Mf135 engine died

[James paul]

My Mf 135 engine died today. It wouldn’t restart but then I bleed it at one of the injectors and it started up pretty quickly. I was trying to figure out what had caused the airlock and then I noticed that the lower bleed nut on the injector pump was loose, loose enough that I could turn it with my fingers, so I was wondering if enough air could have been sucked in through that nut to stop the engine. Thanks.

 

[Lincs Lass]

Slightest amount of air will cause problems ,,they cant bleed it out through an injector unless you slacken one for it to escape

 

[James paul]

Yes I slackened one of the injectors. The small bleed nut I mentioned was rounded off, which might explain why it was loose, I’ll try to get a replacement. Thanks for your reply.

 

[Flatlander]

Take the screw out and grind some shoulder on it. They don’t need to be super tight to hold unless damaged. You’ll be lucky if you can find a replacement easily.

 

[bravheart]

Interesting would the pump bleedscrew actually allow air in from being slack? It's job is to let air out.
Would have thought that the original problem would be caused by a restriction in the fuel flow somewhere first then perhaps air getting in.

 

[agrimax]

Replacements are easy to get...

cav dpa bleed screw - Google Search

 

[James paul]

The tractor engine died again today and it started up again after I slackened two of the injectors. The bleed screw was tight this time so we can rule that out. If there is a restriction where should I check first? The small filter that goes up into the fuel tank maybe, since it is the first one the diesel goes through. I will have to unscrew the small tap under the tank which means draining the tank of fuel first. Does anyone know an easy way to do this?

 

[MF-ANDY]

The tractor engine died again today and it started up again after I slackened two of the injectors. The bleed screw was tight this time so we can rule that out. If there is a restriction where should I check first? The small filter that goes up into the fuel tank maybe, since it is the first one the diesel goes through. I will have to unscrew the small tap under the tank which means draining the tank of fuel first. Does anyone know an easy way to do this?

No easy way. Get yourself tapered dowel or a plastic bung to put in the hole after you remove the tap. Either way it will be messy.

 

[bravheart]

Would say check filter in tank first then gauze in the lift pump, think from memory there might be a water separator to check as well then fuel filters. Don't know of an easy way for tank filter except roll your sleeves up and if its drawing air I would be inclined to change all the rubber seals on the filters, glass bowls etc.

 

[agrimax]

Why not just syphon the fuel out of the filler hole?
If yours has the glass bowl on the lift pump,there should be a gauze above the bowl. Then there's the filter inside the inlet end of the inj pump... Need to be extra careful in removing it,if it's still there.

 

[Hair Bear]

Before you take the tap out I'd be tempted to take the pipe off the tank first to see if there is a good flow. If there is, then move to the next component down the line. If not, you've likely found your problem right there but you'll still wear a load sorting it.
If you go straight for the tap removal you will never know if there was a problem there or not.

 

[MF-ANDY]

It will be the tap. Start there. Clean or replace the gauze filter. Replace both filters. Tank will be full of sludge/rust and you probably end up removing it to clean it out.

 

[TripleSix]

The taps themselves like to block on a 35

 

[Hair Bear]

If you take the pipe off and nothing comes out, before you do anything else take the tank lid off in just case the breather is blocked.
Our old Major ground to a halt one day, took the pipe off the tap - nothing. Unscrewed the tap and gauze - nothing. Hmm... not long put fuel in it so, poked a bit of wire up the tap hole to find the crud had formed a near complete crust seal around the gauze. And yes, after a blast with the air line, wore most of it.

 

[James paul]

In reply to hair bear above, no diesel came out when I unscrewed the pipe. This was before I read your comment so I didn’t try taking the lid off.
There is no filter fitted to the tap just a little pipe. There was some muck inside which I blew out with carb cleaner and compressed air. The tank has some dirt inside but really isn’t too bad. a couple of questions:
Is it enough to flush out the tank without removing it?
should I replace the small pipe with a proper filter?
can I test the breather in the lid?

 

[MrNoo]

They normally block at the 90 degree bend, tank doesn't look too bad at all. Does the black tube on the tap have a angle cut in the side of it to allow fuel in or is it drawing from the top? We used to clean the filter on our old 165 but in the end did away with it and put a tube in it like you have. At least next time it blocks you can get a rag on the filler and an airline at low pressure, that will normally blow and crap caught in the 90 degree bend out, turn the tap off and refit fuel pipe and should be good to go.
I would add that the tap you have does look a little corroded where the filter would normally fit so suggest maybe that this is the reason why you have a pipe in the ID of the tap. I am pretty sure you can get new taps/filter etc

 

[James paul]

I didn’t notice any cuts on the pipe, I think it’s drawing the diesel in from the top. I assumed it was used so that sediment would be left on the bottom of the tank and clean diesel taken from higher up.
Could you explain again the clearing of the 90 degree bend. I don’t follow what you said about ”a rag on the filler”. Are you blowing dirt in the ninety degree bend away from the tank rather than back into the tank?

 

[Hair Bear]

The 90 degree is in the tap. Fuel goes in the tap vertical and out sideways = 90 degrees.
So if it happens again, take the pipe off the tap, turn the tap on. Take the lid off the tank and get a large piece of rag that will screw up enough to form a bung in the top of the tank. Then push the end of your airline into the top of the tank and blow. The desired effect is to introduce a bit of pressure in the tank to blow the crud out of the system and not back into the tank.

 

[JVM]

Agrimax speaks truth when warning about checking the filter at the inlet to the injector pump. With the big 'nut' off, you will see the end of a spring which is inside a tube filter. The filter is on a valve in which there is a floating piston. Below that is another spring. When the filter is removed, there is a risk that the floating piston and spring will drop into the bottom of the chamber preventing the other parts fitting back into place. I've put a diagram of the assembly on one of my posts re MF4225 fuel starvation. All of this from personal experience!

JV

 

[James paul]

”Cow Farmer Dan” did a YouTube video on changing that injection pump filter. The video was called “Bleeding a Massey Ferguson fuel system”.
I’ll try the bung and airline trick the next time the engine dies. Anyway I cleared the the fuel tap of crud and changed the filters. I cleaned the lift pump glass bowl and the gauze that sits above it. I flushed out the tank a couple of times as well. The engine is running fine.
This tractor is only used a few times a year and i am thinking that maybe this is what caused the problem.
Thanks to everyone who replied to my questions. Your help is appreciated.