D722

[Workerbee]

Hi, I was looking at a 3 cyl D722 engine in a genset. It will start momentarily but then die right away, according to its owner. By photos it appears pretty clean, but I havent looked at it in person yet. He has no idea how many hours are on it either. He took it out of a motorhome where it had been abreplacement for the original generator.
My questions are, whats likely to be the reason it dies? And what would you think a value range would be?
Thank you

 

[BigG]

Check the air filter is clean and more then likely the fuel needs drained and replaced with fresh fuel and a new fuel filter. Add a fuel dryer to get any condensation out of the tank. Also dose it with an algicide to keep the fuel clean.

Not enough info for a value judgement.

 

[Workerbee]

Thank you for your help. I probably could have worded my questions better!
I havent been near it to check anything. Im just relaying what the owner told me about it, and I dont think he knows any more than this. I think your advice on whats likely the reason it will not stay running is spot on (fuel related) but I cant or dont care to do a lot with it unless I owned it. I also was thinking it could be something involving the genset shutting it down, but wouldnt know unless I bypassed the controller.
So as far as value, what would anybody think its worth in the condition I described with unknown hours and unknown running problems?

 

[greenacresnorth]

could also be the Murphy switch tied to oil pressure, either engine has no oil pressure, pressure switch is bad, wiring is bad between switch and pressure sensor or the murphy switch its self is bad.

 

[PaulL]

The problem is that its worth is somewhere between zero (or negative, by the time you spend effort to discover that it's not fixable at a reasonable price) and maybe a couple of grand. If you're confident that he hasn't attempted to fix it, then there's a reasonable chance the issues are minor. But equally he may have investigated and discovered it requires expensive work to fix it.

Personally I'd pay a couple hundred dollars for an engine in that condition, and then only if:
a) I had a use for it once fixed
b) I had time and enjoyed fixing things
c) I was OK that I might spend a couple hundred dollars plus some time and parts, and discover it was never going to work

In other words, it has no real value, other than as a hobby project. Or I guess as spare parts, if you had another D722 that needed spare parts.

 

[North Idaho Wolfman]

More than likely It's a bad fuel stop / run solenoid... or the wiring associated with it if it's equipped with such (kubota actually uses three different styles of fuel stop / run coils).

If it's a 2 coil solenoid:
One coil to pull it in, so it will crank and start.
Second coil which is the hold coil is the one that keeps it running (this is the part of the coil that is bad).

 

[Workerbee]

Thanks for those great tips on possible causes. Each sure is a possibility. I never thought there may be two solenoids on the pump but it sure makes sense.

And Paul thank you for laying out your idea of value. I doubt he has messed with it, but then inly he knows that. I do enjoy working on engines and thats the reason I wanted this one. No immediate need, but Im sure I could come up with a use for it. His asking price is $1000 and I told him that its a bit much for something not running. So he said to come look it over and make an offer. I was thinking if things looked ok and no signs of wrenching on it that itd be worth 5-600 but kind of thought I might be too tight on that. Im happy to see youre tighter yet lol. And yes I agree with your reasoning. Thank you.

 

[coachgeo]

my bet is air leak and/or algae.

 

[Workerbee]

Also I do have a D782 in a ZD21 and I think some parts would interchange if it came down to scrapping it for parts.

 

[PaulL]

I was thinking if things looked ok and no signs of wrenching on it that itd be worth 5-600

Probably fair. To me it's the difference between having a definite use for it (i.e. you'd otherwise pay $5K for a new one), or buying it just because. If the latter, then it needs to be a bargain, because if you spend $500 and then $500 getting it running, you've got a $1,000 engine you don't have a real use for. If the former, then yeah, if you paid $500 and then spent $500 fixing it, you'd be well ahead compared to paying $5K for a new one.

Flipside, for him at the moment it's a lump of metal taking up space. $500 is a lot better than a waste of space. If nobody else wants it, he'd just be happy to be rid of it. Sounds like he'd have no use for it if it was running anyway. $500 sounds fair, but really comes down to how tight for money you are personally, I suspect you could screw him down more, but if you don't need to then don't.