Runs nice and dies in 20 min UPDATE UPDATE

[Danica]

Since you mentioned using the tractor for bush hogging, is there any chance your rad is plugged with debris just enough to let you run for 10-20 minutes, depending on rpm, and then a temp sensor is shutting your tractor down, until it cools down enough to run again, for another 10-20 minutes ? I would remove rad, and give it a good external cleaning, between the fins. Seems like it is definitely high temp. related to me. It is definitely a good idea to change all fuel hoses, as others have mentioned, they do get old and break down, causing running issues.

OK! Excellent idea (other than the “removing” part. I could still shop vac the outside screen thoroughly which I will do after this air filter test which now sounds like a failure as it has been running nearly 20 min at 1,500rpm and I can hear it start to die down. Once it dies…or close to it… I will shop vac as much of the rad and fans as I can. It happens ALWAYS when temp hit the midway pony on the gauge (in cab).

Thanks for your ideas!

Danica

 

[Danica]

Well new air filter was promising at first as after 20 min rpm started dipping from 1,500 to 1,400 and this jumping goes down continued until could tell it would eventually die. It tried and tried to maintain 1,500rpm but the engine would slow down for a few secs then recover to 1,500. Eventually it couldn’t hit the initial 1,500 and the dipping process just continued until it was struggling to maintain 1,000.

So, fuel lines will all get changed out after I remove the sediment bowl and 2x check that everything is properly seated etc. thing is, I’ve pulled these lines during the final death throes and got a stead stream of diesel in from tank, out from filter housing, and out from the two low pressure outflow lines.

The saga continues…. Thank you all for your ideas.
Danica

 

[Raul-02]

I agree that is a possibility

It was an idea. You seem to have eliminated so many other possibilities.

 

[dirttoys]

Well new air filter was promising at first as after 20 min rpm started dipping from 1,500 to 1,400 and this jumping goes down continued until could tell it would eventually die. It tried and tried to maintain 1,500rpm but the engine would slow down for a few secs then recover to 1,500. Eventually it couldn’t hit the initial 1,500 and the dipping process just continued until it was struggling to maintain 1,000.

So, fuel lines will all get changed out after I remove the sediment bowl and 2x check that everything is properly seated etc. thing is, I’ve pulled these lines during the final death throes and got a stead stream of diesel in from tank, out from filter housing, and out from the two low pressure outflow lines.

The saga continues…. Thank you all for your ideas.
Danica

I will give you $7 to pull the thermostat and test without it

Just kidding (mostly) would sure love to hear if it matters?

Best,

ed

 

[piper184]

Danica,
You said that the problem starts as the temp reaches the mid-point on the temp gauge on the dash. Working on the assumption that the sender and gauge are correct, it is not likely that you have an overheating issue.
Before you get too far down the overheating rabbit hole, it might be best to get an infrared thermometer and check the temperatures externally. One with the little laser pointer is really handy to have if you don't have one already. Mine spends as much time in the kitchen as the shop. I should get another one.....

Just start the cooled off tractor and start taking readings at places like the head, the block, the thermostat housing, the upper and lower radiator hoses and the top of the radiator. This will give you a good indication of how the heat is moving through the system as it warms up. Diesels like to be warm so don't be alarmed if you see 195+F at the thermostat housing. As the coolant progresses through the radiator you should be able to see lower and lower temps until it gets back to the water pump.

If you don't see anything much over 200F by the time the tractor starts to sputter, you can be pretty sure it is not an overheat situation. One other place to check is the injection pump housing to see if it is overheating.

I would be leery of removing the thermostat unless you have a reason to do so. If you need to do a clean and flush of the system, by all means pop out the thermostat and check it in a pan of water on the stove with a good thermometer. You will be able to watch it open and close and observe the temps when it happens. I do this with new thermostats before I install them. You would be surprised at how often a new one is out of spec.

In my experience running an engine without a thermostat will most likely cause it to overheat. I have never tried it with a diesel, but I have seen several V8 gas engines overheat when the owner thought it was good idea to remove the thermostat "for better cooling". What actually happened was the coolant was flowing through the radiator so fast it didn't have time to cool down.

