American Coach: Generator's Mid to Early 1990's

[NHRA225]

I'm not much of a Blogger, but I've been asked to share my experiences with the Mid to early 90's Generators and options. So here it go's.
If You own a mid 90's to early 90's and prior Diesel Pusher - Chances are you have an Onan DKDFJ series Generator. This Genny came in 2 sizes the 8.0 KW and the 7.5 KW. They were originally designed for Boats- Mainly Sail Boats but may be found under the decks of all kinds of watercraft in the 1970's and 1980's. The RV Industry picked the DKD's -I'm guessing from Onan- makes sense to me.
We'll take a little about the Newer QD series later.
My 92 Eagle is my Horse- It's solely used to haul my 10,000 Race Trailer to Drag Race events mainly East of the Mississippi, I used to rack up about 20,00 miles a year. During the events My Generator will run nonstop for Weeks literally at time, especially in Hot weather.
I had an issue with overheating many Moons ago when a a failed Temp SW decided not to work any longer which in turn failed to turn on the Radiator fan- Either way I pulled the engine and installed a rebuilt from a reputable shop in Ohio., It ran fine after that.
Fast forward.
The past few Outings I noticed that the Governor was no long operating when it received a load as it would drop in rpm which in tern drops voltage and Just as important Hertz.
Example: It would drop from 115 Volt/60 Hertz to 109volts and 53 Hertz, I thought Humm ?
2 weeks ago I performed a Leak Test on the Cylinders and got a Shock. A leak test is similar to a Compression test only it provides a % of leakage- more important to know verses compression numbers.
Cylinder #1 leaked @ 20 %--#2-- 23%--#3-- 21%- Now- A typical efficient Engine will leak at 2 to 5% if the rings are in good shape.
SO ! With that said the Little Kubota D50 is Toast ! Time to implement a plan of Action., What is it you ask ?
Here Ya go !
I have collected 2 Onan Spare Generators over the Years, One was a Donation from a Good Friend on here, and it had way too many hands on it when He dropped it off along with a box of Bolts, Parts and Pieces, maybe He'l chime in here. It's a HDKAJ 7.5 KW and is back together and Ready for Duty.
The other is a DKDFJ 7.5 KW that I purchased for whatever reason 5 years ago, Maybe I was planning for a power back up for the house- think that's what I told the Wife anyhow. It has 247 Hours of Exercise time only and it looks Brand New. Bought from a Fire Station in upper Michigan, it's out of a Crashed Fire truck and sat in a heated warehouse for 8 years .
Those are my 2 install options as of Yesterday-
I have install size issues with both, The HDKAJ will fit with a re fabricated Cradle, But will be difficult to service, IE: removing the panels - the slide out isn't wide nor long enough for the mounting footprint-
You can see the original DKD fits like it was Engineered to do so.
The New DKD is a different Spec # --It is a stand alone self contained unit that all it need is a Fuel source and a Battery and you could run in a field.
My Older DKD- Different Spec # is not self contained as the controls are or were mounted up and inside the MH attached with cables and plugs.
So I will re fabricate the Cradle lowering it 3 inches to achieve clearance for the self contained control box mounted on the Generator.
See the Generator pictures below-- the Newer is on the left and the older on the Right.
Break Time- Back tomorrow !

[GlennLever]

By too many hands on he means two different service centers tried on three different occasions to fix oil leaks.

Caledonia RV pulled the unit out twice (at my expense) and it still leaked afterward. It then went to Buffalo Cummins/Onan who told me it was broke and needed lots of work $'s

Under stand this had been a running operation generator that had been to Bowling Green (Beach Bend Race Track) in 100+ degrees and 100% humidity. It ran constantly running to A/C units and any thing else I asked of it. They charged me 6 hours of labor to remove it from the motor home.

I told them to stop and picked up boxes of parts (this was in there parking lot).




and purchased a used generator and installed it in an morning.

