Mitsubishi MT250D, rebuild log / questions

[bnjleouf]

Good morning everybody, Ben from Texas here.

I figured I'll join your comunity and share experience with you guys,

I just bought a little Mitsubishi MT250D, with a FEL on craigslist. This thing is in poor conditions, didn't start and was left out in the weather for a while, I can tell.

Previous owner wanted to rebuild it, but he felt overwhelmed on the labor it'll take to put it back on the field.

I bought it, because I already own a little international 254, and wanted a loader for it. Since the MT250D and the international 254 are very similar (both built by mitsubishi, and sharing a lot of parts) the loader was a direct fit to my international, and considering the very low price, I couldn't let that go.

Oh well, now I have the little mitsubishi in my shop, and you know, I kinda fell in love with it... So instead of robbing parts from it, I started investigating on the engine issue. It is a Mitsu K3H block, (the international has a mitsu K3E)

My daughters even gave it a name : R2D2 (it's white and blue see pictures !), the international goes by the name of Wall-E

The tractor is almost complete. I'm missing the transmission shaft for the front axle (they probably took it off when they installed the loader), and the bars and links for the rear attachements (no big deal). Brand new tires, which is a good sign : Who would put new tires on a non working tractor ? So I figured it has not been down for too long, or it failed all of a sudden, not gradually.

First : Compressions. Cylinder #1 : 20 PSI ... Ahem... Cylinder #2 : 200 PSI ... Better, but less than ideal... Cylinder #3 : 200 PSI. ( according to the I&t book, it should be 425 PSI new)

According to the hours meter, the motor had 1650 hrs running, but it might have had bad maintenance to it, this thing is worn out !

Disabling the cylinder number 1, oil level, and priming everything with fresh diesel, I could get the baby to fire up. Which was really not the best to do on a shot engine, but I wanted to test all functions before I decided to rebuild it or not.

Hydruaulic works great, loader functions very nice, attachment lifter works good too, PTO seems to work good too.

Lot of Blow by, pressure in the radiator, and water in engine oil. My hope was that it was the headgasket.

This is also when I realized that the clutch is stuck, and the pedal has no effect on anything (very soft travel, you can push it with your pinkie !) So i think the release bearing must be gone.

Next week end, I then opened the head, to realize the gasket was in great shape, no cracks. All bolts were tight as well. On to the pistons (with the precious assistance of my 7 years old daughter for the support and wrench handling!), and yes, cylinder number one lost its rings, and the piston looks quite bad, but the cylinder had very little damage.

I'm gonna go to a piston rebuild (can't find pistons for K3H anywhere), the piston is mainly damaged around the tracks for the rings, but other than that is not in bad shape. So I can rebuild it.

Honing the cylinders, put a new set of rings on all 3 pistons, and a new headgsket should give this engine a new life. That will be for the next week end, and the thanksgiving week.

For the clutch, I'm going to split the tractor, and check what's going on. A clutch kit is only 200 usd, so I ordered it, and will see when I split it.

I will get a little wire camera from on of the drain port on the clutch housing just to make sure I have no bad surprises.

I'm kind of scared to do it, since it'll be my first tractor split, but I'm also excited at the idea of doing it, and I have nothing to loose on this tractor, since I paid less than the price of the loader and tires for it !

So this is the begining of the story for me and this little Mitsubishi.

I'm looking for this transmission shaft, if anybody has a lead for this, I'll be glad to have their input for it. I can modify the loader frame so it'll allow the shaft to be reinstalled.

If I can't find it, I might just do a custom one with a pipe and two U joint couplings.

Let me know your thoughts, any kind of support is greatly appreciated !

Yall have a good day !

 

[bnjleouf]

Just got the piston rebuilt by a welding shop, they did a great job salvaging those pistons.

they saw better days, but at least, they'll hold their rings now, and I'm sure my compressions are going to be better than what I found originally !!

Waiting on the new rings and main bearings from weaver tractor, those guys are great to work with, they called me because they caught that I didn't order the right main bearings for the model rings I did order !! So they called to confirm everything was for the same tractor, which i think is awesome ! got my order corrected right away, and I'm getting my parts hopefully before the week end, so I can put it back together.

I'll keep on following up on here.

 

[bnjleouf]

I received a lot of goodies for my little R2D2 this week. I'm sure you can understand how exited I'm to go to the barn now !

