MF 231 won't start, engine turns over strong

[Ohio Doug]

Hi All,

First off, this is my 1st post, so please excuse my rookie errors. Not even sure if I'm posting in proper "place"?
I have a 1997 MF 231 (not MF 231S) that always started strong on first attempt w/o ever giving it gas, but now won't start.
Has a strong battery.
I inherited this tractor from recently passed father-in-law.


Over the past month, noticed it began to take 2-3 attempts to start it, but thought nothing of it.
So yesterday it started on the 3rd attempt, let it idle for a minute or 2, then I revved it for about 4 seconds (in neutral/park) and it died while revving and now won't restsart.
It's 80 plus degrees in Ohio so cold temps are not the issue.
I have never owned anything w/ diesel engine, so I'm a rookie at that also.
Engine turns over fine/strong, just won't fire.


what could be the issue?

added/edited: Fuel tank is plenty full; has old fuel, but started 50x this summer. Have new fuel filter in garage, but have not installed yet. I do not know past maint records.


Thanks.


Ohio Doug

 

[DLTTrekkers]

Hi All,

First off, this is my 1st post, so please excuse my rookie errors. Not even sure if I'm posting in proper "place"?
I have a 1997 MF 231 (not MF 231S) that always started strong on first attempt w/o ever giving it gas, but now won't start.
Has a strong battery.
I inherited this tractor from recently passed father-in-law.


Over the past month, noticed it began to take 2-3 attempts to start it, but thought nothing of it.
So yesterday it started on the 3rd attempt, let it idle for a minute or 2, then I revved it for about 4 seconds (in neutral/park) and it died while revving and now won't restsart.
It's 80 plus degrees in Ohio so cold temps are not the issue.
I have never owned anything w/ diesel engine, so I'm a rookie at that also.
Engine turns over fine/strong, just won't fire.


what could be the issue?

added/edited: Fuel tank is plenty full; has old fuel, but started 50x this summer. Have new fuel filter in garage, but have not installed yet. I do not know past maint records.


Thanks.


Ohio Doug

Did you fiddle with the chokeknob ? Turning it in to tightern it ?
Is that knob pushed in for starting ?
Is there water in your diesel ?
Loosen 1 injectorpipe and try to start and see if diesel comes out of the inj pump ?
Did you forget to open the tanktap ?

 

[thepumpguysc]

You already know the fuel is old.. I think you've been pushing your luck.. NOTHING GOOD has ever come from using dirty old diesel fuel.. other than a nice big fire or killing weeds..
Is your engine "gravity fed" or does it have a lift pump?? START THERE.. AFTER you change the fuel filters & drain the tank & put 10 gallons of fresh fuel in it..
Disconnect the fuel feed line going TO the injection pump.. if it has an electric feed pump, turn the key on & a steady stream w/ about 6-10 psi should come flowing out..
IF its a mechanical feed/lift pump, nothing will come out until you crank/spin the engine over.. your looking for the same thing.. lots of fuel.
DONT just "bump" the key.. SPIN IT.. & check the flow..
IF its gravity fed.. the fuel should be at the inj. pump inlet & still come flowing out GOOD..
Let us know how you make out.

 

[Ohio Doug]

Thanks Gents for responding! I basically used your methodology but didn't loosen injection pump lines nor injectors.
Here's the update...
Removed fuel filter, things looked clean, with it still off, I cranked the engine and no fuel came into the manifold area where the filter WAS.
By the way, the injector pump is NOT electrical, it's mechanical.

So I started to remove/loosen fuel lines back towards the fuel tank (the part of the system that's gravity fed), still no fuel flow. Didn't even have fuel draining out the petcock at the discharge of the fuel tank. Removed petcock and about 8 gallons of diesel drained onto the barn's dirt floor. Petcock was plugged solid and hard w/ gunk. So problem found!

Now what to do? Do I remove fuel tank to clean.? There's gunk/wax about 1/32" thick on bottom of tank. Should I flush it w/ more diesel with tank still in place? Then leave it at that. Regardless, I will replace petcock ***'y. The microfish shows "gauze" at the inlet of petcock (sticking into the tank), but there was no sign of the gauze. Was it ever there or did it disintegrate? Is this gauze like a pre-filter of sorts? I almost rather clean the new petcock ***'y a few times over the next year than remove tank. Thought?

 

[gimmodog]

I would try to clean it out in place. pressure from water hose or air hose should loosen up the gunk and let it flow out the petcock opening. If you do use water make sure you let it dry completely before you add new fuel. Maybe some type of solvent will break up the gunk also, don't know what type to use tho, maybe parts cleaner solvent might break it up. AGAIN make sure you have the tank completely dry before adding fuel

 

[thepumpguysc]

Yup.. flush it, dry it & fill it..
If you can, get a shop vac down the neck.. be sure & take off the shop vac filter..
Glad you found the problem.. old waxy fuel.. You must not run it much for it to separate like THAT.??
DO NOT reuse the fuel.. its garbage now.. use as a weed killer or fire starter.. {if it'll even lite. lol}
IF you have the 3-4 piece filter set-up.. long bolt that goes down the center of the filter.??
The big oring goes "UP IN" THE FILTER HEAD.. NOT "ON" THE FILTER.. Good luck..

 

[Ohio Doug]

Thanks for the continued help guys.
Great ideas and I feel good moving forward w/ cleaning in place.
I'm gonna use combo of all your suggestions.
I cleaned the old petcock until spotless. Reinstalled it tonight (and closed the valve). Added a few ounces of some stuff from Autozone that's more of a high powered diesel fuel tank cleaner than injector cleaner (although does both). Then added 2 gal of FRESH diesel and will let it soak tonight. Drain, rinse, repeat. The sides of the tank are much deeper (has pockets) than the middle so I'm afraid to use water but will do compressed air and shop vac idea. The wax is soft so hopefully this solvent helps it release from the metal, if not the comp air will help.


Pump Guy, as far as the filter, yes it might be the 3-4 piece. I did remove the old o ring UP IN the head and replaced w/ new. So that takes care of the TOP, at the bottom of the filter, a clear bowl fits on, and yes, the whole assembly is held together w/ a long bolt down the center. The OLD filter had the exact same size o ring as the top, at the bottom. (between the bottom of the filter and the clear bowl). The new filter had 3 of those o rings, so I guess there's an extra? However the o ring at the bottom didn't have groove for it to seat in, so was difficult to assemble and keep sandwiched while putting the bolt thru and tightening. There's not 2 extra o rings are there?
Lastly, we think alike, 4 gal of the old diesel is already in my 4 gal back pack weed sprayer, with 2 more gal in milk jugs waiting for sprayer usage.

 

[thepumpguysc]

If you bought a "WIX or NAPA" filter, the oring chokes off the fuel if you put it ON the filter..
If you got a CAV or Delphi or Baldwin filter it doesn't.
The oring goes IN the bowl on the bottom & depending on which filter you bought, it'll have a slight groove on the bottom of the filter canister itself to help seal..
Granted, its a PITA.. but that's the price you pay for "saving" a few cents on the filter purchase.

 

[Ohio Doug]

Thanks pumpguysc,

It's a NAPA. Didn't do a price search, just went to closest place to house. Old fuel filter was Agco.

Update: Flushed tank a 2nd time, will do one more, then move on.

 

[Ohio Doug]

Update: flushed tank 3 more times, put it back together and got it started tonight.
Thanks all for the help!