Generator install

[NHRA225]

Glenn-
That was fiasco for sure !

Update:
Yesterday was a full workday for sure.
MH went to my Fabricator - Friend -for Cutting and dropping the Cradle 3 inches in order to provide adequate clearance for the New DKDFJ and for possibly installing the HDKAJ in the future.
Had to transfer numerous parts to the New DKD and I installed a New Spark Arrester I picked up from Cummins.
Picking up the MH this afternoon and will begin the re-install - My list is still lengthy which includes cleaning and painting the Cradle and Side rails
Picking up all new Bolts and Nylocs -- muffler hangers -ECT.

Below is a shot of the modified Cradle and the New Dkd Ready for install.

[GlennLever]

Originally Posted by NHRA225

Glenn-
That was fiasco for sure !

Update:
Yesterday was a full workday for sure.
MH went to my Fabricator - Friend -for Cutting and dropping the Cradle 3 inches in order to provide adequate clearance for the New DKDFJ and for possibly installing the HDKAJ in the future.
Had to transfer numerous parts to the New DKD and I installed a New Spark Arrester I picked up from Cummins.
Picking up the MH this afternoon and will begin the re-install - My list is still lengthy which includes cleaning and painting the Cradle and Side rails
Picking up all new Bolts and Nylocs -- muffler hangers -ECT.

Below is a shot of the modified Cradle and the New Dkd Ready for install.

You do good work, are you for hire?

[NHRA225]

You do good work, are you for hire?
You couldn't afford me ! LOL !
MH back home and Painted the Cradle this afternoon - 2 coats of Rust-oleum Black of course.
Next ? Slide this Baby back in - It has 3 mounting points and should be easier than pulling it with an extra 3 in of clearance.. Hot and Humid here - makes for a slower pace- Plus I have Lawn Mowing and Pool Patrol the rest of the day. I'll get up at 5:30 (my usual time) and at the first crack of light I'll proceed with the button up of this project.

[GlennLever]

Originally Posted by NHRA225

You do good work, are you for hire?
You couldn't afford me ! LOL !
MH back home and Painted the Cradle this afternoon - 2 coats of Rust-oleum Black of course.
Next ? Slide this Baby back in - It has 3 mounting points and should be easier than pulling it with an extra 3 in of clearance.. Hot and Humid here - makes for a slower pace- Plus I have Lawn Mowing and Pool Patrol the rest of the day. I'll get up at 5:30 (my usual time) and at the first crack of light I'll proceed with the button up of this project.

You would have the same problem with me, you could not afford me.


Looking really nice.

[mackwrench]

Im willing to help!
I'm not sure if I'm cheap or expensive. Right now I only work for food, housing, electricity, a little beer, a lot of diet Coke.....and my wife.(maybe that's the $$$ part)

Any rate, good job. My gen-set only has 2k hours, so hopefully I'll not ever see it on the shop floor.

[NHRA225]

Originally Posted by mackwrench

Im willing to help!
I'm not sure if I'm cheap or expensive. Right now I only work for food, housing, electricity, a little beer, a lot of diet Coke.....and my wife.(maybe that's the $$$ part)
Any rate, good job. My gen-set only has 2k hours, so hopefully I'll not ever see it on the shop floor.

Your Welcome anytime !
Genny Project is all done - Load tested with both a/c's on and micro wave -- 94 deg Heat -- 115 Volts @ 60.2 Hertz- doesn't even Fluctuate with varying Loads- I'm a happy camper ! For now.
Next -- New Residential Refrigerator in place of my Very old Dometic 3 way . Story for another day !

[Truckerdave]

I have got to ask, How many hours are these generators good for? I think mine has about 3600 hours on it.

[NHRA225]

The DKD I removed had just over 37,000 hours- The Generator section works fine, The engine is just tired.
My New one has 275 hours. Just Change the Oil and Filters including looking at or changing the Air Filter too. Every 200 hours.