Onan Microlite 2800 generator woes

[RV-there-yet]

2000 Pleasure Way Excel RD (Dodge). I've had the van for a year. The genset was not working when I bought it. Previous owner hadn't used it for the previous year so that's at least 2 years non-functioning. I'm making progress but I need to know for sure what I have so I read the troubleshooting guides correctly. I dropped the genset out of the bottom of the van to work on. There is a 1994 date sticker on the underside of the cover so I know it's not original to the van. All the trouble shooting guides talk about model names with 2 or 3 letters (KY, KW, BGE, NHE, etc) and specs A, B, C, etc up to K.

How do I know what I have? The model number on the valve cover is 2.8KVFA26100C. Does that make it a KV, Spec C?

Started out not cranking at all. Then it cranked but wouldn't start. Dropped the genset out of the van and got it to start but won't run after I let off the start button.

Thanks for any help.

[Rocinante]

If it were me, as I am nowhere near as handy as you clearly are, I would take it straight to a Cummins dealer / service center near me. Cummins acquired Onan, so I'm thinking they would be able to figure out what model it is, what's going on, and most likely even get it running smoothly again. Best wishes for a successful effort!

[mkguitar]

others often suggest a small motor repair shop as more experienced "outside the box" and less expensive genny service


can;t think what would allow start but stop when starter released- I'd be interested in knowing -sounds like wiring fault
mike

[booster]

Originally Posted by mkguitar

others often suggest a small motor repair shop as more experienced "outside the box" and less expensive genny service


can;t think what would allow start but stop when starter released- I'd be interested in knowing -sounds like wiring fault
mike

I have heard in the past that the start switch bypasses the normal ignition system and when released it will quit if the primary ignition is bad. I don't know it for a fact, but his been mentioned several times in the past. Very similar to losing the ballast resistor on an old vehicle with points ignition as that is what they would do.

[mkguitar]

Originally Posted by booster

I have heard in the past that the start switch bypasses the normal ignition system and when released it will quit if the primary ignition is bad. I don't know it for a fact, but his been mentioned several times in the past. Very similar to loosing the ballast resistor on an old vehicle with points ignition as that is what they would do.

Just looking at the manual, there is a shutdown relay- could be bad or a wiring issue if it is not staying energized when the start switch is released

[RV-there-yet]

Now it seems to not be pumping fuel. All the part numbers I pull off this thing seem to be obsolete. Found a troubleshooting guide at flightsystems.com and they mention that both issues could be related to the control board. That would be nice if replacing one part made the whole thing better.

[mkguitar]

do you have the manual?


i found it online and downloaded


https://www.google.com/url?sa=t&rct=...kRIYYiU9d9WdHz



Mike

[SteveJ]

A bad voltage regulator board can/will cause the genny to shut down when you let go of the starter. A lot of times the increase in resistance at the slip rings(mainly due to lack of use and monthly exercise) will take out the regulator. A bad low oil sensor will also cause a shut down. The manual will list the proper resistance and voltage values and techniques for troubleshooting. Taking the genny to Cummins would run well north of a grand, I think.

[RV-there-yet]

When I first started this odyssey, I changed the fuel filter to a clear plastic one so I could see if fuel was flowing. I confirmed fuel flow when cranking but it wouldn't fire. Fast forward to today (now that the genny is on the ground). No more fuel flow. Pulled the fuel pump and tested it by putting power to one side and grounding the other. Had the inlet attached to a fuel hose dunked in a gas jug. The outlet had a short hose attached that dumped into an empty gas jug. The pump made sounds like it was running but no fuel was pumped.

Went to Rocky Mountain Cummins here in Salt Lake and bought a new fuel pump ($65), new air filter ($13) and a new sparkplug ($5). Shout out to Ralph Gilger at the parts counter. He was patient, looked through his system as well as his old books that he never throws away and got me the help I needed.

Installed the new fuel pump and it started and died after a couple of minutes. This is progress. It hasn't ever run that long before. I kept starting it each time it died. 10 sec, 3 sec, 2 min, 3 min. Put some Gumout in the 2 gas gas jug I'm pulling fuel from and kept trying. Same result, ran for anywhere from a few seconds to a few minutes. Then it started and never died. Ran for 28 minutes without a hiccup until my wife decided we should go for our daily walk. I shut it down rather than leave it unattended. When we got back I fired it up again and it's now been running 25 minutes. I'll let it go an hour then if it doesn't die I think it's time to reinstall it in the van so I can put a load on it.

I suppose a weak fuel pump was the main culprit but I don't doubt the carb needs that Gumout treatment as well.

[Bobd254]

I would suggest trying to get a good load on it before you reinstall it. Mine hadnt been used for probably many years. I got it about 18 months ago. A 2000 van with 25 hrs on the genset. When the repairman got it stsrted it wouldnt take a load at first. He had .to do something else, im not sure what.
Not much help, but id try to put a load on it first.
Bob

[themexicandoctor]

My 2 Cents is find a competent* Lawn Mower** Shop that can help you.

