2008 TC40DA loosing power

[Fields_mj]

I picked up a 2008 TC40DA in Jan to replace my old Ford 1710. Time will tell, but I'm pretty sure it's going to be some of the best money I've ever spent. That said, I do have one issue with it. After its been running for a while (30min to an hour), it acts like its starving for fuel, or developed an air leak. It looses power, and after several seconds, it dies. It will start right back up, but then does it again within a few minutes. The more I keep going, the more quickly it happens. After 4 trys, it's almost instant. If I walk away for a while (30 min), it will run for another 10 or 15 min before the problem comes back. I first noticed it this spring, but it wasn't as frequent. AFTER the problem started, I had some work done to it at a dealership which included replacing some leaking fuel lines. Problem seems worse after that, but I didn't have a lot of time on it prior so its hard to say.

I thought it acted like a clogged fuel filter, so I swapped that out last week and the problem still exists. I do notice that when the machine is running, the fuel bowl on the filter has about an inch of air at the top, but I can't see the fuel bowl from inside the cab (LOVE having a cab with AC), and by the time I get out of the machine after it dies, the bowl is full of fuel again. I'm normally running the machine in the back yard moving logs or totes of firewood, and I'm normally not running over 1500 rpm, often lower. My thinking is that either I have a lift pump that is weak, or I have air in the line prior to the fuel filter and its eventually getting to the fuel pump and injectors. Problem with that is that I'd think that it would pretty quickly work its way out and back through the return line.

Any thoughts or ideas?

Thanks,
Mark

 

[nyone]

Could be some junk in the tank clogging the outlet. Next time it's happening instantly take off the fuel line right below the tank and let her drip for a bit. Low flow there and it dosnt matter how good the rest of the system is.

 

[WM75Guy]

Sounds like an issue where fuel is getting choked off from the tank. After it sits enough fuel flows through to let it run for a little longer. From the tank to the fuel filter, the clear bowl, is gravity fed. Coming out of the bottom of the tank is a pretty small elbow, doesn't take much crud to block it. If that is the case that involves removing the tank and cleaning it out. Also, though uncommon, the cap may not be venting so you get a vacuum in the tank. Easy to test that, trying running it with the cap loose or off while sitting still and see if it stops.

 

[Fields_mj]

I think I had tried running it without the lid on at one point, but can't recall now. I've been worried that there might be junk in the tank or in a fuel line, but it seems like the issue would be more sporadic if it was something in the tank. If its stuck in the drain or elbow, that could explain it. I'm pretty sure the dealership replaced that fuel line, so I'd be a little surprised if there was something in it. That doesn't mean they did anything with the elbow though so its still worth checking. I also wasn't sure if there was anything between the tank and the fuel filter. Glad to know that there's not.

When the machine is running, should the bowl on the filter always be full of fuel? If so, that will be a pretty obvious way for me to confirm the fix because the air appears in the bowl almost instantly when I start the machine. Unless the o-ring on the bowl is leaking some air, I don't understand how that air gets in there.

 

[RobertN]

Sounds like might have fuel supply issues. If the fuel bowl isn't full, then pull the line and run to a clean container. Do you get good flow, not gunk? Check the fuel cap too; it might not be venting correctly.

Even when I change filters, if I don't get the air out completely, it only takes a minute to clear up.

Betting it is the vent, or you have some gunk blocking the hose /elbow where it goes in the tank.

 

[Fields_mj]

If its not normal to have air in the fuel filter bowl, then it sure seems like it has to be the vent or a restriction in the fuel line. I believe that fuel line was replaced by the dealership, but that doesn't mean that it didn't have an obstruction in it, or they didn't get it pinched or something. I suppose it could be that the line is laying such that it captured a large amount of air that won't bleed out, but that seems unlikely and it should be pretty easy to address that issue.

 

[Harry in Ky]

If its not normal to have air in the fuel filter bowl, then it sure seems like it has to be the vent or a restriction in the fuel line. I believe that fuel line was replaced by the dealership, but that doesn't mean that it didn't have an obstruction in it, or they didn't get it pinched or something. I suppose it could be that the line is laying such that it captured a large amount of air that won't bleed out, but that seems unlikely and it should be pretty easy to address that issue.

Fuel Filter | New Holland Agriculture | MyCNH US Store

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Look at return line (item #14) on this diagram. If you have that line on your tractor, then try this next time you put it to work. Pinch the line flat with washers and vise grips or something. Seal the line off and run it like that for an hour and see if the problem goes away.

When ever I find a similar problem on a tractor with that line I snip the line a few inches from each end and plug the stub with a rod, screw, bolt, anything to seal it off. Most engines seem to run better without that line in place. Particularly so if the filter won't stay full.

 

[dieselscout80]

The line on the top of the fuel filter is allowing air to be sucked in to the filter bowl see the below thread for details. I capped mine off and no issues since then.

New Holland TC45D won't start fuel supply issue

Does it just bolt in? It is next in line after the bowl. I was afraid to take it out.

www.tractorbynet.com

 

[Fields_mj]

Isn't that the return line? I've never had any issues with the return lines on any of my other diesel engines. Seems like capping it off would be hard on the fuel pump and make it more difficult to blead air out after doing any work on the fuel system.

 

[Fields_mj]

Looked up the fuel system in my service manual and found this. Looks like that line tees into the return line that runs from the injectors to the tank so capping it off shouldn't create any other problems. It makes sense that this would be causing me problems. The machine has spent its life outdoors, and a lot of the rubber is getting dried out. The dealership I bought it from replaced what they thought was needed before selling it, and the dealership that worked on it last month replaced the majority of what they could find, but there's always going to be something that gets missed.

I may also try running it up to full throttle next time it stumbles and see what happens. In theory, if there are no blockages, I would think that it should bleed any air out of the system.