MF 150 Stalling - Did I say Help? Help!!!!

[Rebol]

Hello Y'all.

Well, if I ever get my 1967 diesel MF running for any length of time I will be soooo happy. Just did a head gasket job on it but now I can't get it moving without it stalling. It will idle forever but when I press on the fuel pedal, outside of ginerly doing it, she stalls.

Here's what I have done since discovering this issue:
1. Drained all the old fuel
2. Blew air into the fuel line to the tank to clean it as it was not flowing as much as it should.
3. Changed the sediment bowl as it had a small crack in the lip.
4. Replaced the fuel filter.
5. Cleaned out the lines from the fuel filter into the injector.
6. Just replaced one of the hoses leading into the fuel pump since it looked a bit worn.
7. Have disconnected the air filter to make sure it wasn't that.
8. Inspected all the connections for any signs of moisture.
9. Air bled her more times than I can count.
10. Prayed a lot.

I can rev up the engine if I do it very slowly. I'm thinking there must be an air leak or something but for the life of me I can't find it. Or maybe it's something completely different.

Any ideas?

Thanks so much for any input.

 

[MasseyWV]

Nevermind, I see that you said it was a diesel. I really need to stop skim reading. :confused2:

 

[flusher]

I'd take a good look at the injection pump. Unfortunately, the MF service and parts manuals are no good for that pump (at least that's the way it is with the manuals for my 1964 MF135 diesel). Understandable, since MF didn't manufacture the injection pump so there's nothing in the MF manuals about the guts of that pump.

Good luck.

 

[the6shooter]

have you checked for a kink in the fuel lines ? have you losed up the injectors and bled them from each injector ? and last but not least, is the fuel line too small ? Can't think of anythin else, beczuse the pump has already been covered.
david

 

[Rebol]

Thanks for your replies.
The6shooter - I have checked before but I will check tomorrow again for kinks. You know, I have not loosened the injectors. I thought that since I've had it running for up to 40 minutes at a time that the injectors were not an issue. But if you think that could be it, I can do that. The fuel lines are the standard 1/4". I replaced a small section of it with fuel line of the same diameter a while back so I could have a better way to manage the the connections to the fuel pump. That was some time ago and it ran just fine with those modifications.

Flusher - I do have an fuel injector manual more or less. It's a CAV. The AGCO parts site also has some good views of the parts. I have in the past worked on the injector, replacing the O rings.

After looking at several threads from the past I'm wondering if it really isn't something in the fuel tank. I'll clear it again and check.

Again thanks for your concern and advice. I appreciate your help and wisdom.

 

[the6shooter]

Rebol, all it takes is an air bubble in the fuel lines at the collector rail or the injectors, to disrupt the fuel flow to the injector. almost like a dirty fuel filter does. It will idle, but once you demand power it runs short.
I hope this makes sense.
david

 

[Rebol]

Is that right? Hmm. I did re-clean the line from the tank to the pump once again. The next item will be to bleed the injectors then.

I should ask have you've seen this same behavior before?

Thanks,
James

 

[Rebol]

Oh, yes, I did check also for any kinked cables. None found.

 

[the6shooter]

yes I have seen it before, the cure was to loosen the injectors one by one, and purge them. you don't have to compleatly remove them just break them loose enough for the air to get out. other than that maybe the pump is weak.
And you know what that means $$$
david

 

[Rebol]

Thanks David. I did crack them yesterday but still have the issue. I did, for the first time notice what I think is some moisture on one of the lines. I'll get at that today.

Thanks again. I really appreciate it.

 

[Rebol]

Well, that wasn't it (the line I suspected). I was thinking though that perhaps I am not bleeding it to the point where all the air is really out of the system. Since I was regularly trying so many different things and having to bleed it after those attempts, perhaps I was not being patient enough. I say this because every once in while after I think I've got it, I get some bubbles from the upper drain of the fuel injector.

