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Mastiffman

3 Cylinder Kubota vs 4 cylinder Mitsubishi Diesels?

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I'm looking at a Toro Groundsmaster and I'm not sure which one of these engines it has in it. 

 The unit model is a 325D.

 Probably would depend on the year and serial number?

 SO it looks like the 322d and 325d only came with the Mitsubishi 3 cylinder, not four and the 328d came with the Kubota 3 cylinder

 

Edited by Mastiffman

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I work at a kubota shop and these little diesels are great and I believe not much has changed and plenty of parts are available from kubota. I Allso own a 1989 Cub Cadet 1772 wich has a kubota D640 (17hp) 3 cylinder diesel, runs perfect and has remarkable amount of power most comparable to a opposed twin but wont bog down as much and uses much less fuel.

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Excellent! 

 

 Thank you. The one I actually brought home was from a 93' groundsmaster and it's the 3 cylinder Mitsubishi K3D diesel... 

 

Runs great! No smoking mostly. Only at WOT and it will give what sounds to be a slight "miss" and then a small puff of blue/white smoke. But only at WOT... 

 

I did notice after running if for a bit that it had a small leak around one of the injectors... Could this be the reason for the miss and quick puff of smoke? I will get a video today and post it up. 

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I have Yanmar, Kubota and Mitsubishi engines and have had excellent luck with them. The more common models from these manufacturers will all have good parts support. 

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Excellent to know. Thanks!

So any idea what could be causing this slight "miss" sound at WOT? Like I said, it gives a slight puff of smoke each time. I didn't have time today in the light as I cut my next door neighbors grass and I let the leaves go to long and had to make a couple of passes over the half acre to grind those leaves in well. ;) 

 I will be getting video tomorrow. 

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Could be several reasons but the most common cause would be a dirty injector. You could start by running an injector cleaner in your fuel. I have a Yanmar in my Golf cart that does that on occasion so I run a little Marvel Mystery oil in the fuel and it runs like a top. You could take off the line to the leaking injector and see if it is cracked or the matting surfaces need go be cleaned. You will have to purge the air from that line before running it again.

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Excellent! I will do both of those today.... Thank you very much. 

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I use the "Power Service" brand of diesel fuel supplements (white bottle) injection cleaner + cetane boost all in one plus they make a winter version (silver/gray bottle) that helps eliminate water/gelling and an "emergency" type in a red bottle with concentration of cleaners ect, I use the white and gray bottles in my new Mahindra and older Kioti diesels it does help with quieter running and less black exhaust during operation, again just my personal experiences, Jeff.

Edited by WVHillbilly520H
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Okay so here is the video of the engine running. now sure how well you'll be able to hear the miss. but you can see the puffs of smoke. 

Check out that hour meter!? wow. Read that the Mitsubishi are good for 8000hrs if cared for. This one was supposedly built 1000 hours ago by Carl Sweeny...
 

 

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Please please don't stick your hands under that deck again with the engine running. :( 

 

Does the engine miss more under load? 

I would say the whole fuel system could use a cleaning. Who knows how old that fuel is. Can you rig up a small tank with fresh fuel and see if it runs better. I didn't hear anything of concern other than the slight miss. 

I think that mower might have set a record for most hours and still running. :)

The reason for the heavy steering could be the hydraulic oil. From your description it sounds like it is way too thick.

Edited by Cvans
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I understand safety and the mechanics of how it works and the lever needs to be forced forward to move the pulley and then tighten the belt that engages the blades for them to be a danger. If you watch the video you will see that I loosened the blades with the mower at idle and the lever in the safety "off" position and then hopped back on and then engaged them.

If was safe don't worry. I'm not an idiot that going to ever be willing to put one of my arms in or anything in jeopardy but thank you for you concern. lol In fact I actually have a bad habit of imagining the worst thing that could happen at times. smh. Might be a benefit though. 

Yes, the engine does miss mostly and only under WOT. I couldn't tell if it was missing when the blades were running because those bearings were roaring.  The fuel looks nice and blue toned inside. not sure if that's an indication or not. 

I could rig up a small tank and check. Could there be an issue being caused from the leaking around that rear injector?

It was Carl Sweeny that rebuilt the engine 100 hours ago. So ' being told that the engine only has 1000hrs on it. The rest of the machine clearly shows a neglected 8284hr... :(

Yeah I agree with the steering issue. 

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If the connection at the injector is just damp it shouldn't be much of an issue. If it is dripping than yes it can cause problems with that cylinder. 

All you need to set up a temp. tank is a small tank off of a push mower and an inline filter. 

