165 perkins gas late model oil burner

I have a late model about 1973 Massey 165 with a Perkins 212 gas engine in it. It burns an incredible amount of oil in a very short time, except, and get this, it may be a clue to the problem, sometimes it burns no oil at all.

If I keep the RPM low it seems to not burn oil, if I run it hard, it uses about 2 quarts per hour. I have done a compression check and all cylinders are 130/140 PSI. It is not a calibrated gage, but it seems like great compression.

It also has all the power I could hope for until the plugs foul. It fouls the front three plugs slightly more than the back, but they all foul.

I just got it this spring with the dream of having a real tractor, I own two Fords, but wanted more HP for my little 40 acre farm.

Some history on the tractor: It was probably not run often for some time before I got it (Craigslist) and my first thought is the oil control rings being stuck , but I recently changed oil and filter, involving removing quite a bit of sludge from the filter can and replacing the paper filter.

As soon as I started it after the de-sludge/oil/filter change it burned no oil and ran great. This lasted about half an hour until it started spewing smoke again. I tried a motor flush, cylinder fogging, adding different solutions with the idea of loosening the lower oil control rings. Changing oil until it is as pretty as honey, but if I hit the throttle, it blasts blue smoke, and consumes oil like wild.

It has a red painted head, I am guessing rebuilt, but only guessing. It feels to me like if I can keep the oil pressure lower, it does not burn as much. The oil pressure gage is almost pegged high, it could be that I need to change the filter again after flushing, changing, flushing changing.

Is a filter restriction from moving years of debris a possible cause of high pressure? Could the valve train not being able to drain back cause guides or seals to be flooded and leaking past?

I am about ready to pull the head and inspect the guides and seals for issues. I hope that if I get the head off, the problem will be exposed.

I plan to get it right and own it until I die, if I can find the problem and get replacement parts for it, I will do it.

If anyone has seen anything like what I describe, I would be grateful for any advice on what to look for.

My dream is that someone will tell me to check some minor issue, (like a PCV valve) I will find the problem and not have to dig into this beast blindly. If it sounds like bad news I still need to hear it.

Thanks for any advice you may have.

Change the filter again and check the crankcase vent.

Check the back side of the carb air hose to see if it's split open, letting dust in. Had the same tractor years ago that the hose cracked open, letting unfiltered air in, wearing out the sleeves and rings. Hose was hard rubber with no braid support, and air pipe stress caused the hose to fail on the backside where it could not be seen. Tractor was just out of warranty with 400 hours when it happened.

Maybe the oil pressure relief valve is jammed, causing excessive pressure, if there was that much crud in the oil? Just a thought.

I have another filter on the way and will change it as soon as it arrives Monday.

No one stocks it local that I found. I had no idea that this model/engine configuration was uncommon, but it must be. I rebuilt the carb and inspects the boot while doing it. I think that if the engine had been worn out by an abrasive leaking, the compression would be low, or at least it would not stop burning sometimes.

I will look into the pressure relief and PCV valve also.

Thanks to those who read my post, it is longer than most, wanted to cover as much as I could.

Ken