460 Help

[playfarmer]

My project is a 66 F100 that I installed a 460 in that was supposed to have been rebuilt about 5000 miles back. The donor truck (76 F350) sat for probably 4 or 5 years before I got it. Before I put it in I done a compression check and came up with good and consentant numbers about 125. Every since installed the engine is using lots of oil 1.5 to 2 quarts in 200 miles. So far I have about 500 miles on it since installed in the 66. The engine doesn't really smoke much if any at all and runs real well. No external leaks at all. Umbrella seals look pliable and good. It is just one cylinder (#2) the other 7 are nice and white that is turning the plug dark so where is all the oil going? Any guidance would be appreciated!!!!!!!!! Thanks playfarmer

[MadMaxetc]

If it's not on the floor, it is going out the tail pipe.

I had a rear main seal on a 302 that would only leek above 2500rpm. You might try holding the engine at a high rev and checking for leeks.

[William-in-St George]

Stuck rings from sitting? Check the torque on the intake gasket. And, go here....460forddotcomm. More info than you will ever need on these 460's. IMHO!

[Limestone66]

Compression ratio per cylinder seems good. Compression rings are fine, but you may have some bad valve seals as well as the oil control ring in the number 2 cylinder. I'd opt for a head job or just replace the valve seals. Is there any oil collecting inside the plug? If not, oil is leaking past the seals and blowing out thru the exhaust pipe. Just my

[donald luster]

Check with outboard motor dealers. The Evenrude motors has a very good solution that will unfreeze the stuck rings, They came out with because the gas is causing the ring to freeze up during the winter. Sometime I use pb blaster and squirt it in the cylinders overnight and then turn it over several time with starting the next morning. Sometime it will work.

[playfarmer]

The plug is a little oily and there looks to be oil on top of the piston. All of the other cylinders are dry and the plugs look good (burning white). What I don't understand is nothing looks that bad for the amount of oil that is being lost. This thing runs great and really isn't smoking very much. Any chance if it is a stuck oil ring that it will free up or am I just dreaming? Thanks for your comments!!!!!!!!!playfarmer

[playfarmer]

Donald I just seen your post. With the pb blaster did you start the engine with it in there or push it out and then start it? thanks for the postplayfarmer

[Limestone66]

Playfarmer; You could try the blaster on number 2 and let sit overnite, but i highly doubt it will fix the problem. You have a bad oil ring and it will only get worse over time and much use. Not trying to be a bearer of bad news, but facts are facts my freind. Still dont compensate for the amount of oil its using, unless the rear main oil seal is also defective. Check and re check under the bellhousing for oil residue. Still clean? Then baby the old girl for awhile until you can tear it down with a new set of rings. Its not as bad as it seems cuz it runs good, as you mentioned. You could change the oil and add a quart of MMO {Marvel Mystery Oil}. That could help it as well. Good luck with this.

[Toyz]

You might try removing the positive crankcase valve from the valve cover, rattle it to be sure it's free, check for vacuum at the hose, plug the valve back in the hose, but not the cover, and check for excessive blowby on a fully warmed engine. This would most likely NOT cause heavy consumption on only one cylinder, but the others may not be showing ready evidence yet. If the system is operating incorrectly, new hose, new PCV, and cleaned vacuum port is an easy fix.
Borescopes have become quite inexpensive, and some commercial rental places rent them to consumers. Might be worth the effort to obtain one and try to check the cylinder wall for marking indicative of broken rings. A cylinder leakdown test might also be revealing. That amount of oil consumption; if determined to be isolated to one cylinder would make me avoid driving the truck to limit damage. A broken ring land or other piston damage would be a likely culprit, which might have been in conjunction with damaged bearings allowing an overabundance of oil in that cylinder.
Gasket sets are expensive, but avoiding more damage may require pulling that head and the oil pan for closer examination. A failed bearing (or bearings), including cam, could also contribute to oil consumption issues, but would likely also affect the opposing cylinder somewhat.
Valves and guides have been mentioned; a defective oil pump is a possiblity, but also would normally affect all cylinders.
More than likely, you will find the majority of the problem at the #2 cylinder, whether intake manifold or gasket, piston/ring damage, cylinder damage ( wristpin, piston or ring failure), lower end bearing problems, or a combination of some of the items.
Be sure to check the simple things such as proper oil level.
Sorry to be so lengthy, but all these items need to be thoroughly diagnosed, IMO.
Paul

[playfarmer]

Thanks Guys I'll try the pb blaster and mmo. Don't really expect any miracles but worth a try. If this engine is trash has anybody had any luck with crate motors? Thanks again playfarmer

[62galxe]

A bad intake gasket can suck oil out of the valley.

[Toyz]

A bad intake gasket can suck oil out of the valley.

Not always the fault of the gasket; This is often incorrect matching between manifold and head, not uncommon on rebuilt engines.
Some gaskets are more "conforming" than others.
"Fixes" in a can or bottle may offer some relief; with the stated amount of oil consumption; I'm not certain I would allow the engine to run long enough to determine results. If the PCV proves to be working, and no excessive blowby from the valve cover is noted, oil level is correct, and fuel pump is not leaking, it's time to at least pull the intake, again IMO. A slightly scuffed cylinder wall can be cleaned up, a deeply scored one is another matter, same with failing bearings. I have had excellent luck with Ford factory rebuilt crate motors years ago; I have no personal knowledge of the Ford Racing or others. Again, 460ford.com has lots of info.
Paul

[R Pope]

I would pull the intake and reseal it. Check the old gaskets for leakage. Might be a cheap fix.