Ford 8000 overheat

[gofarm]

I am asking for some troubleshooting help on a perplexing Ford 8000 overheat. I was driving the tractor from a distant field yesterday when it began to knock. As I pulled into my farm and let off the throttle, the engine quit. I tried to restart but the starter labored. I assumed two separate problems: clogged injectors and failed cooling system. The engine started up after it cooled off.

I cleaned the injectors and that problem appears to be solved. I took the tractor to another field today after idling for a while to finish the injector cleaning problem. At the field the tractor died as soon as I put it under load and I experienced the same labored starter issue. I came back after lunch and it started right up. In both overheat cases, the radiator did not overflow and both the inlet and outlet hoses were very firm (under pressure).

I just finished flushing the radiator. I noticed the pump is moving a reasonable volume but not at much pressure at about 1400 rpm. I pulled the belt off the pump and it turns freely and seems to move fluid. Thermo is not stuck closed. At this point my questions are: what are the possible failure modes for the centrifugal pump? Can it fail to a low pressure state without a leak? Are there other troubleshooting steps I should try? Why would the radiator not overflow? Thanks for any help you can offer.

[RickB]

What makes you think it is overheating? Sounds more to me like a lubrication/bearing/crankshaft problem, or a battery/resistance/starter issue. Unless you are making steam/blowing coolant/recording high temperatures with a known thermometer or other device, it ain't running hot.

[gofarm]

What makes you think it is overheating? Sounds more to me like a lubrication/bearing/crankshaft problem, or a battery/resistance/starter issue. Unless you are making steam/blowing coolant/recording high temperatures with a known thermometer or other device, it ain't running hot.

Thanks Rick. That is a good point. The reason I assume overheat is the way it behaves, especially that it will begin to lose power before it quits but will start again with no problem once it cools down 15-20 min later. Oil is flowing and shows no sign of burning. Top end is definitely getting sufficient oil, not sure on the bottom end, though I believe that is splash lubricated anyway. I just changed the oil/filter two weeks ago and the oil level is just below full. There is some metal in the oil but I believe that is simply particles that were stirred up from the oil change.

[whodat526]

sounds like you could have overheated it and now a bearing is trying to stack once it warms up and is put under a low i have seen it happen more than once

[gofarm]

sounds like you could have overheated it and now a bearing is trying to stack once it warms up and is put under a low i have seen it happen more than once

Distinct possibility. The engine was knocking from a clogged injector the way back from the first field. I slowed down but kept on for another 10 min. I suppose the force from that could have damaged a bearing. I'll have to check the filter for big metal.

[RickB]

Thanks Rick. That is a good point. The reason I assume overheat is the way it behaves, especially that it will begin to lose power before it quits but will start again with no problem once it cools down 15-20 min later. Oil is flowing and shows no sign of burning. Top end is definitely getting sufficient oil, not sure on the bottom end, though I believe that is splash lubricated anyway. I just changed the oil/filter two weeks ago and the oil level is just below full. There is some metal in the oil but I believe that is simply particles that were stirred up from the oil change.

Splash luubricated? Surely you aren't serious. Get somebody involved that knows these engines FAR better than you do.

[gofarm]

Splash luubricated? Surely you aren't serious. Get somebody involved that knows these engines FAR better than you do.

I thought that was the purpose of asking questions here. It would be wonderful if someone locally could take time out of winter planting prep to help me learn but that isn't possible. Absent that, I'm trying to learn this engine on my own by asking questions and tearing into it.

[gofarm]

Rick,

Do you know the oil system well? I pulled the valve cover the other day and noticed that oil was pouring out of the cyl 5 lifter and the head bolt for the rocker arm support next to it at a very high rate. The head bolt washer was malformed and I sealed it but the lifter continued to pour out oil, much higher volume than any of the others. I am just wondering if each cylinder has a separate oil path and if a lot of oil coming out the lifter means inadequate oil at the camshaft for that cylinder.

[RickB]

I thought that was the purpose of asking questions here. It would be wonderful if someone locally could take time out of winter planting prep to help me learn but that isn't possible. Absent that, I'm trying to learn this engine on my own by asking questions and tearing into it.

You would learn more by buying a repair manual than flying blind.
Choose Items

[gofarm]

You would learn more by buying a repair manual than flying blind.
Choose Items

Thanks for the link. I had checked the NH website for tech data but never found the site you sent. Very helpful. I have the I&T shop manual but it is worthless for understanding how the systems work.