I'm looking for help thinking my way through a problem. Mitsubishi grey market tractor from the '70s. It has a 2 cylinder diesel, KE95, makes about 22 hp (supposedly). It's all mechanical. The only wire on the engine is on the glow plugs. I haven't checked compression yet, but it fires up quickly and idles nice. Injectors both crack at around 1700 psi, which is spec, and give nice chatter, and mist, and don't leak. Cylinder head just got a new valve job, and decked. New head gasket (of course) and just re-torqued today. It runs great up to about 1500 - 1600 rpm, when it starts to bog and spit white smoke. If I push it, rpm doesn't go beyond about 1800 (redline is around 2500), and it's missing and spitting until I throttle it back to about 1500, where it likes to be. Both cylinders doing the spitting and missing. I ran it with the exhaust manifold off, and watched it. No leaks. No coolant loss. No blowby (I was watching that too). Also ran it with an aux tank, no change. I'm open to suggestion.
Sound kind of timing related to me. Does the engine have some kind of timing advance?
No, it’s geared internally and otherwise fixed. No adjustment at all, as far as I can see.
Do you know if the cam was checked?
My first thought was timing related. Are you certain the copper nozzle gaskets are the correct thickness? How’s the valve adjustment? What a cool little engine.
No engine internals have been out, as far as I know.
Good question about the injector gaskets! Not sure. I’ll pull them tomorrow and have a look. Overheads just done. That damn engine is a unicorn. There’s a couple variants that are more popular like the KE70, KE75, KE130… but this 95 is a real oddball. My first time messing with one.
I thought timing too, but air in the fuel is easier to check. Put the fuel return into a clear hose or into a jar to see if there's any bubbles. Or check the fuel supply.
Is the fuel good? No water, not old.
My TL150 machines will do that with a fuel supply deficiency.
There is almost no return from these injectors. Maybe a tiny drop at full throttle. Fuel system is gravity feed, and I’ve tried an aux tank and lines as well, in case the existing tank and lines were bad.
Fuel is brand new. No water.
With the white smoke too? That’s the part that’s actually throwing me off. I’ve never seen a starvation situation with smoke. Smoke always means something else. Others have suggested a timing related issue, and that makes more sense to me.
Purge the fuel system? Just trying to get a grasp on what you're working with.
I definitely appreciate it! Yes I bled as much as I could. I guess it’s possible I still have air in the system, and I just need to run it until it all gets out.
Gravity feed to the injection pump or to the lift pump? How old are the lines from tank to filter and so on? Is the tank rusty inside? Do the hoses crack when you bend them? Does fuel dribble from the tank bung or does it pour?
Gravity feed to the injection pump. No lift pump. All lines and filter are new. Tank is clean, and flow is good. I also ran it with an aux tank held up higher than the regular tank, to assure good fuel delivery, and got the same result.
Put a electric fuel pump on it, probably even carb style might work.
I would introduce an inline pump to the filter( a cheap diaphragm pump for testing.) I'm guessing that the filter, while clean and new may be more restrictive than when it was manufactured. Additionally, i would make sure the tank is properly vented. Maybe leave the cap off or loose. Verify that your fuel hoses didn't get pinched or kinked anywhere. Is this engine naturally aspirated? Is there a fuel return?
What I’ll try tomorrow is, bring the engine right up to the point it starts to stumble, and use shop air to pressurize the tank a little, and see what that does.
Autozone has a 12v electric pump for $30 that I used for testing fueling issues, coworker had a boat fuel tank set up for the same. The pump makes a big difference, suction can't keep up with demand.
So, I did have an extra gasket under one of the injectors, so props to Coaldust for catching that one! Slight improvement, but not there yet. Starts a little easier now, that's for sure. But this would tend to indicate I'm looking at a timing issue. Trouble is, the company that knows these tractors best, just went out of business because the patriarch passed away. I'm starting to wonder if my tach is accurate. According to my tach, I'm idling at 500, and I'm told these engines don't idle below 800. So, if my tach is reading low, maybe I'm getting alot closer to redline than I thought. I'm going to put an optical tach on the crank and see what's what. I did pressurize the tank with shop air while the engine just started doing it'd stumbling thing, and no change, so I don't think it's a delivery issue. Haven't ruled it out yet though.
Direct or indirect injection? I had a Chinese built Cummins indirect injection that had removable, round, combustion chambers in the head. The head was sent in to be redone and the machinist did not put them back in the head. I was in a hurry and didn't notice it. It started and ran great but when the RPMs got to about 3/4 throttle it started to spit and sputter and smoke.
