I have a l4200 diesel tractor. I recently bought a 78” woodsmaxx flail mower and have been happy with the performance until recently. I’m engaging the pto at a low rpm then revving up to about 50% or 75% throttle. Everything seems to be working fine for a few minutes, then the engine stalls as if I’m running out of gas. It’s slowly winding down. After stalling it become very difficult to restart the engine, but after 10-20 tries the engine starts and quickly runs very well. If I don’t use the pto it doesn’t stall. It’s possible my old engine doesn’t have enough power for this implement, but I don’t understand why I can’t easily restart it with the tractor in neutral and the pto off. Is this just a fuel problem?
Diesel engine stalling with pto flail mower
- Thread starter Echo_Orchard
- Start date
Update. After looking closely at the fuel filter, I believe I have a lot of rust in my fuel tank. I guess my question now is, why would the tractor operate fine at low speeds, but stall at high rpms? Now have to decide if I want to spend $500+ on a new tank or try a rust treatment first. Any advice would be great.
North Idaho Wolfman
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Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
The rust normally doesn't come from the tank (most newer models the tanks are plastic), it comes from the fuel sending unit.
check that.
Flush the tank out and clean the intake pipe to the fuel filter as rust will clog up the inlet pipe.
check that.
Flush the tank out and clean the intake pipe to the fuel filter as rust will clog up the inlet pipe.
Your tractor is most likely losing power due to fuel starvation. If you get good fuel to the engine in adequate quantity your problem should disappear. The Wolfman gave you the fix for that.
Thanks for the help. I’m currently removing the tank to treat it for rust. It’s a mid 90’s tractor so does have a metal tank
Russell King
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L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
You will need to replace fuel filter of course and clean fuel lines or just replace them. But that is pretty obvious already, just had not been stated.
Diesel engine speed is controlled by the amount of fuel delivered.
I'd suggest pulling the tank and giving it and all your fuel lines a good clean, rinse the bowl and replace the fuel filter. Hose is cheap, you could just as easily replace the fuel line instead of trying to clean it. A lot of moisture, rust and sediment comes from fuel storage tanks. Make sure you clean and refill with good, clean diesel. Try to keep the fuel tank full in cold weather to minimize condensation.
I wouldn't replace the tank unless you had major rust flaking inside and tank leakage. After 30 years you probably have a lot of accumulated crud inside the tank.
That's easy. The engine needs more fuel at higher RPM. If the flow is restricted, the engine will starve for fuel a lot sooner at high load/ high RPM than if it's just idling along.
There are a lot of epoxy based fuel tank liners with good track record. I'd sure do that before I spent $500 on a tank. I assume that includes labor? I can't imagine paying $500 for just the tank.
Yep. Actually, it would probably be a lot easier. Cleaning the inside of a fuel hose is quite a challenge.
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Well, I hate to admit it, but I think I just had a bad fuel filter or fuel filter install. I ordered a new filter, as well as two new O-rings and the spring that goes in the bottom of the cup. Everything seems to be running fine now. Thank you for the help.