Miller Pipe Pro - Kubota D1005 - Central Georgia Generator Rework Project

[pdeal]

I have a new project going here.

About 2 years ago I bought a Miller Pipe Pro 304 welder. I didn't know a lot about it other than it had a Kubota engine in it. It had 2500 hours, engine ran well, and the generator worked. It turned out to be an engine driven inverter welder. Not well executed at all on Miller's part. I have several Miller welders and generally like their stuff but this is a piece of garbage on many fronts. I got the welder working and it quit soon after. The generator was a 2 pole generator so would run at 3600 rpm. Additionally, the generator voltage regulator on it is somewhat intertwined with the welder so it's hard to separate the two. The engine is the only bright side of the thing. It's a Kubota D1005.

The engine didn't come with an SAE bell housing or flywheel. It had  a Miller home made adapter. I debated about how to go and decided first to just buy a flywheel and bell housing on ebay. That turned out to be a rat hole. I wound up with an SAE 5 bell housing and an SAE 6.5 flywheel. This is what I needed but the bell housing is a short one and the flywheel a long one and the two won't work together. I was able to return the flywheel. Still stuck with the bell housing for now.

I wound up ordering a bell housing/flywheel kit from Central Georgia Generator along with one of their 11kw single bearing generators. It's all here. The bell housing/flywheel kit is not on their web site so I didn't know that was an option at first. I'm having to do some carving on the welder chassis to get it all to fit. I have some bolts and vibration isolators on order from McMaster Carr and then will proceed.

One issue I hope won't be insurmountable is that the engine is two speed. It's set to 'idle' at 2400 or so and kick up to 3600 when the generator gets loaded. There is a second solenoid in there to do the speed change. I can remove this. I think the engine defaults to the lower speed. I can turn the speed down to 1800 but I'm hoping that the governor will still regulate well there. Not much on the internet on the governors on these engines.

Pictures below-

I made this skid for it soon after receiving it. Also tried to close up all the holes where varmints could get in. I've since painted it and put new decals on it. I think I will rip the Miller decals off though since it's not much miller anymore.
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New bell housing and fly wheel...
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[pdeal]

Another picture with the generator sitting in there. I need to build a support for the generator end.
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[Henry W]

I've built a generator with a D1005 years ago. Here it is:

https://microcogen.info/index.php?topic=1743.0

The flywheel and housing you have is the 3600 rpm rated setup.

I put the same setup on my build. Than I found out that the D1005 BG series that are spec'd for 1800 rpm generators have a larger diameter and heavier and thinner flywheel. The housing is shallower also. I wrote and posted pictures about this. At the time I was able to buy the 1800 rpm setup at a good price. Check post #65 through #67 in the link I posted above.

This is going to be interesting to see how the engine will perform at 1800. If your able to take pictures of the injector pump showing the  throttle lever, limit screws and shut off lever I might be able to help.

Caution
Do not start up the engine with the generator head mounted until you know for sure that the engine will start up and run below 1800 on initial startup. 1800 rpm generator heads have been known to blow apart when rpm's are exceeding the rated speed.

Tom is a great guy! Known him for years. Your in good hands. If you need advice or run into any problems he will help you.

Henry

[pdeal]

Here is a photo of my governor side plate. Looks like the one on your engine Henry.

Thanks for the heads up on the startup speed. Will do.

My bell housing looks just like yours. Hard to see mine in the photo but it's the same. Tom Osborn at CGG said it was the one I need. I also have a light plant with a D905 and it has the SAE 5 bell housing too but it's thinner like the other one I bought. Tom said the thinner ones also had the thinner lighter flywheel and were for applications where good regulation is not needed.

I've done some experimenting with my light plant generator. It has a Marathon Pancake generator head. These are really not good generators for general use. They don't start motor loads well at all.

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[Henry W]

It looks like the engine has a fuel shut off selonoid.

Looking at the pictures, the throttle lever is in a different position then what I had. is the governor in the low speed position?


About the flywheels and housings, there are many configurations. When I purchased the 2nd housing and flywheel that was for 1800 rpm. generators.(the D1005 BG series) It was thinner, larger in diameter and heavier than the one I originally purchased and that you posted in your pictures.

I edited my first post. It gives location where pictures can be seen.

[pdeal]

Ok, disconnected the high/low solenoid, got it adjusted down to about 1830 rpm. Also set the top end limit screw down so it can't be rev'd up much at all. Will tweak later.

