Problem With Mini Excavator?

woodchuck2

I hope this is the correct place to post this, i am having a problem with a shorted wire in my mini-excavator that causes it to shut down and not restart. I bought a parts manual for it from Dominion Equipment but i have not been able to find any kind of service/repair manual. I bought this Sumitomo SH-38 used and it has ran great until now with the exception of an alternator. It is now blowing a 25 amp fuse so i began to diag it but it would be much easier if i knew what the circuit is for. As of now i have the floor plate out of it and have tested the wire to where the harness goes behind the engine which i cannot even see no less feel. I wiggled the harness and it is still shorted to ground so i began removing the plates under the engine/counter weight to gain better access but stupid me had to park the counter weight over the blade . Now of course there is several feet of snow too so my rather large physique isnt going to be very compfy working on this pile. Looking for some knowledge of where i might be able to purchase a service/repair manual for this lump.

giannid

The Sumotimo brand is a grey market machine so you will not have any help from a Sumitomo dealer. They are the same machine as many Linkbelts and case mini's. I would try and find out which Case or Linkbelt it is the same as and go from there. I had a Sumitomo which was the same machine as a Case 9070 and the Case dealer worked on it for me. The service guy gave me an ass ache but the tech who worked on it told me it was the same exact machine. Also, you may still be able to get an english written manual because I know they sell the Sumitomo machine in English speaking countries like Austrailia. Hope this helps.

tgeb

giannid knows more about this particular machine than I do. I googled it and the first link came back here.

In general, electrical problems can be one hell of a bitch to figure out. However were it my machine and it kept cutting off I would be suspect of the solenoid in the injection pump that allows it to start and run in the first place.
A jumper wire to that circuit would be able to tell you if that is the problem or not, and if not the jumper should let you run the machine enough to get it indoors or on a trailer so you can get it in the shop.

A 25 amp fuse is a fairly large fuse and leads me to suspect the alternator replacement could be the culprit. Check the lead wires to and from the alternator and be sure one of those has not been grounded.
Could be the alternator itself and possibly this could be tested.

I wish I could be of more help but....

Good luck with it, post back if you find anything out, let us know how you do.

__________________
Tom

www.gebcon.com

cdub

Big hammer might do the trick.

__________________
"The beatings will continue until morale improves."

tgeb

That has been known to work......sometimes.

__________________
Tom

www.gebcon.com

cdub

And here I thought I was just injecting a usless comment into a focused conversation.

__________________
"The beatings will continue until morale improves."

dayexco

might be something wrong with the computer? can you switch it to manual, override the computer?

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someday, i'll be as patient as Nick.

woodchuck2

I bought the parts manual from Dominion Equipment and i got in English, took 2 months to get it and cost $140. I suspected the Alternator from the get go, it ran fine but wasnt charging so i sent the Alt. out and had it rebuilt at the tune of $170. Put it on and it only put out 12.3V at WOT and would drop to 11.2 at idle. I put a new battery in it with no change so i sent the Alt. back to be checked. They put a new regulator in it and it still didnt charge. By then i was pissed so i pulled it and modified a GM Alt. to fit it and put that on, the wire harness for the Denso Alt only used two wires, one is the signal wire from the PCM which i also used on the GM Alt. It now charges great. During this time it started blowing fuses. I have already replaced the fuel shut down solenoid thinking that was a problem but it still pops the fuse and now it is to the point it wont start. I was told it was a grey market machine, i will have to check the other makes to see what is the same. It does have an Isuzu engine and cat controls.

woodchuck2

I have already wondered if it might catch "fire" from the short and burn up. I wouldnt think twice of buying a new one right now. Next one will be a Kobota, the dealer is onle 30 minutes from me and they are reliable machines too.

woodchuck2

I did a little more research and you are correct about Case, from what i read Case bought out Linkbelt along with a portion of Sumitomo and several other brands and they now have an alliance with Sumitomo. I joined another site also to see if i can get more info, it is Heavy Equipment forums.com so hopefully i will find something there too. Thanks for the info so far and hopefully someone else will reply with more info.