 

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Okay, so I used some engine cleaner and my pressure washer to clean this thing up. Was nice to be able to see everything and I made a couple of discoveries about at least one leak and other stuff.. There is a dent in the valve cover by an engine hoist bracket. It has a tiny crack in it and is leaking a smidgen of oil.
20171115_111249_HDR.jpg

Here is one of the things that I found... 
 



Now the engine seems to be smoking more than before!? I did put more oil in crank as it was low... So as you can see I'm not sure if I need to switch out the fuel as the moving around was mixing it around in the tank causing something or if it's the injectors which I'm not sure why it would smoke more after washing it. So at this point I'm not 100% sure what it is. 
 
Does this thing need rings? Supposedly it was rebuilt by a well known diesel guy they said. Who knows if that it true. Seems to be having to many issues at this point. 

 You wouldn't think that a professional engine builder would puncture a hole in the valve cover. smh... 
 

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Find the crankcase breather tube and see if there is a lot of blow by coming out of it. You should be able to hold your finger over the end of it for a little bit without building pressure. If it wants to push your finger off right away your rings are worn, broken, or never seated. 

I notice in this video that that the hose clamp on the injector bypass hose is off of that wet injector. That might be where your fuel is leaking from. 

Nice find on your hydro. Had to make your day. :)

Edited by Cvans
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I will try that with the breather. I was going to remove the injector and I took that clamp off and didn't put it back on before recording the video. So before it was leaking with it on. 

 

 Yes it did! 

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I'd look into that breather first as Cvans mentioned - if it doesn't have a ton of blow by you might want to have those injectors serviced . With the trans in that good condition I'd consider putting it in service - you could mow that yard in 5 minutes...lol .

 

Sarge

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58 minutes ago, Mastiffman said:

Yes it did! 

 

Leak or push your finger off the breather . I personally like Lucas brand oil / fuel additives/cleaners products. Hot Shot stiction eliminator will also clean out your oil and fuel system/ejectors. If need be I know a place that can test your injectors ;) .

Edited by ACman
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The breather goes from the valve cover to the intake manifold. It's not loose. Should I take it off and follow the procedure and will I still get the same results, good or bad? And if I can do that, should I plug the intake manifold nipple that it's attached to during the test?

Also, if I put engine oil in that wasn't rated for diesel, would that get too thin and seep past the rings and cause the smoking?

Edited by Mastiffman

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Okay... So here is what the fuel looked like when I drained it... WOW... 
 

 

Here is the result of the new fuel. Not much difference... 

 BUT, I pulled the breather tube off and there was very little air coming out of the breather port on the valve cover at idle nor at WOT....

 Tomorrow will be testing the injectors, compression and changing oil and filter. 
 

 

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Alright... 

 So after a bunch of work today I was able to pull the injectors off one by one and get a test on them. They all seem to be working correctly. But when I got to the last one after having to remove the bottom port that screws into the injector pump, I wasn't getting any pressure but the injector looked to be working as it had a shiny spot where fuel would be coming out. So all three were cleaned. I tested the glow plugs, they were fine. I had to bleed the system a couple of times and by that time the battery was shot. So while charging the battery I did a compression test with my cheapo HF compression tester. Which only goes to 300 psi. 

1st cylinder seemed slow to build up to about 370psi according to the distance past the 300 mark that the needle traveled. 
2nd (middle) cylinder was a very quick high compression of over 400psi according to the same distance theory. 
3rd Cylinder also was low at about 275psi. So now wonder why it was so hard to start. 

 But I don't understand why there wasn't much blow by in the breather tube on the valve cover. Also why it idles perfectly once started... Unless my Cheap HF compression tester was giving me crap readings. 

The manual states that all three cylinder should at least be within 36psi from one another. So it looks like either the person rebuilding the engine didn't know what they were doing or I was lied to about it being rebuilt. I tend to lean towards the later with the leaks coming from what looks to be the rear oil seal... and oil pan. So looks like it will be put away for the winter (or until I get done with other jobs and bored) and tore into next spring. 

 Hoping that it;s just the rings and hone job along with oil seals and new gaskets. 

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In your situation I would do some research on the matter before making the purchase. That's going to be a lot of work just to find out you purchased egg shaped rings. Can you talk to the re-builder and  find out what he used for parts?

 

 

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So you've heard of Chinese rings being out of round? Or did I read that wrong...

 

 I don't think that it would be too hard. just one more than an Onan. 

Edited by Mastiffman

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So you've heard of Chinese rings being out of round? Or did I read that wrong...

Only once.  I don't recall if the cylinders were checked or bored before the install. Just saying if it were my money I would investigate a little before making the investment. I might be inclined to tear down the engine and inspect it prior to making a decision on how to proceed. 

 

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