M9540 Bogging Down

[TexasBest]

Gentlemen, I have a '12 M9540 with 128 hours, had it recently serviced, been an awesome tractor. I pull a 10' Woods shredder and the other day I was mowing some not too high grass and the tractor started bogging down, went from 540 down to 450 or so (don't recall the RPM), then it would get its balls back and run ok for a few minutes and then the same deal, took forever to finish mowing.

I blew out the air filter, checked everything all was good. Drove it in high gear down the road wide open at 22mph without the PTO engaged and it would run smooth for 30 seconds and then bog down and almost die, but would then run great again after 30 seconds or so, it's very intermittent.
Replaced both fuel filters, same deal, can't figure it out, it bogs down with or without the PTO engaged. The fuel filter swap didn't change anything.

Wondering if anyone had any ideas, hate to take it to the shop if it's something I can fix.
Thanks...

 

[piller]

What you are descibing sounds very similar to something that happened with my M8540, check to see if perhaps you have a pinched fuel line.

 

[Tx Jim]

Check to be sure fuel tank vents aren't plugged.

 

[farmer2009]

How fresh is the fuel? Is there any additives in it? If not try treating the fuel and checking fuel lines and connections. Also make sure tank is clean.

I know this new fuel has been hard on New Hollands this size. Mainly injector pumps. The local mechanics are saying to add motor oil to your fuel.

 

[TexasBest]

Thanks for the responses, couldn't find any kinks in the fuel line, the diesel is clean and not sure where the fuel tank vents are, but today when it started its bogging down I removed the fuel cap and it didn't change anything.
Wondering if it could be a faulty injector pump? It's really intermittent, today I mowed for 15 minutes before it started bogging down and then it did it every five minutes or so. I discovered that when I put the tractor in neutral the RPMs would get back to 2200, I'm at a loss?!

 

[TexasBest]

Thanks for the responses, couldn't find any kinks in the fuel line, the diesel is clean and not sure where the fuel tank vents are, but today when it started its bogging down I removed the fuel cap and it didn't change anything.
Wondering if it could be a faulty injector pump? It's really intermittent, today I mowed for 15 minutes before it started bogging down and then it did it every five minutes or so. I discovered that when I put the tractor in neutral the RPMs would get back to 2200, I'm at a loss?!

 

[stoyan79]

Bad fuel. Replace the fuel. It happened to me this summer. Gas station sold me bad fuel.

 

[farmer2009]

Bad fuel. Replace the fuel. It happened to me this summer. Gas station sold me bad fuel.

Possible. Also replace any rubber fuel lines. They can pass a visual inspection but be collapsing on the inside. Sometimes you can find the separation by finding a soft spot in the line cut it open and the inside layer has separated from the reinforcing layers.

 

[dixiedrifter]

Take off your fuel water separator bowl housing (the part where the fuel shutoff valve is) and clean out the housing where the fuel goes in. What happens is occasionally trash will get caught up in the narrow entry way before the shutoff valve and stave the engine for fuel.

 

[Tx Jim]

Take off your fuel water separator bowl housing (the part where the fuel shutoff valve is) and clean out the housing where the fuel goes in. What happens is occasionally trash will get caught up in the narrow entry way before the shutoff valve and stave the engine for fuel.

Had the same thing you're referring to happen on a M4900 water separator valve.