Anyway, she's still sitting there waiting for just the right thing.

 

[Rebol]

Yesterday I let her idle for more than an hour but she stalled as soon as I stepped on the gas as usual. At this point a friend and I will check out the CAV fuel pump.
The great news is that she really runs pretty well and the original head gasket problem is fixed.

Let you know more when we get there.

Note: I just went out to take down some numbers and saw some moisture on the fuel inlet of the injection pump. My thought is that didn't show up until I ran it so long. This could be it! At least it's something different.

 

[Rebol]

Alright. I unloosened and re-tightened the line leading from the fuel filter into the injector pump. No moisture there. I got it running but it again stalled but I thought, well, why not try to move it from its resting place of a couple of months? As long as I didn't "gun" it she should move. And yes, she did. Once closer to the garage, I thought what the heck, let's see if she stalls and she did that too. Well, I dismounted and checked everything again and I thought I saw a drip! I wasn't sure if it was residue from my bleed attempts but I saw a droplet forming from the filter where it mounts up against the filter holder. Aha! I've always been afraid of over tightening that since I have a glass bowl but I have a spare so I decided to be a bit more cavalier about it. My guess is that was the main culprit after I changed the cracked bowl a few weeks earlier. It just didn't appear until I moved the tractor.
It behaves much better now though it's still a little touchy with the accelerator. I'm pretty sure that my injector pump needs some love. That's the next project.
It's going to rain for a couple of days so I'll get my chance to actually test it out when I go to smooth my driveway.

Thanks for all your help guys. Trust me. I needed the moral support.

 

[Dieseltech]

MF Perkins final filter has a small bleed fitting on top of filter base with a small line returning back to tank, may be straight or banjo type fitting. Has small .020 hole that sometimes plugs and will not bleed any trapped air out of filter as it should, if plugged air can get to injection pump and engine will die. Have worked on MF equip and diesel injection pumps for years, is worth a look.

 

[Rebol]

Thanks DieselTech, that sounds good. I appreciate the help.

 

[Rebol]

DieselTech,

Thanks for the advice again. I cleaned out that part(s) today. There was the banjo bolt and the valve. It wasn't particularly clogged at least not visably. It still stalled when I pressed on the pedal quickly. Of course, I didn't let it warm up and I wonder if I am even supposed to be doing that. After it stalls though, it is not easy to get it started again. I usually end up going back to the hand pump and make sure the top bleed nut on the injector pump has a good flow going.
Now that I think about it, I didn't stick anything physical into the banjo bolt to make sure it was clean. I focused mainly on the valve and making sure the little ball was mobile. Maybe tomorrow I should go back to that.
Of course, I should ask if this behavior of my tractor sounds like an air problem to you.
Thanks

 

[Dieseltech]

Make sure bleed hole is open, also may want to recheck filter sealing rings, top groove seal is a little bigger than lower seal, make sure it is not twisted in groove. Have seen air leaks past faulty seals but no fuel leaks. Keep us posted on your progress, will try to help where we can.

 

[Rebol]

Thanks and so does that sound like air in system behavior? I will check the rings again. I matched them up before I put them because that top one is slightly tricky.

 

[Dieseltech]

There are 2 pump bleed screws, do you get good flow out of screw next to tag? That one is most critical, cover screw is to get trapped air out of top so governor parts don't rust. Family has had MF equip for years, I worked for MF dealer years ago before starting in diesel shop in 1976. If you like, call 574 893 4172 after 7 PM IN time, be glad to help.

 

[Rebol]

Wow, thank you so much for your offer and the information. I'm going to speak about the most recent air-bleeds since I feel like I've done it dozens of times. I get much more flow out of the top screw if I compare them. The top one, after manually pumping and opening it will flow with a stream while the one below generally drips down the side. The one below, is by the tag. I will work at the bottom one to make sure I get a good flow like the top and give it a try.


Thanks.