Engine burns alot of oil but runs great

[fftoddster]

I have a '37 Tudor with the 21 stud 221. Car had sat for 35 + years

Got it running and eng runs good but smokes and burns ALOT of oil (maybe a quart every 10-20 miles. I have tried MMO and NOSMOKE still smokes. Debating trying Bonami trick?
Compression 80 80 80 87 87 87 90 83
oil pressure dash gauge shows 50 cold 20 hot. I hooked up a maual gauge and showed about 25 and 5 hot at idle goes up with rpm.

I have read to run it and see if it gets better... BUT that's ALOT of oil and smoke.

Thoughts?

[flatheadmurre]

If that engine was ovehauled a few times with new rings the valveguides may be real worn...and then the engine starts and runs fine but uses oil.
Running abrasives through an engine is never a good thing...

[alanwoodieman]

best guess is rings are stuck- with the oil control rings being the worst---try to find some "ring free" made by bardahl, there are several other like products out there. is that compression with engine hot, all plugs out and throttle wide open? put a little oil in the cylinder you are checking and see if the compression goes up. another trick is to blow air into cylinder and listen for air escaping thru the fill hole but I doubt that will happen.

[fftoddster]

yes compression was on warm engine with all plugs removed and throttle open

[Jack E/NJ]

How much MMO? 10-20% is fine. Don't do anything drastic. Keep running it. Jack E/NJ

[fftoddster]

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I had poured 1 qt into all the spark plug holes and let it sit days and then rotated engine put plugs in and ran. so basically 1 qt in crankcase. Should I also pour into gas tank?

[J Franklin]

Gopher control!

[Jack E/NJ]

20% MMO mix directly into the crankcase. A quart MMO in a full gas tank can't hurt either. Jack E/NJ

[J Franklin]

Originally Posted by flatheadmurre

If that engine was ovehauled a few times with new rings the valveguides may be real worn...and then the engine starts and runs fine but uses oil.
Running abrasives through an engine is never a good thing...

See what a leak down test shows you. Sometimes a re-ring job makes the oil pull through the guides

[Bill OH]

Change oil and put in detergent oil. I had that with a 221 that smoked and detergent oil cured the problem. One quart of MMO in the crankcase would help. Be patient.

[fftoddster]

if I am not mistaken if the valves are sealing good on the valve seats then no air would blow past so would not get to valve guides. I see how a leakdown test shows where you are loosing compression ie either rings or intake or exhaust valves but I do not see how it would help to show where oil is coming from.

With valves in block like the flathead wouldn't oil have to go up hill past valve guides to get into combustion chamber Vs overhead valve engines. Is oil getting past valve guides a real likely hood?

[Jack E/NJ]

>>>Is oil getting past valve guides a real likely hood?>>>


IMO not likely. MMO is sold in gallon cans too. 8^) Jack E/NJ

[drolston]

Originally Posted by fftoddster

if I am not mistaken if the valves are sealing good on the valve seats then no air would blow past so would not get to valve guides. I see how a leakdown test shows where you are loosing compression ie either rings or intake or exhaust valves but I do not see how it would help to show where oil is coming from.

With valves in block like the flathead wouldn't oil have to go up hill past valve guides to get into combustion chamber Vs overhead valve engines. Is oil getting past valve guides a real likely hood?

Oil will run up that intake valve hill because of the vacuum. If it smokes worst on acceleration it is probably mostly rings. If it smokes bad when decelerating, it is probably valve guides.

[supereal]

Having sat for 35+ years, it is doubtful additives will do much more than allow the usual sludge that looks like "black Jello" in the valve chamber and the bottom of the oil pan to be circulated, clogging the oil galleries and the oil pump pickup. If the engine seems sound otherwise, a disassembly, clean out and inspection will hopefully save the engine. That isn't cheap, but trying to find a replacement engine today is much worse.

[Shu47]

If you can stand the smoke for a little while then I would try to run it and see if it gets better. If it does not get better then you will have to start tearing it down.

[cas3]

there are people driving around with lower compression than you and no smoke. wonder if the breather tube is plugged, or some other reason for pumping oil out. real motor guys?

[fftoddster]

Smokes good on acceleration and deceleration both sides as I have dual exhaust.

Can't believe the plugs look pretty good and dry for how much oil is burning.

[Tinker]

What color is the smoke?

[big job]

Then it must be smoking blow by at the oil filler.

[37 Cab]

A quart every 10-20 miles and the plugs look good? Something is amiss here. How long have you driven it? Exhaust pipe should be wet inside using that much oil.