One last thought: I am not familiar with which injection pump is on your engine but I wonder if the governor is giving problems. If the governor is not lubricated by engine oil but rather has it's own sump it is possible that it needs attention. The Bosch like clone on my tractor has the governor and injection pump crankcase lubed by the same oil but it is separate from the engine oil. If it is not maintained, the governor can do all kinds of goofy things.

Sorry for throwing another "possibility" at you.

 

[DieselMonk]

Oh boy… what a thread this is… took me a while to read! First off, I am always careful with lift pumps. They can be intermittent, be it electrical or the pump. So, when the tractor dies you should hear the fuel lift pump still running until you turn the key off. Take off the fuel hose after the engine dies and make sure the pump keeps pumping fuel.
Next thing I’d recommend to do is to run the engine under a hard load instead measuring stuff at idle. Reasoning is that you can tell how much power you got at any given time. If you got full power at the beginning and later dies, rules out a lot of tiny problems. I assume that you can’t restart the tractor until it has cooled off?

 

[dirttoys]

Danica,
You said that the problem starts as the temp reaches the mid-point on the temp gauge on the dash. Working on the assumption that the sender and gauge are correct, it is not likely that you have an overheating issue.
Before you get too far down the overheating rabbit hole, it might be best to get an infrared thermometer and check the temperatures externally. One with the little laser pointer is really handy to have if you don't have one already. Mine spends as much time in the kitchen as the shop. I should get another one.....

Just start the cooled off tractor and start taking readings at places like the head, the block, the thermostat housing, the upper and lower radiator hoses and the top of the radiator. This will give you a good indication of how the heat is moving through the system as it warms up. Diesels like to be warm so don't be alarmed if you see 195+F at the thermostat housing. As the coolant progresses through the radiator you should be able to see lower and lower temps until it gets back to the water pump.

If you don't see anything much over 200F by the time the tractor starts to sputter, you can be pretty sure it is not an overheat situation. One other place to check is the injection pump housing to see if it is overheating.

I would be leery of removing the thermostat unless you have a reason to do so. If you need to do a clean and flush of the system, by all means pop out the thermostat and check it in a pan of water on the stove with a good thermometer. You will be able to watch it open and close and observe the temps when it happens. I do this with new thermostats before I install them. You would be surprised at how often a new one is out of spec.

In my experience running an engine without a thermostat will most likely cause it to overheat. I have never tried it with a diesel, but I have seen several V8 gas engines overheat when the owner thought it was good idea to remove the thermostat "for better cooling". What actually happened was the coolant was flowing through the radiator so fast it didn't have time to cool down.

One last thought: I am not familiar with which injection pump is on your engine but I wonder if the governor is giving problems. If the governor is not lubricated by engine oil but rather has it's own sump it is possible that it needs attention. The Bosch like clone on my tractor has the governor and injection pump crankcase lubed by the same oil but it is separate from the engine oil. If it is not maintained, the governor can do all kinds of goofy things.

Sorry for throwing another "possibility" at you.

I wouldn't run it all season without a t-stat. That said the risk is not reaching operating temp, not overheating. The water rushing through the engine at mach 1 and not cooling is a wives tale.

For the purpose of diagnostics, I think it is a great test, little time, no ir thermometer ,no cost, and no risk.

However, I am late to the thread, I am sure the op is tired of dealing with it, and may not want to do one more goofy thing to satisfy my curiosity



Best,

ed

 

[rScotty]

PS re your comment on fuel lines — why would it take 20 min and a warm engine for this problem to manifest itself? I mean, if there was air coming in are you suggesting that it takes a while for a sufficient ‘bubble’ in the line(s) to become a problem?

Tx again,
D

Yes, exactly that. And I wish I could provide a better mental model of how that a fuel line would do that - but I don't have one. Oh, I guess that forming a bubble could be due to small cracks in the hoses plus some running vibration over 20 minutes or so. And that may be as high a possibility as a subtle change in elasticity of the rubber hoses due to heat.

