Onan generator- off topic!

I think I changed the pump when I changed the engine in 2008, but it was dead if winter (the 24 Feb) and I was broke, so maybe I didn't.

The truck had about 365-75 at that point

Good grief. How many does it have now?

470 something....

Carb came in! I would try to put it on tomorrow, but I have 2 fig trees to plant and I'll be pressed for time. So hopefully monday.

I have two generators, the ~$2,000 Onan that came in my motorhome and the ~$400 PowerHorse I bought when a storm took out our power for close to a week.  Both are 4KW and that's about where the resemblance ends.

The Onan has electric start, which is nice for being able to start it from inside the motorhome on a road trip in the morning to get the microwave working to heat up breakfast.  But honestly, I'd trade that for the ability to pull-start it when both batteries are dead.

Other than that (dubious) advantage to the Onan, the PowerHorse is by far the better product.  The Onan cranks forever to start, especially when it's cold.  The PowerHorse starts on the first pull, every time, no matter how long it's been sitting.  To be fair, I've never tried starting the PowerHorse in temps below about 50°, but even at 70° the Onan will crank forever.

I was told I needed to run the Onan under load for a while every month to keep the carb clean.  I've never had to do that with any other engine, so I didn't.  Then after one of the first winters I owned it I couldn't get it to run well.  The carb couldn't be disassembled to be cleaned, so it needed a new carb.  I didn't want to try to fight with it under the motorhome so I took it in and $1000 later it has a new carb and I run it every month religiously.  In contrast the PowerHorse has sat for a year or two and still started on the first pull and ran smoothly when I finally needed it.  I think the gas in it now is at least 4 year old E10, and I'm sure it will start right up if I need it too.  (I do put Sea Foam in the gas in it)

This next comparison maybe isn't fair, because the Onan does have more hours on it.  But one of the times I was trying to run it just to run it it kept shutting off with a blinking light.  Turns out it was an error code that the voltage regulator wasn't working correctly.  $1000 later it was running again.  The PowerHorse just keeps working.

I have some Onan experience...posted on her a couple years ago.

https://forum.garysgaragemahal.com/Any-Ford-RV-Motorhome-experts-on-here-tp23069p63915.html

I bought a 31ft 1993 E350 Motorhome with a non-working Onan underslung generator. There turned out to be several problems with it that I figured out one at a time. After that, the thing purred like a kitten and worked like a champ! The main issue with the thing was that the RV had had some winter miles on it, and the road salt and grime had gotten to the main circuit board in the generator and fried it. I found a new upgraded circuit board online, and she fired right up. I did a full tune up and replaced the main bearing in the end housing and she was golden.

One interesting thing to note...and it took me a while to figure this out...but I had terrible problems with the thing randomly not starting. It would turn over just fine, but would not fire up. If we were driving the RV down the road and pulled over for a bit it would start right up, no problem. If it had been sitting for a bit, it absolutely would not start.

I later figured out that the new circuit board needed a specific minimum voltage in order for the ignition to work. I don't know what that exact number was, but I assumed it was around 12.5v, or even higher. So the big battery in the motorhome, even at 12.5v would spin the Onan starter over like a whirlwind, but it would not allow spark. If the voltage was above about 13v, it started every single time.

I have seen the exact same situation with some older Kawasaki motorcycles...specifically a couple different ZRX1200R's. They were carbed, but had electronic ignition modules. If the battery had 11.9v, the starter would crank the engine over all day, but the ignition modules needed (I think) 12v or higher to provide spark. It was weird, because with a boost they'd start no problem, same as that Onan generator.

Anyway, just a rambling story with my morning coffee. Good luck with the Onan! They're fun to work on.

That's strange. From everything I've heard, Onan is as good as it gets.

That's something I'll definitely keep an eye on.

Got the fig trees planted. Hopefully I'll have enough time to put the carb on.

Rembrant wrote

....  The main issue with the thing was that the RV had had some winter miles on it, and the road salt and grime had gotten to the main circuit board in the generator and fried it....

Good point.  I don't know that mine had that hard a life.but it is definitely in a harsher environment than my PowerHorse.

Nothing Special wrote

Rembrant wrote

....  The main issue with the thing was that the RV had had some winter miles on it, and the road salt and grime had gotten to the main circuit board in the generator and fried it....

Good point.  I don't know that mine had that hard a life.but it is definitely in a harsher environment than my PowerHorse.

Ya, unfortunately for me my RV had had some winter miles on her. The underslung generator position I'm sure is perfectly fine in better climates. The replacement circuit board I bought had some upgrades over the original, one of which was a complete gel coat or similar clear coating that protected it.

Carb is on, but now I need a starter solenoid, and some weather stripping. Will try to get pics soon.

What kind of starter?

Have you looked at Texas Industrial Electric?

They have a VAST assortment of quality components.
Gary was impressed with their service and knowledge.

Just a regular Ford style. Part# 2SS3 in my system. I've got it most of the way back together now. Next step is wiring.

Okay, I didn't realize that it was something common.  

TIE is excellent, and Maniac Electric Motors is a great source for starter & alternator needs.  💡

Snowbirds for a reason....

deep!

No idea how "deep!" ended up in there. I didn't type that.

My phone puts words in my mouth all the time!  

Generator is running! Wired it up(minus the actual "generator" part), put some gas in the carb, fiddled with the choke, and it fires right up. Runs good. Now I just have to make it work.