MF 135 Cutting out randomly

Howdy everyone,

I have an old massey 135 1969 UK model. I have had it for over a year now and I've drained and replaced the transmission fluid, changed all filters, and replaced all fluids, as well as installed a glow plug for our cold Canadian winters.

The thing is running like a top, except everyone once and a while (3 times in since I've had it) it cuts out. There is no warning to this it just cuts out while I'm in the middle of a task etc. In the summer I assumed it was overheating a bit on the really warm 90F (30C) days at the peak of summer, but today it cut out while plowing snow in the middle of winter. Generally I let it sit for 12 -24 hours and then it starts up again no prob.

Only things that are mildly odd about the tractor is that every one in a while it will surge (I'm relatively new at mechanics so I think it is surging anyways) which is to say it all of a sudden increases RPMs of the engine without me touching the throttle, very minor increase in RPM and then it'll drop back down. You can also hear a very very light moan in the engine like something is very gently rubbing up against something else, but you really have to pay attention to hear it.

Lastly I accidentally ran it with a pretty low tank of fuel (Diesel) recently and sometimes when I do that it seems like I let air into the fuel line and I have to bleed it to restart the thing. I'm going to try to bleed the fuel line again on Thursday and try to start it up again. (Its in the middle of my 300 foot driveway causing me to have to walk up through the snow now) I can't reach the thing with my extension cord to plug in the tractor but luckily they're calling for a February thaw on Thursday.

Anyways any suggestions as to what might be causing this thing to cut out every once in a while? It just loses power, I can tell its going to cut out, I even try taking it out of gear to see if the engine will just idle but she quickly cuts out and doesn't restart (I tried waiting 10-15 minutes but it just turns over and over without starting)

Cheers, and thanks,

I have seen this before. The first thing to check is to insure that you have good flow to the pump. next you may consider removing the tank and cleaning it. you may do this first. a piece of contanination may be floating in the tank and intermitently plugging the inlet. there is a screen in the injector pump @ the intake line. remove the line and the nut below it, there is a screen, It may be restricted. If none of this reveals a problem, It is possible that you have a intermittent failure in the pump itself.

Hello,
I would agree with Glen. I have also seen this before with my own 1965 MF 135. As Glen has said the filter on top of the fuel tap is the first place to start. It is essential that there is a filter here moreso than with the 165 upwards. The well at the rear of the tank tends to collect any rubbish in there and it soon finds its way to the tap. Add to this the fact that you have run the tank low. Always advisable to fill the tank at the end of the day not the beginning of the next. This way reduces condensation. If the tap filter is in place and clean then the next stop is the lift pump. Do you have the glass bowl type? If its the glass bowl you may see air bubbles circulating inside. If the valves in the LP are worn or stuck open with debris you can loose low supply pressure to the main pump. Given a combination of working angle, low fuel and debris this might well cause the engine to cut out. Check the plastic pipe between the tap and LP for cracks etc.
My belief when this happened with my 135 is that there is an intermittent fault in the main pump. I never failed to restart it immediately so it was never investigated further.
One other thing to check. I have only seen this with MF 500's but it might just be possible that the fuel cap is not breathing and allowing a vacuum to be created inside the tank which the LP cannot overcome and consequently no fuel flows.
Let us know if you find anything.
DavidP

Thanks for the replies! I will very much consider cleaning out
the tank as a permanent fix to this problem, or perhaps its the
pump. At the moment I"m just trying to get it to start so I can
get the thing out of my driveway. My main problem at the
moment is that its over 300 ft from my house now and I don"t
have an extension cord long enough to plug it in. I tried starting
it tonight in the dark at a temperature of 0 C (32F) but she
wouldn"t turn over. I bled the lines and took out all the bubbles
so now I"m at a loss as to what could be going on with the old
lady. I"ve got to get it out of driveway. Will starting fluid be
advisable in this emergency situation? I"m committed to fixing
the underlying problem but only inside away from the -10 C
weather that is forecast for next week.

Thanks for your help again!