We keep going back to fuel because everything seems to point that way. And also because now that I see those hose conditions that's more evidence. THose hoses are terrible! It is time to replace regardless. That is a hazard.

It's not unusual at all to start in to fix a single problem and see some maintenance that needs attention.

Temperature related problems (usually) present differently. I have not had any luck with IR guns and temperature readings. There is just too much dependence on how different surfaces reflect IR.

But it can be both...or even electrical. I had one common rail diesel job that ran fine until it warmed up and then had no power. It turned out to be that the wires to the injectors had gotten hot at some time and partly burned where I couldn't see them. Result was high resistance to the injectors when the engine got hot... which lowered the signal voltage....and then the injection faltered. All temperature related, but it was sporatic. It didn't just gradually die as yours seems to be doing.

If I were a mechanic looking at that tractor at this point and having the info we have now, I would probably hang a bottle of diesel fuel from a ladder and run a line directly into the fuel pump. Not the lift pump - if it has one - but the fuel pump. The idea beng to take everything else out of the fuel feed system. Then start it up at medium high RPM and see if it dies.

If I was out in the field and this happened I would wait until it quit and then loosen a line at an injector until it just starts to leak some diesel out ....then go around and crank the starter while looking to see if I am getting a nice pulsating leak at the loose connection. If so that indicates diesel fuel getting to the injector.

Then I'd sit down and think for awhile..Might even post to TBN....

rScotty

 

[Danica]

I will give you $7 to pull the thermostat and test without it

Just kidding (mostly) would sure love to hear if it matters?

Best,

ed

Ed, I will give it a try! No need for the $7 as it barely buys a half gallon of milk these days!

 

[Danica]

Yes, exactly that. And I wish I could provide a better mental model of how that a fuel line would do that - but I don't have one. Oh, I guess that forming a bubble could be due to small cracks in the hoses plus some running vibration over 20 minutes or so. And that may be as high a possibility as a subtle change in elasticity of the rubber hoses due to heat.

We keep going back to fuel because everything seems to point that way. And also because now that I see those hose conditions that's more evidence. THose hoses are terrible! It is time to replace regardless. That is a hazard.

It's not unusual at all to start in to fix a single problem and see some maintenance that needs attention.

Temperature related problems (usually) present differently. I have not had any luck with IR guns and temperature readings. There is just too much dependence on how different surfaces reflect IR.

But it can be both...or even electrical. I had one common rail diesel job that ran fine until it warmed up and then had no power. It turned out to be that the wires to the injectors had gotten hot at some time and partly burned where I couldn't see them. Result was high resistance to the injectors when the engine got hot... which lowered the signal voltage....and then the injection faltered. All temperature related, but it was sporatic. It didn't just gradually die as yours seems to be doing.

If I were a mechanic looking at that tractor at this point and having the info we have now, I would probably hang a bottle of diesel fuel from a ladder and run a line directly into the fuel pump. Not the lift pump - if it has one - but the fuel pump. The idea beng to take everything else out of the fuel feed system. Then start it up at medium high RPM and see if it dies.

If I was out in the field and this happened I would wait until it quit and then loosen a line at an injector until it just starts to leak some diesel out ....then go around and crank the starter while looking to see if I am getting a nice pulsating leak at the loose connection. If so that indicates diesel fuel getting to the injector.

Then I'd sit down and think for awhile..Might even post to TBN....

rScotty

Thanks for the insights Scotty. Your reaction to the hoses clinches that decision. I will replace them all tomorrow. Regarding the temperature related source I’m leaning your direction because it so clearly a lack of fuel/combustion issue. I haven’t bled the injector because there is a set of four metal lines running right in front of them making wrench access virtually impossible. There is no lift pump on the pre-99 Shib engine I’ve concluded (vendors selling a lift pump for the ford 1920 specifically reference post-99 and mine was bought in Aug 99 so engine likely built in 98 or before).

I guess first thing tomorrow is replacing three lines (I cannot access the bottom of the fuel tank on this tractor even if I were an octopus).

Thank you for your advice and insights,
Danica