Cat D4H loses power after 30 minutes

[SimpleFarmer]

My D4H Caterpillar runs great for about 30 minutes and then it begins to act like it is running out of fuel. The last time I tried to use it I let it run for one hour then started my work. 30 minutes later I had to shut it down because it was missing and would only run at 50% power or less. If the throttle was increased, it made no difference. No change in the engine sound. I have loosened the fuel linkage at the ?fuel distribution block? Before it goes to the cylinders and fuel is present, no air (my D4H does not have a hand pump to purge air and pressurize the fuel line). I have looked for a fuel filter but have not found one. I am looking for a filter about the size of a soup can, that is what is on my IH tractor.

Does anyone have some clue as to what is happening to my baby? Can there be water in the lines? Seems like that should keep it from running altogether. Thanks.

These are all the numbers that I have found.

Caterpillar D4H Dozer
1986?
Ser num. 8pb01884

45v66228

--------2431


Holt tag on back
W/O. 0115330
S/N. 1CE0236p

Caterpillar tag near seat
D4H
3204DI*8PB01884
45V66228
1CE02431

 

[Delmer]

Have you drained the bottom of the tank lately? Sometimes you'll have a petcock on the bottom of the fuel tank to drain off the water and dirt, if that's plugged up with dirt, then you have a good clue to what's going on.

Finding the fuel filter shouldn't be that hard, start at the tank and follow the line. Or start at the injection pump (might look like a fuel distribution block) and work back toward the tank. If the line goes directly to the tank, then it's a fuel return, not the line you're looking for. If it's not a familiar canister filter, then be careful taking it apart that you don't lose any pieces or put it back together wrong.

How long have you had this d4 and how long has it done this? Same with a full tank or half tank of fuel? Is there any suction on the fuel tank cap when you remove it when it stalls?

 

[Welder Dave]

Having went through this with a 3204 in 931B I believe your problem is a plugged strainer at the lift pump. It will cause the machine to only idle and eventually quit. There is a long hex fitting on the lift pump where the fuel line connects. Take this hex fitting off and there is a screen on the end that goes in the lift pump. The screen is removable using a hex key inside the hex fitting. I didn't quite understand what people were telling with mine and was really stumped until I finally realized where the screen was and how it comes out. I could run for about 30 minutes then only idle and then would quit altogether. I let it idle/sit for a few minutes and then could use it a bit more but the time would get less and less. It took me about an hour to move it an 1/8 of mile. I had to move it as the ground was soft and I didn't want it sink sitting overnight. It looked like shredded wood in the strainer.

 

[SimpleFarmer]

Thanks for all the info... I will look for a drain on my tank (I have never done that) and check the strainer on the lift pump. I will make an effort to find the fuel filter, I confess I haven't traced the lines yet. I'll report back.

 

[Welder Dave]

Check the strainer at the lift pump first. It gave me fits and did exactly what you are describing.

 

[Delmer]

Check the strainer at the lift pump first. It gave me fits and did exactly what you are describing.

Agreed. That's one of the most likely things to let it run that long and then plug, then let it run again. Please find the fuel filter too, and the tank drain.

 

[Mobiltech]

Filter is number 17 in this picture. You should be able to follow lines from pump.

 

[SimpleFarmer]

Filter is number 17 in this picture. You should be able to follow lines from pump.

That looks like the filter is on the left side of the engine, the opposite side of the lift pump.

 

[SimpleFarmer]

Agreed. That's one of the most likely things to let it run that long and then plug, then let it run again. Please find the fuel filter too, and the tank drain.

I took apart all the connections to my lift pump but I did not find a "screen" filter. I did drain some fuel from the tank and it did have some black garbage come out as well as some possible water. I started it up and it sounded real good, but that only lasted about ten minutes. So I'm back where I started. I drained some more fuel, but it looked good this time.

 

[Welder Dave]

Sorry, I can't post a pic. but there should be screen on the fuel line at the lift pump. My 931B is a 1986 as well. On mine it is a long hex fitting with a screen in it. The screen sticks out the one end but is removable to clean.

 

[SimpleFarmer]

Sorry, I can't post a pic. but there should be screen on the fuel line at the lift pump. My 931B is a 1986 as well. On mine it is a long hex fitting with a screen in it. The screen sticks out the one end but is removable to clean.

Here is my lift pump, back together.



I think I'm missing the screen. Must have come on the D4H-L, the luxury model.

I'm going to change the fuel filter next, since I had that mess come out of the tank.

 

[SimpleFarmer]

I think I've found my problem, thanks to you all. The fuel filter was about half full of water and garbage. I bought a NAPA Gold 3522 with a drain on the bottom. Hope I remember it's there. Next time, this will turn out differently.

 

[Welder Dave]

Here is my lift pump, back together.

View attachment 167482

I think I'm missing the screen. Must have come on the D4H-L, the luxury model.

I'm going to change the fuel filter next, since I had that mess come out of the tank.

Maybe it's in the elbow? On another forum was where someone with a D4H was explaining to me where the screen was and that it's not uncommon to become clogged. Where is the hard line to the injection pump coming from?

 

[Delmer]

You'll know soon enough if you have it fixed. Now drain a cup from the filter and the tank every time you use it, until it comes completely clean for many times in a row, then drain them every time you fill the tank.

I like to drain the filter when it's been run so it's warm and loosened up, and starts and runs easily, then rev it so it doesn't die as it's refilling the filter.

 

[DMiller]

If the fuel stays Black drain the fuel use it on brush piles, use a few fresh gallons to flush the tank out then put in clean new fuel WITH a algaecide in it. Black goopy crap is fuel born algae bloom and damned hard to get control of, fouls filters regularly and just nasty to get rid of.

 

[DavePat]

Hope this topic is not to old for me to post. Forgive me MODS, its my first post. I had / have the same problem as the OP. I have a D4H series 2, it doesn't get used much at all. I finally found the pre screen from the tank to pump. It was under the injector pump about 12 - 15" hidden by I don't know what. All I can say is take off the panels and look around. Follow the lines. I had an inch and a half of what looks to be diesel algae in the screen bowl, and the gravity line was just trickling fuel. So I cleand the screen, and bowl. And Slightly blew air back through the line to the tank. Then drained the line into a container, some chuncks of algae came out. gravity fuel flow seems good now. I also loosened that pre screen bowl until fuel came out so not to allow air into the system.

 

[DavePat]

I'm sure Ill have on going problems with this and many other issues. At least I know where that darn fuel pre screen is on a D4H, and hopefully this thread helps out more people. I guess now I should go introduce myself to this wonderful community. Thanks all.

 

[dennis sanders]

Just a possibilty...could have algae in the fuel line....i though the guy was joking until he showed me the algae treatment....

View attachment 167459

I took apart all the connections to my lift pump but I did not find a "screen" filter. I did drain some fuel from the tank and it did have some black garbage come out as well as some possible water. I started it up and it sounded real good, but that only lasted about ten minutes. So I'm back where I started. I drained some more fuel, but it looked good this time.

 

[dennis sanders]

A bit late...saw where Dmiller already mentioned this...

 

[nutwood]

If the machine is used infrequently, this problem will continue to haunt you. My solution has been to use fuel conditioner and fit an additional filter and trap in an easily accessible location that I can see whilst operating. Takes seconds to open the drain and drop out any crap that's found it's way into the system.