And or find a Generator Specialist (usually more expensive)


*the tricky part
**that also work on Generators

You are 1/3rd or more already there. And about 50% of the heavy lifting jas been done, lowering the unit.

I had 2 instances with a 2.8 Onan that needed repair; the unit wouldn't idle but it was getting gas - turned out to be a $9 nylon part that had worn a groove in the nylon which on my iteration of 04/05 Onan that usually fails over time.

The cost of dropping, repairing, testing (I asked for a complete overhaul), adding a junction box & then reinstalling was $800 by Larry at Oliphant in Los Angeles (Generator Guru).

Then more than a year later, at a critical time, whenever I ran the Generator ny Magnum MMS1012 woukd light up with the warning HIGH AC. This warning means Regulator Failure.

Larry was on Covid Break at the time & my RV Guy said for him to do it, the Regulator would be $250-300 - plus another $500-550 to drop ot, work on it, put it back in simply because he doesn't like working on Generators unless he has to because of the labour involved when he was snowed under. He said

"Here, let's cannabilize this regulator off a junked Generator & if it works call, pay me $50 afterwards but call this guy Ivon wo has a lawnmower shop & who we used to farm out our generator work to ..."

Bottom line; $231 total for the work, plus a $30 tip & $50 for the regulator part .

Why am I going to the trouble of sharing this; its because I don't know generators but there are some very competent people who don't work in the RV Biz directly who can help you & save you some money. Plus if it is the regulator, you might be able to scavenge one locally & havr it tested on a bench before reinstalling it.

I hope this helps.

Plus when it comes to long distance trouble shooting by Booster & others, they usually hit the nail on the head.

[themexicandoctor]

Just in case we are blessed by the same iteration, my unit has these figures which I scribbled on the Owners Manual, Day One;

2.8 KVFA26100K

D050774813

[RV-there-yet]

Mine is 2.8KVFA26100C. Put a load on it tonight, a heat gun boasting 1200W plus a space heater with 1500W on the label. The genset lugged down but it held on. I'm calling it good and I'm calling myself lucky. Thanks for the suggestions for the future.

As far as dropping the unit out of the coach, having now done it once, I'm not afraid to do it again. I used a rolling floor jack and it went well. A couple of oopses that I can now avoid in the future plus I learned a lot. I'll let you know if I feel the same way after I hoist it back into position tomorrow.

[mkguitar]

that's a good load- about 22.5 amps

I'd appreciate ( for the day I do mine) that you take some pics of the process and connections made as you remount the genny


I have a dual parallelogram motorcycle lift which is dandy for that ( or transmissions)


btw some of us with gunked up carbs found that continued use got better and better and it seemed that the agitation of driving the van helped further to clean up the carb




cheers, Mike

[themexicandoctor]

Hallelujah as they say in Mali.

I do not know what a junction Box is however after my guy did the overhaul he added one - I guess Roadtrek thought they would never need to come out.

CAN ANYONE TELL ME WHAT THE JUNCTION BOX IS PLEASE - I saw the new hardware in there.

Thank you for the correction, by the time I started typing I overlooked the C which was clearly presented at the beginning.

For a lot of people, getting it in & out is the toughest part but you know what you are doing

[Peder_y2k]

Keep using a fuel system cleaner in gas tank, like Seafoam, Marvel Mystery Oil, Spectron, Techron, Sta-Bil, etc. as their chemistry will minimize carb clogging deposits. Then run the genny once a month. On systems with dedicated fuel tank, run genny every 5 years (exageration).
Another helpful method is install a fuel valve to cut off fuel supply to run the genny making the carb dry. No fuel, no deposits.
I have an Onan 4.0 with fuel cut off valve, resulting in perfect starts and running every time with infrequent useage.
Its the stagnant fuel that is the true issue.

[capseaweed]

If your gas Onan Microlite 2800 generator has not been run in 1 or more years but will turn over but not start, I would start with the carb. put it and clean it. If you don"t want to do that just buy one off of Ebay they are in the 30 to 50 dollar range. make sure you have more than 1/3 gas in your gas tank. Check the oil level, maker sure it is at 1/2 or more but not over or under filled. Change out the fuel filter and pump if you have them. They like, the carb, get clogged from sitting and not being run. The final thing after you have done all this and the gen set still doesn't run is see if you have a separate voltage regulator and change it out they are about 30 or so dollars. All in all for about 2 hundred dollars you will be able to get your unit running.
All this can be done with the unit in the coach.
good luck
thom
207 RT RS

[gimpy666]

I have an Onan 2500 the propane model and failure to start is most often a bad ground. It is on any generator the same boats as well as RV's.

[Joe]

I have no idea how much money and time I have put into my Onan 2800. New carburetor, spark plug, 2 air filters, low oil senser, 2 fuel pumps (heat in casing kills them) starter, muffler, tail pipe and fly wheel. Probibly other parts I forgot. Onan dealer twice but never truly ran great. Found small engine repair shop in Maryland. Knock on wood all us great! Not a big fan of Onan but its what I have and only thing that fits in compartment. Have taken out so many times. I can remove in short time.