# John Deere 950 loses power and can't get rpm's up! Please help!!



## Jb800 (May 17, 2015)

I have an early 80's John Deere 950. I starts good and ran fine. I was rototill ing for about 1/2 hour and then it started to lose power. It progressively got worse. It got to the point that the tractor would barely go and I couldn't get the rpm's up. It felt like a restriction. I managed to get it back to the house. It sat for about an hour then started good and ran good for about 10 minutes then it was back to no power, can't get rpm's up and felt like a misfire. It's not overheating. Gas filter was changed not to long ago. Air filter is brand new. Just filled it up with fresh diesel. I loosened the gas cap to make sure it is vented ok. Not sure what to check from here! Does it have glow plugs? Injection pump going bad? I'm hoping its an easy fix. It ran perfect last week when I used it. I would hate to bring it to the dealer and get hit with a big bill if its something I can fix.


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## BigT (Sep 15, 2014)

Howdy Jb800,

Welcome aboard the Tractor Forum. 

You have an obstruction in your fuel system somewhere. I would start at the outlet of the fuel tank. Look for debris on bottom of tank and in the opening to the fuel line. 

Does it have a mechanical or electric supply pump? If so, check that it is working.

Do you have any fuel screens in the system? If so, check them. Possible places for screens...in bottom of tank, in sediment bowl, at inlet of supply pump, etc.

Flow check the fuel line at connections to see that flow is not restricted. I once found an obstruction in my fuel line giving the same symptoms as yours. Looked like wadded up cobweb in the fuel line to the fuel filter. Removed it and my tractor has been running fine for many years.


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## Jb800 (May 17, 2015)

Yea thats what I was leaning towards. Some type of a restriction somwhere. I ordered a new gas filter to start. Im not 100% sure on how and what exactly to check.


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## Fredneck (May 25, 2012)

welcome to TF, jb 

easy way to test the filter - remove it, drain it, clean it off and then try to blow thru it. if u can't, or can only barely, that's your likely culprit.

if your system has a source of dirt/whatever, you'd be amazed at how quickly a new filter can plug up. in a perfect world, a clear plastic filter is ideal, since u can visually inspect it.

the symptoms definitely sound like a plugged filter/screen. what happens is this: as u use it, more and more sediment gets sucked up against the filter element, to the point where fuel no longer flows freely. when u shut it off and let it sit, the sediment will often settle back off the filter element. that's why it will work again, but only for a few minutes, as it will pull that sediment back into the filter element while running. lather, rinse, repeat.


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## Fredneck (May 25, 2012)

ps: amen to what BigT said about looking for crap in the fuel tank. i've got a quad with a rusting gas tank. that thing will plug fuel filters over and over again.


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## Petespix (Sep 20, 2014)

Hope you can remedy this problem yourself and not have to bring it in for service. I found your post here this morning in searching for help as my New Holland TZ is currently experiencing the same exact problem. It did the same thing last year and the dealer charged me somewhere around $800 to fix!!! Not again, so I appreciate the advice given here to your question by Fredneck and BigT. Thanks!


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## n194060 (Sep 5, 2015)

I'm new to the site today and just want to say thanks to all that help and especially big t. I have changed air and fuel filters but still runs about an hour sputters and quits. Leave it overnight and it will run another hour or so. Its a diesel so next I will drain the tank b4 I get into deeper woods. I'll be reading often for you fellows experience and advice. Thanks again


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