cdub

When you say it doesn't start do you mean it does nothing or turns over but doesnt run? I had a computer go haywire in a machine before and it would do all sorts of goofy stuff (not start, start at high idle, start at low idle w/no throttle response). It would work fine on manual override.My brother came up with some sort of code to reprogram the computer. It would work fine for a few days or a week then mess up again. We did this at least a couple of dozen times then the batteries went bad, we changed them and it has worked fine ever since (probably three years).
You may have a computer problem. I wouldn't bet it will fix itself. If it doesn't, try a bigger hammer.

__________________
"The beatings will continue until morale improves."

woodchuck2

It popped the fuse once before and it had quit, replaced the fuse and it fired right up. When it blows the fuse the glow plugs still come on and it will crank, just wont start. Starting fluid will let it run for a few seconds but i dont like using the stuff. It seems to me to be an electrical/fuel issue. I am 100% sure if i can find the short and repair it then it will run properly. I traced the wire to a plug at the main valve body and have determined the short is behind the engine. The problem is the circuit branch's off at the plug and i cannot find this same color wire anywhere on the engine. If i just knew where the circuit went then i could try to bypass it enough to get it running so i could gain better access to properly repair it.

cdub

Don't let me insult your intelligence, but are you sure your getting fuel to the injector pump? I've often confused a problem for another, unrelated one. From what I know about deisel engines, if its getting fuel it should run. From here I would guess your short has something to do with the shut off solenoid. I'm not sure whether it needs power to be on or to be off, but if you have fuel at the injector pump and you get creative with a jumper wire I'd bet you could get it running temporarily, or burn it up. Its a win win.

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"The beatings will continue until morale improves."

woodchuck2

I have fuel to the injection pump and it will run on starting fluid. I havent tried jumping the fuel shutdown solenoid because i just replaced it thinking it was shorting out. I tossed the old one already and i hate to burn up the new one, damn thing was $180 and took 6 weeks to get it.

tgeb

I have been curious.

Have you figured out what was wrong with this thing, or is it a piece of Yard Art?

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Tom

www.gebcon.com

woodchuck2

The damn heap is still buried under all the snow, i am contacting a Case dealer tomorrow to see if they can aquire info. Until then i have to wait for this snow to melt so i can crawl my fat a55 under it. Damn thing is becoming a thorn in my side, i have jobs lined up for it once the snow is gone so i have to have it running. Thanks for checking in, i will post again after i talk to Case.

woodchuck2

Well, i talked to 3 different Case dealers with no luck although they did try their best to help me. I was talking to a friend of mine who is only 21 years old and ya know what he tells me? He tells me that this happened on his Bobcat with a Kabota engine and all he did was remove the fuel shut off solenoid and it started. He said it will not leak fuel either since the solenoid only pulls and pushes on the fuel valve inside the injection pump. He also said the solenoid pulls the plunger away from the valve when the engine cranks over allowing fuel into the injection pump, when the key is turned off then the plunger pushes the valve closed blocking off fuel to the injection pump. Once running the only way to shut it off is reinstall the solenoid. So once it warms up a little then i am going to try this, if it works then i can spin it around for better access so i can repair it properly. He is a young fella but i hope he is right, it makes sense to me.

tgeb

It does make perfect sense, though I must say I have never had one apart, the way he described the function is how I would expect that system to work.

Give it a try, the snow has to be gone by now, it was nearly 70 here yesterday.

__________________
Tom

www.gebcon.com

cdub

If you can't get it started give me a call. I'll bring up a quart of whiskey and a great big hammer and i'll help you "work" on it. We'll tell your insurance that your competition got you.

__________________
"The beatings will continue until morale improves."

woodchuck2

Thanks guys , we still have about 2.5'-3' of snow yet, snow banks are down to 5'-6'. It is 12deg right now, hard to say if anything will melt today. I will keep posting with my results.