IDI, for sure. I believe those round things are called prechambers, and yes this little cracker has em. They're in there though. You can actually see them through the injector holes.
Good to know, it took several different Cummins techs to help me find the problem. We all need to be humbled on occasion.
If it's getting starved for fuel, wouldn't the spray pattern go to hell? Also, do you know if the injection pump is working properly? Has this engine ran fine before, and now it doesn't?
It would imagine so, and that would generate smoke, I would think. I'd just never seen the smoke in relation to starvation. Of course, you could fill a big bus with what I don't know, so that's not saying much. I was told that it used to "run great". That's all I know about it. This is a machine I took in on trade against an invoice that was owed. Sometimes that gamble works out, sometimes not.
What are the effects of setting injector opening a few hundred psi higher? Timing would change a little maybe, maybe a better mist? I have them at about 1600 now. I wonder what would happen if I put them up to 1800-2000. I wonder if I even could…
I missed this thread, here is another vote for fuel starvation. I presume it has the little chunk of an IP mounted down in the block running on the cam shaft? Have you tried a lift pump yet? Partial fuel starvation will cause sputtering and intermittent smoke and misfiring, seen it many times. If you rev it to max RPM does it run clean for a second before it starts stuttering? That would indicate the fuel starvation. Otherwise I am suspecting some kind of stickiness or something like valve float inside the IP when RPM is too high for everything to work like a clock.
I may have missed it, but I'm just curious if you've checked the air filter. White smoke can happen when there's an air restriction as well.
The timing on that fuel system design is adjusted by a shim pack underneath the block containing the injection pumps, which sets the distance above the fuel lobes on the camshaft. Could someone have had that block off and changed the shim pack in any way ? Fuel delivery amount is adjusted by rotating each pump. They are set to deliver equal amounts of fuel to each cylinder’s injection valve. You have to be careful to not let them turn as you remove the injection line. Restricted air supply can cause an issue, too. You would expect a lack of air (too much fuel) to cause black smoke, but several times I have run into an engine that ran like a bag of crap at higher rpm’s caused by a choked up air filter and smoked gray, almost white. Stumbled, popping and banging. Like a late JD 4020 with a dry air filter and a secondary air filter up under the hood, on top of the primary air filter housing, that nobody knew about. OOPS, sorry, Mater. I didn’t see your post while I wuz typing. I had to get more coffee and missed your comments. Odie
Air filter is new. Engine does this with or without air filter. As far as I can tell, nobody has taken that pump off. No tool marks on the bolts, paint all intact etc. I’ll take a closer look though. I didn’t see any adjustment on the plungers. I have an S3L here in the shop too, and it’s similar; you can see how the plungers would adjust. On this KE95, I don’t see it. Again, I’ll look closer. You’ve had some experience with this engine?
Might this be a Satoh?
Close! Mitsubishi D1800(2)
Not on a Mitsubishi, but that is a common Bosch design, probably the tag says Diesel Kiki, used by many mfgrs. I’ve worked on Yanmar and Kubota engines that are of that design. Very simple and reliable and almost trouble free. Why was the head work done on this ? Was it like this before the head work, before you got the job ? Turbocharged with a stuck wheel ? Or a rag in the intake ? I hope you find something simple.
The head work was done because the original head cracked in both bridges and I sent that head to 3 or 4 shops, and they all told me it was not repairable, so I found a junkyard head, and sent it to get decked and magnafluxed and all that.
The injectors are ND (nippon-denso I assume).
What was used to determine the head was exactly the same? How about parts? Are the valve springs right? It's not floating the valves, is it?
I have seen a fair number of small engines where the valves returned, but slowly. But this was cranking over at hand speeds. I wonder if this could be a problem on this unit, valves not closing quick enough above a certain RPM. Sort of like valve float but due to gunk in the guides. Crazy idea I know but all the good ideas have been used it seems.
The head is identical to the old one, that’s all I can say there. The work was done by a shop I trust, so I have no reason to doubt their work. I do have the original set of springs I could put in.
There’s nothing I can rule out at the moment, so no crazy suggestions yet . I can’t imagine float at under 2K rpm, but granted, that would fit my symptoms. Maybe I do need to take a closer look at the head.
