black smoke out the exhaust, just pure blue. (I don't have a gas sniffer to be 100% sure, but pretty sure that isn't it). By the way, the rings are iron rings and have been told they should seal right away, per say. (you may have a bit of light smoke or blow by for a little bit, but in general it shouldn't "smoke" like ours.) All other engines I've done didn't smoke like this. I've used iron and non crome molly rings in the past with no problems. (always used oil in the past on the rings). They say don't use synthetic oil on break in because it's too "smooth" and won't let the rings seat. That's why I come back to the grease issue, for it is defenetly "smooth". I did talk to Permatex, and they wouldn't tell me for one if their grease was ever designed for rings or not, and if they thought this would be a problem. They basically said they didn't know, in so many words. (or didn't want to admite to it?). Thanks again.

can't see the grease being the problem, although as the others say, I've always used oil... the grease could carbon up on the piston, but i just don't see it causing your problem.

I once heard of an engines mystery oil burn turning out to be a blown diaphram in the brake booster unit, and it was sucking out brake fluid...but that is obviously not your problem.

I'm assuming you have no blowby out the crankcase vent?(pcv)

well, speaking of PCV.. here is a longshot for ya... MAYBE you do have a crack on the bottom of the intake manifold, and the PCV is pulling down the pressure in the engine, and thus you are not seeing a vacuum leak. Try pulling out the PCV and plugging it off... see if you detect a vacuum leak then.

Sometimes it's something really dumb. A buddy changed intakes and made a real oilburner. Drove everybody nuts for days. Finally, I was checking his vacuum lines and guess what? He'd disconnected his oil guage and ran the oil line to a vacuum port! He's no dummy, just a temporary lapse, but shit happens!

well its the little things that can stump us everytime....well judging by your compression test and verifying 160 in all 8......thats an indication that rings are doing there job and sealing it up......Another area that may be looked at is are you running a pcv valve in the rocker covers.....it could be that the crankcase is building too much pressure and forcing oil past the rings and guides..........If you do have one maybe its not doing its job......another indication of this is that all the plugs are oil fouled.
thats why i suspect the motor is building too much crank case pressure......give that a shot and let us know what you find ans the solution...........that lithium grease will discipate with heat and engine oil........its also known as engine assembly lube.....I use it and have not experienced a problem with it....just make sure you change the filter after camshaft breakin cause it will plug the oil filter really quick.

I was just wondering if it is smoking when its cold too or just after it warms up. Might pull the valve covers and look over the valve seals. I had this problem one time and found that several of the seals were chewed to pieces somehow.

hey Firebird: ours doesn't have a pcv valve, has the road tube and breather cap on the oil fill tube. (both are clean and working) from the start I can't believe either the grease being a problem. R Pope: Bet that baby burned oil! (I'll admit I"ve had a few "dumb" things in the past I've done). 81 Cabellero: It would seem rings are seating by compression test. We're going to redo the leak down test to be sure. We did change oil right away after second rebuild, and for good measure put a few miles on and changed it again. Corvette64: Love that generation of vette's. It usually takes about 5-8 minutes to start smoking. One would hope this would eliminate the seals, but won't hurt to look at them again. (we're using o-rings and umbrella seals). We are considering pulling the intake and see if it is cracked somehow. I've been told on sand castings about sand shifting and could have a thin layer somewhere that cracked. One would think a crack would have to be in the right place (like the plenum) to get oil on both sides of the dual plane. If it was cracked only on one runner, one would thing it would affect 1-4 cylinders, but not all eight. There is a chance though it could "distribute" under the carb to crisscross to the other cylinders.

Not really, from my experience they tend to start leaking after the car is warm. Check the valve seals first. Its easier than tearing the intake out.

I love a good mystery , as frustrating as the things can sometimes be. Seems to me that everything has been covered, but you're unquestionably missing something - hiding in plain sight, quite possibly just a small detail that is getting overlooked. I'll be watching this thread for the conclusion.