MF40 Industrial won’t start after 12 years

[Sibaird_mf40]

I have a MF40 backhoe with the Perkins motor. I started it up after about 12 years and it ran for about 20 seconds. I believe I had the fuel shut off and so now it’s full of air. I’ve replaced and bled the fuel filter ,and the 2 bleeders on the injection pump. The manual hand pump works fine, I’m able to pump fuel to these areas and push the air out. I cracked the top bolt on the injectors and only some fuel came out, there has been some air bubbles also. Still the tractor won’t start.

Should I be bleeding the injectors at the fuel line that connects to the injector? I’m assuming the top line that connects all 3 injector is a return line or something? I read that I should crack them open then crank it to force the air out?

It ran perfect for 20 seconds like I said and it acts like it wants to start on ether, so I assume it has spark. Oil PSI goes up to 40-60 range while cranking. There is also a small amount of white smoke coming out of the pipe.

I know very little about diesels so please fill me in.

 

[Dieseltech]

Leave the line across the injector TOP alone, you need to loosen each injector INLET nut to bleed the air out while cranking the engine. What brand filter did you use? If NAPA/WIX make SURE there's NO O ring in the filter top OUTER groove, that's the fuel inlet passage on that type filter and must NOT be blocked with an O ring.

 

[Sibaird_mf40]

I replaced the filter with the same one it had on, it was a WIX 33166 I think. It came with 3 big O rings and 2 small ones, I put them where I removed the old ones. The sediment bulb on the bottom filled up quickly from using the manual pump.

 

[Dieseltech]

I replaced the filter with the same one it had on, it was a WIX 33166 I think. It came with 3 big O rings and 2 small ones, I put them where I removed the old ones. The sediment bulb on the bottom filled up quickly from using the manual pump.

There are two bleed screws on the injection pump, the LOWER screw MUST be air free for the pump to bleed air out to injectors. The top bleed screw can be checked for air after engine is running.

 

[Sibaird_mf40]

There are two bleed screws on the injection pump, the LOWER screw MUST be air free for the pump to bleed air out to injectors. The top bleed screw can be checked for air after engine is running.

Yes both are air free, I have checked them multiple times and no air bubbles are coming out.

 

[Axtell]

This is a little drastic, but you can try to give it a shot or two of ether while cranking. Hopefully it will eventually crank and work out whatever ails it. If it cuts off or fails to crank back up, then there is still a problem somewhere. A clogged in-tank filter on the shutoff valve can cause headaches. Its possibly there is some trash that got stuck to it that's preventing the right amount of fuel to be delivered. Here is one I replaced during a rebuild on a 35, granted it did not prevent the tractor from cranking, but it just shows you how nasty they can get over time.

 

[Sibaird_mf40]

It will try to start on ether, and even run for a second, but then die. I think it is getting enough fuel, though I have had concerns about the tank filter/fuel switch. Thanks for the input.

 

[used red MN]

Since you likely do not work on diesel systems daily and you used Wix filters I am or at least the linked post will show you better than DTs pictures of what the concern is. Just remember the filter’s narrow outer raised rib seals against an oring in a groove up in the housing. No other oring is needed at the upper outer diameter.
Filter and oring issue

 

[Sibaird_mf40]

So I didn’t put one in the groove of the filter, just around the housing where the old one was. There was also a small Oring in the middle that I replaced as well.

 

[used red MN]

Sounds like you have it all correct. The picture in the post I linked just makes the issue much clearer to understand. I also hope you know that it is running on the either as fuel. I would not discount the idea that something in the pump stopped working. Some debris broke loose floated into the wrong spot and stopped the flow or movement of a pumping element.

 

[Sibaird_mf40]

Ok, thank you for the input. I plan on working on it this weekend. Gonna crack the injectors and try that first. Hopefully it isn’t the injection pump.