Restriction in intake, and pulling air thru crankcase, hence the smoke. Wild thought
So I thought I’d go to the shop this morning and play with the injectors. I’m not a fuel system expert, but some stuff I had read suggested those injectors should be cracking at 1800 not 1500. Shortly after I got there, I got a call from my wife who was singing at local service. Some a$$hat stole her catalytic converter! Right in broad daylight this morning. Are you f@@king kidding me? The super crappy thing is, if we decide to let insurance pay for it, there’s a good chance they’ll total the car. The cost to repair at the dealer is around $4K, and the car isn’t even worth $6 on a good day. Of course, I’m going to do the work. I had to stop, go home, grab the trailer and go get her and the car. She’s fine and the car’s in the shop but what a dang pisser. WTH is wrong with people anymore? Anyhow, this tractor is on the back burner until I get the car fixed up. I’m going to try to attach a pic of the lil guy.
I can't like that it sucks!
Sorry that happened-thieves are brazen as hell, last spring a two axle car trailer was stolen a block from my house in the middle of the day taken from a driveway while a birthday party was going on in the back yard.
Just since I posted the above 41 minutes ago the boss calls me. {Do you have a file on the 2021 GMC office pickup?} No I don't, what's the problem? {That new driver we tested Saturday--I gave him the pickup to run back to Caldwell ID to pickup his stuff and come back. Well he was caught on video at Walmart shoplifting, the police lost him in a chase, I need the vin# for OnStar to find the truck.-------------------------------------------------------- --------------------------------------------------------------------------------------------------------------------------- I can't help it I got to laugh-lol,lol,lol,lol,lol,lol.
WOW
INSURANCE! the insurance policy will have the VIN!
Well at least you know he's a talented driver if he shook the fuzz.
He and vehicle was found, he got a free ride back to Idaho. Warrant for breaking and entering, domestic abuse. Just the garden variety criminal that's trying to hide from the law in a OTR, happens a lot BION.
Well alrighty then, I had to mothball this project for awhile, but I’m back at it: I got a chance to piddle with the injection pump this weekend. I needed space at the shop, so I brought the little tractor home. All I’ve really accomplished is, I’ve eliminated the pump itself, and put it in a good position to adjust timing a little to see if I have a fuel timing issue. All I have to do is take out one of the 3 gaskets that are now in there, and see if that makes a change. One of those gaskets at .015” should be good for almost 4 degrees of timing. That should generate a noticeable difference. If not, no matter how unlikely it seems, I think I really am looking at a valve floating issue.
Whelp, got some closing notes for ya. Since the pump refurb, I was back to it falling on its face at around 1500 rpm, fully suggesting messing with the pump was not necessary. So today I pulled one of those 3 gaskets I made, just to see if I can make a change. And change it did. I believe each one of those gaskets was worth 4 or 5 degrees maybe? Anyhow, now it runs smooth up to 1800. So those 4 or 5 degrees was worth about 300 rpm. I do notice a little more clatter at idle, and it starts easier as well. But it seems to be happy with the change. I’m hesitant to take out another gasket, because I don’t want to hurt the little guy, but I’m real curious what a few more degrees would do. Anyhow, not a head scratcher anymore, it was all down to a timing issue. Thanks to everyone to tried to help. Much appreciated!
I may have missed it, did you do the spill port timing procedure to find out what the timing is actually at?
No, I didn’t. Reason being, I don’t even see any base timing marks on the engine, and no good data is available for it. The manuals that are available are copies of copies and the quality is quite poor. So you pay 60-70 bucks for a book that looks like an old mimeograph document. It seems to like the timing where it’s at, so I’m thinking I’m going to leave it. I don’t want to advance it too far.
If it was mine, I might have made my own marks and done it anyway just to be able to know where it is at. But I did replace the injection pump on my old 6.9 Ford and just set it where it seemed good and it ran hundreds of thousands after that.
Glad you got that off your back and mind
One more “final update”. Yeah I know I said the last one was the last one, but this really is. So after some more messing with it, I just didn’t believe my own BS, so I checked the tach. I put a photo tach on the crankshaft pulley. Little piece of reflective tape on the nut, actually, and was able to get a stable read. As the mechanical tach inidcated 1500, the engine was actually turning closer to 2500. Indicated 1000 was closer to 1800, and indicated 500 (idle) was closer to 900. So, indicated 1500 was actually pretty close to redline, and I shouldn’t have screwed with it AT ALL! Ugh. I did manage to learn a lot about these pumps, so not a total loss, but a giant PITA, to be sure.