I received the following :

- new honing tool 320 grit, 3 inch bore (approx 76 mm, for a 78 mm cylinder bore.)
- new clutch assembly with pressure plate, and release and pilot bearing,
- new piston rings set (3 of them)
- new crankshaft bearing set
- new sit ! (yeah, the old one was just a piece of sheet metal !)
- new glow plugs
- new complete engine gasket set (oil pan, head, intake, exhaust, valve seals, and valve cover)
- lapping compound

This week end, I'm going to start splitting the tractor and clean the head / removing the valves. I figured I'll split it now that the front end is lighter since the engine is all taken appart.

A lot of fluid will be drained this week end ! And elbow grease will be at work.

Any tricks from somebody that had split a similar tractor before I jump in ?

I have bottle jacks, a big floor jack 3 1/2 ton, some jack stands, even some heavy duty dolly. Some 1/4 ton come along, a one ton come along, and a 2 tons chain hoist.

Hopefully it should be good enough. I'm far from any store, so I'm trying to be very ready before I start on the job.

 

[bnjleouf]

Wife got me some honey does this week end, but I still got the dashboard out, and the front end loader off the tractor. ( which was a pain in the @#@#%$# being alone !)

Took the valves of the head as well, everything looked good, and valve seats were shinny and clean which is a good sign.

I could hone the cylinders, which came out pretty good as well, not the best but far from what it was.

Pistons are ready to slide in, and are stored nicely just waiting for prime time !

I'll be working on it all next week since I took some time off, so I should have it looking mechanically good !

 

[bnjleouf]

Well, little heads up here,
I put this thing back together, had it splitted, and fixed the clutch (the release trolley was placed in between the forks for some obscure reasons !) and put the engine back together.

I get 260 PSI on each cylinders.

The tractor has the hardest time to start, after preheating three times, it starts, but you can feel something is not right.

I think my compressions are way too low.

I got it running, and left it idling to warm up, it does runs good, you can move around with no problems. But it is not quite right unfortunately.

My compression problem may be coming from the head though. When I lapped the valves, I noticed some damages on the exhaust valve sits, like corrosion. it is very possible that my head might be porous.


I have fuel going to the injectors, diesel pumps seams fine. glow plugs are new, water pump new, new rings, valves laped, new head gsakets, torqued right...

Any inputs ?

 

[bnjleouf]

Or might it be a timing issue ? Who knows what happened to this poor thing before I got it... I might need to check that out.

 

[shinnery41]

If you did not hone the cylinders the new rings may have problems sealing and that may be the cause of your low compression.
Bryce

 

[bnjleouf]

Thanks for your input Bryce,

I did hone the cylinders with a 320 grit honing tool. They were smooth to the finger all around.

The only thing is I had a ridge on the top, but it didn't prevent me to remove the piston or putting them back in.

I might pull them off again, just to see what's going on.

 

[MT2501owner]

Hey neighbor, did you get your tractor running like you want ?
I have a 2501 also and keep toying with the idea of rebuilding it, but most of what's worn out or broke is tractor drive train or frame items.
It needs front final drives and a steering box. Exhaust manifold is also cracked. Motor and hydraulics are strong so I feel it's worth a few bucks to fix the rest. It's also manual steering and if I could upgrade that it would definitely be a big plus. Don't think it needs to be split, but it needs just about everything else.

 

[bnjleouf]

Hey there ! Good to know another Mitsubishi owner is living close by !

I live in Houston, spring branch (no room or need for a tractor here !), but my country place is out towards san Antonio in Gonzales TX.]

I would say that your MT2501 is definitely worth the money you'll put on it.

The front drive can wait, you just have to de activate the 4wd at the beginning. The steering gearbox, I just changed it on my international, which is made by Mitsubishi as well, and looks identical to my Mitsubishi. It is not hard to do, and the gearbox is really easy to find (kind of pricey, but I got the best price on ebay)

Now, my tractors are a little smaller than yours, but the international is manual steering, and the MT250D is hydraulic. Honestly, the manual steering is not a problem on that size tractor. I don't know if it would be worth upgrading yours, knowing the hassle it can be to fit the hydraulic one on a manual tractor.

The exhaust manifold can be welded or brazed, if you know a good welding shop that can help you.