Alternators

[jellybean]

Need a bit of help please. I have an old Kubota KH90 digger that has been giving problems. It is now charging at 16-17 volts and cooking the battery. I cannot find a voltage regulator anywhere. It did have a new alternator maybe 4 years ago, would there be a regulator incorporated in there?

Its other problem is the engine keeps dying. I have had the mechanical fuel pump rebuilt and the injectors done. It did a couple of days work after that and went back to its old tricks of dying. It will usually start again but only run for a few seconds. Occasionally it will run long enough to track about 20 yards. Fuel tank has been drained and flushed as best I can, filters have all been renewed. You would think its not getting enough fuel but I cannot think why. Any help grateful accepted.

 

[flywheel]

What make & model of alternator.? Back in the days early 80s, renault 18 had regulator bolted on the end... Fryed itself every 6,000 miles...

 

[box]

Photo of alternator required.

Fuel tank not venting correctly? Mechanical fuel pump still playing up? Injector pump problem? You're going to have to do a bit more investigating when it plays up and find out where the fuel's gone. Clear hoses, pressure guages, an external temporary fuel tank gravity feeding to injector pump etc.

 

[jellybean]

What make & model of alternator.? Back in the days early 80s, renault 18 had regulator bolted on the end... Fryed itself every 6,000 miles...

Photo of alternator required.

Fuel tank not venting correctly? Mechanical fuel pump still playing up? Injector pump problem? You're going to have to do a bit more investigating when it plays up and find out where the fuel's gone. Clear hoses, pressure guages, an external temporary fuel tank gravity feeding to injector pump etc.

Temporary tank sounds like a good idea, if it runs ok with that at least I know it isn't the refurbed pump and injectors.

 

[rob h]

possibly stop solenoid over loaded by the high voltage?. I would get the alternator fixed then see if it cures the cutting out

 

[clbarclay]

All the filters? Some lift pumps have gauze filters in them as well as the main fuel filters. They can clog up too.

 

[Highland Mule]

Filter built into the tank outlet point too, on some. That’s been the cause of trouble before on a tractor of mine.

 

[zero]

Our Kubota compact tractor has a separate regulator box bolted under the bonnet. It used to fry batteries till i discovered it could be adjusted. I did accidentally touch two contacts at the same time which stalled the engine it charges normally now I've got it set up properly though.

 

[jellybean]

possibly stop solenoid over loaded by the high voltage?. I would get the alternator fixed then see if it cures the cutting out

It doesn't have a stop solenoid, you just push the throttle lever right forward.

 

[Abacus]

I think it has an electric lift pump you should be able to hear it when the key is on

 

[rob h]

It doesn't have a stop solenoid, you just push the throttle lever right forward.

Well that makes it simpler. Just check all fuel lines and filters and blow out any lines filter heads you can

 

[Wisconsonian]

Check the voltage on all the connections on the alternator, with the key off, then with the key on, then running. Really need to know the alternator brand to find a wiring diagram to follow.

Japanese engines like to hide a screen inside a banjo bolt on the intake to the fuel pump. That's the first thing to rule out. Even if you don't have a screen inside a banjo bolt, take the fuel suction pipes apart and blow the crud out, see if the fuel flow improves.

 

[jellybean]

Here some pics, as you can see I have the latest Aircon version, the cab was so rusty that I cut it all off some years ago. Actually much nicer to work without the cab. Yo can see it has honked out right in my farm track so a bit of a nuisance but I can get around by going through fields. I might have to try towing it to the workshop with the tractor, would that work if I wedge the track motor levers in forward. Trouble is being on my own steering might be a problem.
The electric fuel pump that is on there is new but I have just cleaned and tested the old one and I think it is delivering more diesel than the new one. Still waiting for battery to charge up before doing more.

The alternator is an HC-Cargo110258 14v 35 Amp. Obviously I need to fix the over high charging but without being able to run the engine I cannot check the output. There are no electrics on the digger except those needed to run the engine, everything else came off with the cab. So as far as I know its only the electric fuel pump and various gauges on the dash. I will probably find the fuel problem eventually but have no idea how to fix the alternator/regulator apart from taking it off and taking to Alterstart in Barnstaple.

 

[TripleSix]

Here some pics, as you can see I have the latest Aircon version, the cab was so rusty that I cut it all off some years ago. Actually much nicer to work without the cab. Yo can see it has honked out right in my farm track so a bit of a nuisance but I can get around by going through fields. I might have to try towing it to the workshop with the tractor, would that work if I wedge the track motor levers in forward. Trouble is being on my own steering might be a problem.
The electric fuel pump that is on there is new but I have just cleaned and tested the old one and I think it is delivering more diesel than the new one. Still waiting for battery to charge up before doing more.

The alternator is an HC-Cargo110258 14v 35 Amp. Obviously I need to fix the over high charging but without being able to run the engine I cannot check the output. There are no electrics on the digger except those needed to run the engine, everything else came off with the cab. So as far as I know its only the electric fuel pump and various gauges on the dash. I will probably find the fuel problem eventually but have no idea how to fix the alternator/regulator apart from taking it off and taking to Alterstart in Barnstaple.


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Is the clicky clacky pump pumping well?

Is the pump pulling or pushing through the fuel filter?

That clear braided hose wants changing, it goes hard and let's air in at the connections

 

[jellybean]

Diesel comes from the tank into the cartridge filter and then through the braided hose to the electric fuel pump. If the tank is fairly full it will just gravity feed all the way to the electric pump. I will change the braided lines. Sucking in air could be the problem. The injector pump is a sod to bleed. the digger did nearly 2 days good work before stopping so I find it hard to believe the injector pump is at fault.
I still haven't managed to locate any voltage regulator though and need to solve that before I fry anymore batteries.

Many thanks for the help so far, it's great to have some support.

 

[TripleSix]

Diesel comes from the tank into the cartridge filter and then through the braided hose to the electric fuel pump. If the tank is fairly full it will just gravity feed all the way to the electric pump. I will change the braided lines. Sucking in air could be the problem. The injector pump is a sod to bleed. the digger did nearly 2 days good work before stopping so I find it hard to believe the injector pump is at fault.
I still haven't managed to locate any voltage regulator though and need to solve that before I fry anymore batteries.

Many thanks for the help so far, it's great to have some support.

I'd push the fuel through the filter with the pump.

Might be wise to install a mesh filter between tank and electric pump.

Kubota alternators are usually internally regulated.

 

[box]

The alternator is an HC-Cargo110258 14v 35 Amp.

Google tells me it's externally regulated. You must have a regulator hidden somewhere on the digger.

 

[jellybean]

I managed to drag the digger to a more accessible place with the tractor, only about 60 yards. Have also found the voltage regulator under the instrument panel, Nippon Denso 026000-2121 and ordered a new one. Next job replace the fuel lines and try to bleed it through. Fingers crossed!

 

[flywheel]

Do you get any diesel coming to injector s.?

 

[jellybean]

Do you get any diesel coming to injector s.?

Not got that far yet, will wait till I get the regulator done. I know it takes ages to get fuel through the pump and injectors and I need extra hands to crank while I bleed. But I am making progress.