4035 HST will not increase RPM over idle

[SS454]

Hi all,

I have a 2010 Mahindra 4035 HST with a little over 200hrs that has been a great tractor other than replacing the typical problematic leaking fuel lines and a faulty PTO switch. This brings me to the first major issue. The Tractor sat over the winter in my shop and I had to contend with a dead battery but got that charged and it fired up with a little bit of cranking. The tractor eventually cleaned up and idled great but when i moved the accelerator lever to increase RPM it wouldn't increase more than 100rpm. I initially assumed maybe a linkage was stuck so I pulled the column cover and popped the hood to confirm that the arm on the FIP was moving. It eventually started running rough and would hardly start so i started wondering if the last time I filled my diesel jug and put it in the tractor that maybe I got some bad fuel.

I've since changed the fuel filter, drained and flushed the fuel tank (fuel did appear bad, smelled like paint thinner), and flushed all the fuel lines out. The tractor now starts and idles great again but still will not increase more than 100RPM. I'm at a total loss now, It doesn't appear that this is an issue anyone's had before from all the searches I've done. I'm reaching out to see if there's anything anything else I should consider before calling around and seeing if any local shops will look at it. Our nearest mahindra dealer was bought out a few years ago and no longer carries the mahindra brand, there isn't a mahindra dealer within 200 miles now.

It's almost acting like it's flowing through an orifice. I'm wondering if something in the FIP is gummed up or stuck? Possibly failed KSB or stuck shut off solenoid?

I appreciate any ideas anyone can throw out!

thanks,

Mason

 

[thepumpguysc]

The innards of the fip are gummed up..
Run some inj cleaner and/or SeaFoam thru it before condemning it..

 

[seville009]

Maybe I missed it in your post, but check your air filter - make sure rodents didn’t build a nest in it over the winter and clog it up.

 

[SS454]

Sorry, should have mentioned fresh inner and outer air filter. Old outer was dirty but no rodents or damage.

 

[Joe Hickerson]

Reaching for the stars here as I have an eMax, but I had the same "idle only" situation. Discovered a broken/bad fan belt and caused the ECU to hold at idle rpm.

 

[SS454]

Well, pulled fuel tank and discovered black sticky goo in the tank and lines. I assume it’s from breaking down of old ULS diesel. The stuff on the towel is from the return line in the tank which means it’s all inside the FIP and injectors. We run the FIP intake into a bucket of fresh fuel and it still would not rev. I guess to the dealer it goes.

 

[2TMike]

Hey SS454, I'm just seeing your post, and I realize you posted this a several months ago and may not be checking regularly since then. Quick questions: How difficult was it for you to get to the fuel tank to remove it? did you have to remove the floorboard? Any tips you could offer?

I need to replace fuel lines on my 4035, and it's a tight space between the floorboard and where the fuel lines connect to the tank. not sure that can be done without removing the floorboard (or even how to remove it).

And did you get your issue with your FIP resolved?

Thanks much!

Mike