[Henry W]

You got it. 1830 is fine. Leave it there and see how the genset responds on a load.

[Henry W]

The Kubota D1005 engine I purchased was spec'd for a Bobcat skid loader. The governor worked very well. I believe the frequency drop from no load to full load was about 2 Hertz. Once I've stressed the generator out under full load I realized that the governor regulation was good enough as is was and I was never concerned about it.

It's best to first set the engine speed with no load to 62Hz. Than set the voltage on the AVR. Tom at CGG knows what's best. Than start loading the genset up and watch the frequency drop and voltage regulation at the same time. Once you reach full load and frequency stays at 58Hz or above you should be fine.

I would think the frequency when fully loaded will be around 59Hz or above. My experience is, Kubota governor's regulate rpm's very well.

I'm looking forward seeing the test results.

Great project! And I like the enclosure.

Henry

[pdeal]

Thanks!

What do you use for a test load. I have some 1kw approx space heaters that I was thinking of using but that won't get me too close to 10kw. I have some big power resistors. Need to see what can be done with those. I stupidly threw some 3-4 kw heaters out.

The advantage to this setup is that much of the little stuff that winds up adding a lot to the price is there. Fuel tank, water separator, outlets, circuit breakers, etc.

It is taking some carving with the plasma cutter to make it fit and some refabricating but that's ok. I'm pretty well setup for that stuff.

Henry- I read your story on building the generator from the Z482(?) engine. It's good I read that. There is a guy near here that has one for $600. Not bad but I don't want a 3600 rpm generator. What I really like about a diesel is it running at 1800.

[Henry W]

I used different combinations. The electric appliances are of follows. 240 volt oven/stove, electric water heater, 2-1/2 ton heat pump with emergency back up heat, well pump and lights.

The Direct drive Kubota powered Z482 genset was a nice little unit. If I would ever do another one it would be belt driven at 2800 rpm. It would handle 5000 watts.

Is that $600 for a complete genset, or just the engine. If its complete, and it runs fine. You should buy it and convert it as I mentioned above.
I would even consider buying it.
Henry

[pdeal]

No the $600 for just the engine. Decent looking engine though. The guy was not 100% sure of the hours. It came from a small generator.

[Henry W]

That is still a good price if it's in good shape.

[pdeal]

Well it's in southwestern pa. In the Morgantown, wv Craigslist. I don't have the time or money for it now.

[Henry W]

Ive been doing some thinking and more reading. It seems that the mass on the flywheel you have will work just fine for 1800 rpm generators. Some generator builders use the flywheel and housing setup that you have and some use the thinner flywheel and housing combo. The reason for the thinner setup is to reduce the size of generators. Different OEM manufacturers have their own spec'd parts. Onan is notorious for this.

In the marine industry, space is precious. If you ever been in an engine compartment in a small yacht you would understand why it is so important to shave off as much length where its possible.


One thing I do like about the housing you have is that its stronger. More mounting surface which requires more fasteners. It has a pad on top of the housing to mount air cleaner or other things. Its beefier.

The flywheel also has advantages. It has provisions to be used for single or dual bearing generator heads. And that is a good feature to have.

Henry

[pdeal]

Update:

I have a bunch of stuff going on here so progress isn't as fast as I'd like. I had to plasma cut a few more things out of the way of the generator. I received the bolts and vibration isolators. The engine only sits on two vibration isolators so I had to shim it up till the bell housing was plumb relative to everything else. Then I set the generator in and figured out how high the base that it would sit on needed to be. I got the base all cut out of some scrap channel I had and set uit in, set the generator back in with the vibration isolators in place and did a trial bolt up. I got the base and isolators sitting in place and where they need to go marked out. Looks pretty good.

Next step is to pull the generator back out, clean the whole welder housing out and weld the generator base in place. Do a little painting and put the generator in place permanently.

Another thing I am totally unimpressed with Miller's implementation of this welder is how weather and rodent proof it isn't. Why the heck they would leave the housing full of big holes that mice can get in and the top so it doesn't shed water is beyond me and very poor quality. I hope to address some of these issues.

I have a 25kw Wacker tow behind generator that we use as a backup generator here normally. This thing is very nicely implemented. Very weatherproof.

Henry, I don't know much about what goes into selecting the flywheels for these things. I do figure I'll be ok as you said. It came from CGG knowing the application. Also, the new flywheel is heavier than the old one that was on the welder which was designed for 3600rpm.