 

[Dieseltech]

Injection pump MIGHT have stuck internal parts setting that long with stale fuel. I repair/calibrate a lot of pumps that have stuck parts that have set unused two years or less. ANY traces of water in fuel, or Bio diesel will cause stuck parts quickly.

 

[Sibaird_mf40]

Ok thank you.

 

[used red MN]

Injection pump MIGHT have stuck internal parts setting that long with stale fuel. I repair/calibrate a lot of pumps that have stuck parts that have set unused two years or less. ANY traces of water in fuel, or Bio diesel will cause stuck parts quickly.

DT, he did say it ran for 20 seconds. But you and I both know just about anything can happen inside of one of those pumps.

 

[Sibaird_mf40]

Injection pump MIGHT have stuck internal parts setting that long with stale fuel. I repair/calibrate a lot of pumps that have stuck parts that have set unused two years or less. ANY traces of water in fuel, or Bio diesel will cause stuck parts quickly.

So I’m back on the farm right now, I cracked open the injectors inlet lines, nothing came out. I cranked the engine for awhile, a tiny bit has come out of the first injector. After a few minutes of cranking all 3 of them now have a small amount coming out. Really it’s just enough to dampen the area, not a steady stream like I’m sure it needs to be.
The injection pump has plenty of fuel in it, so it seems like either I have clogged fuel lines (unlikely I’m sure) or the injection pump needs to be replaced/rebuilt???

 

[Jim.ME]

So I’m back on the farm right now, I cracked open the injectors inlet lines, nothing came out. I cranked the engine for awhile, a tiny bit has come out of the first injector. After a few minutes of cranking all 3 of them now have a small amount coming out. Really it’s just enough to dampen the area, not a steady stream like I’m sure it needs to be.
The injection pump has plenty of fuel in it, so it seems like either I have clogged fuel lines (unlikely I’m sure) or the injection pump needs to be replaced/rebuilt???

It is not a steady stream, more of a small spurt is sent to each injector in time for that cylinder to fire.. And with the nuts just cracked loose the fuel may only appear to dribble out around the nuts. Have you tightened the lines and tried it again?

Where are you located and what is the air temperature around the tractor?

In your first post you mentioned thinking it has spark. Your diesel does not have an ignition system like a gas engine so no spark. Your diesel needs atomized fuel, air, and heat to make the fuel burn. The high compression makes the heat. The engine turning over fast helps make the heat in the cylinders.

 

[Sibaird_mf40]

I haven’t tighten the nuts yet, they are a pain to get to under the tank, I will do that after lunch.
I’m in western Kentucky, temperature around 50 degrees. Just seems like there isn’t much fuel coming out of the line. I’ve cranked it for probably 3 minutes total with not even enough coming out to create a puddle underneath.

 

[Sibaird_mf40]

To update, I tighten the nuts, cranked for awhile, nothing. I loosened the nuts and watched it while cranking, could see small air bubbles coming out around the collar of the nut, they seem to be dripping now every so often. Definitely more fuel than before, I tightened them down and tried it but still not wanting to start. Gonna keep trying this.

 

[Axtell]

To update, I tighten the nuts, cranked for awhile, nothing. I loosened the nuts and watched it while cranking, could see small air bubbles coming out around the collar of the nut, they seem to be dripping now every so often. Definitely more fuel than before, I tightened them down and tried it but still not wanting to start. Gonna keep trying this.

Did you ever check the fuel shutoff valve filter at the tank? After sitting 12 years there may be trash/sludge buildup.

 

[Sibaird_mf40]

No, that may have to be next on the list, I’m not sure the best way to check it, Im thinking that just taking the tank off and cleaning it would be best, as the whole tank is caked with debris. I’ll replace it when I do that.

I might just get a temporary fuel tank so that I can take this one off and still be able to work on it and try to get it started.

Would the manual fuel pump have anything to do with the problem?

So far I have cracked open the inlet nut at the injectors, it seems to be free of air, there is now a slow stream of fuel coming out of them.