Overheating

A few weeks back I posted about no power under load and overheating. I found what may have been a restriction in fuel flow, and things seemed to improve - power wise - but I really have not put a strain on things to check that out.

But the overheating part, that is a different story. Was out yesterday pulling a finsh mower, nothing too heavy, and after about 1 hour, I had a boil over. I do think I had the radiator a little too full, but rather than having fluid come out the overflow tube, I had the full blown spew out the radiator cap eruption.

Soooo, today I go out and check and the rad is about a quart lower than it should be. I went ahead and drained rad... stuff coming out didn't look too bad.... then refilled with water, ran for a few minutes, and drained again. Did this a couple of times. Finally refilled to the correct level (just covering the tubes) and went out to mow again.

Seems like the same song, second verse. I was finish mowing - not cutting anything too heavy - and after about 1 hour(this is not a guess, I timed it) I could tell the tractor was starting to overheat again.... started running a little rough, lost a little power, and saw the oil pressure drop from its normal 30 -35 into the mid 20s. Shut down the finish mower and drove steaily back to the shop...about 3 minutes. Once there I shut it down and could hear the coolant "boiling" in the engine for a good 4 - 5 minutes, but never did get the volcano effect this time.... I think I would have if I had continued.

So, I will list what I have checked so far, but I seem to be out of ideas, and I KNOW someone here can point me in the right direction...

Compression - checked after warming up a few weeks back and had 120-120-90-90 - dry. Leaky head gasket? No visible oil in rad or water in oil. I did fill the rad all the way to the top and watched for bubbles.. none detected..... but the fluid does swirl quit a bit.. I guess the water pump is working.

Thermostat - don't have one... I replaced the rad hoses last year there wasn't one in to start with, none is there now.... unless foreign terrorists came and installed one in and evil plot to..... never mind.

Radiator - nice and clean - no crud build up front or back.

Fan - spins nicely, thank you, and I did snug up the belt just to be sure.

Other things checked dealing with the power issue -

Fuel flow - good - cleaned all the screen, filters, etc.

Sparkies - nice, strong and blue. Tractor nearly the first time it turns over.

So, what now? I seem stumped as to why I am overheating.... after an hour??

Ideas please... and thanks...

Odie1

• Hobby farm

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The most common reasons for overheating are debris in the radiator fins, overfilling the radiator, a slipping fan belt, low coolant, leaky or bad water pump, clogged radiator, stuck thermostat, clogged water jacket & no fan shroud. Other less common causes are timing, mixture & a blown head gasket. I'd suspect something real simple.....like debris or overfilling or a combination of the two.

Am I misguided? (At least on this issue...)

Bill

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A cool running engine is going to create engine wear problems.

I think I recall how to set the main jet, and believe I have, but will recheck.

I guess I have never known how to check to see if the advance is working on the dist.

Once I have the dist. off the tractor and in my hand, what should one do?

Thanks again
Odie