Hobart Champion 16 Welder/generator..Onan Performer 16 engine

[docrocky]

This unit is about 15 yrs old with only 110 hours running time. It was used mostly as a back up generator and occasional stick welding of heavy farm implements. I tried to start it up this summer because of a threatened storm, but could not get to run. I had started it up and test run about 3 months before at which I had to change the fuel filter and hose and it was ok then.

Now it turns over ok and if I give it fuel directly to the carb it will run then die as soon as fuel is consumed. So I am assuming it has spark and compression ok.

I took the Kiii (?) fuel pump apart but all looked ok and I reassembled with light gasket to all gasket surfaces. I also blew out all the hoses and into the carb. I put it all back together again and tried to start it up but it only fires if i feed fuel to the carb. I assumed that the pump was not working but when I disconnected the "out" hose to the carb and turned the engine over there was good fuel pressure/pulsate flow. Question at this point is: Does the idler governor have control at this point, or is my problem with the carb, which I have not taken apart as yet.

Anyone have experience with this engine (Onan 16) and am I on the right track. I hesitate to haul it to the shop if it is relatively simple to correct. It it was an issue with the welder or the generate, I wouldn't hesitate to get it to qualified people, but if it strictly engine then I am assuming I should be able to correct it.

Also note in the pictures the rust cover on the condenser, but I am assuming it is functioning properly since I have ample spark with the firing. Also i am inserting the picture of the fuel pump as well as the idler controller, which I assume works only when welding or drawing generator power.

Thank You

 

[CNC Dan]

Could be a stuck needle valve. Try removing the carb. bowl and see if the float is free. If it's all gunked up, use some carb. cleaner on it. Should free up OK. Sometimes you can spray carb. cleaner into the openings in the throat of the carb. and free things up, but I would pull the bowl.

 

[deereman75]

I would say carb. 99% of small engine issues I see are carb...

First, (as recomended) pull the bowl and make sure everything is moving right.
The bowl will likely be full of goop, and will need cleaning. It should have a little needle attached to the bowl, pull it out and spray carb cleaner through the passage it goes in. Pull off the fuel line, and spray cleaner through the inlet. If the carb has a removable plug for the jet, take it out, and poke a thin wire through, it will often be full of crud. Spray with carb cleaner. Basically take off everything you can, clean as well as possible, and put back where it came from. I recomend only removing one piece at a time, and putting it back before the next one if possible. The first few carbs you do, its really easy to get some little thing wrong, and that can be a huge pain to find and fix.


Let me know if you need any more help, I have worked on way too many small engine carbs..... LOL

 

[docrocky]

Thanks for the reply s, both of you. I pretty much did what you recommended today. There was a small amount of gunk at the bottom of the bowl but best i could tell the black plastic floats were not stuck. The needle valve was free in moving and the ?rubber tip was clean. I did meticulously spray and clean with carb cleaner then air compressor blew thru all the ports and tubes. In taking apart the top portion of the carb (Nikki 6100 27-261) a small flap in the gasket developed but the 98% remained attached to the lower portion of the carb body, I re approximated the small flap and used gasket sealer to secure it in place. It did not involve any edges. I thought I would let it reseal overnight before giving it a test startup.

 

[docrocky]

deereman75 & CNC Dan: I did what you both suggested and i finally got it to start and run, but she sputtered for almost 10 minutes, then stopped.I completely drained the ffuel tank and gave it 1 day old purchased gas. I also kept cleaning the spark plugs (brand new 1 day ago) which were carbon covered but no gunk. I even cleaned out the cylinders because I had given it a light oil spray and could see a faint haze as I turned over the engine with the plugs removed.I finally got it to run at its full throttle, but after about 10+ minutes of continuous run she started to sputter again and eventually died again. At a later run, I had the airfilter off looking directly to carb inlet and I notes as it ran there was a definite throw back of fuel thru the air intake portal. Is this all carb malfunction?

The fuel line from the fuel pump to the carb is old and stiff. Where it attaches to the pump there is a small crack but i see no fuel leakage here. Could a small air leak here cause the difficulity?

The condenser is heavily rust covered, so could this be causing a a weaker or intermittent spark?

Any thoughts???

 

[Fifelaker]

As soon as it dies check for spark. That said I would change that condenser.

 

[CNC Dan]

If you have a hard rubber fuel line replace it. It could be shedding rubber flakes. Get yourself a can of "sea- foam" to add to the tank. And get some disposable fuel filters to add to the fuel line untill everything gets cleaned out.

When it died after running, did it re-start?