Community Forums

cimplexsound · 09-26-2018, 03:35 PM

Quote:

Originally Posted by Skiddy

50 hr oil change

no need for a primer bulb if it has an electric fuel pump

Some models of Onan's don't require a prime. On my mine you do have to prime the fuel up to the fuel pump then it will work beautifully. On the original factory manual you'll find that Cummins recommends oil change every 50 hours of use on most of the Emerald gensets. However keep in mind, unless you do a lot of dry camping, 50 hours is a lot on a generator, and many RV owners will never put nearly that much time on them.

Challenger19 · 11-03-2018, 05:12 PM

Hi; First post after lurking for quite a while. Some important info; Yes, I have researched the owner's manual and the installation manual and the wiring diagrams; the MH is new to me and the 4K Onan generator has 275 hours on it. It is a KY series and once started it runs great. I have changed the oil and the air filter and I have ordered a fuel filter which should be here by Thursday- 11/07/18. When I change the fuel filter I want to replace the spark plug.
Herein lies my predicament: I cannot find a listing for the proper plug to be used. Today I removed the installed spark plug and found that it is a Champion- RN14YC. From other Onan/Cummins generators, I remember that an NGK plug is preferred. Can someone point me in the right direction to find the plug I need? Thanks in advance. Ed

Redapple · 11-04-2018, 05:02 PM

I purchased NGK BPR4EY for my 5500 Marquis Gold

bigchick · 11-04-2018, 06:17 PM

okay, i'll bite! my experience is with an onan 5500 lp fueled generator. no experience with fuel pumps, filters, carbs, sta-bil, etc.

but my question has to do with the statements that the onan generators make 'clean' power. they are not inverter generators. they relay upon the governor to regulate the rpm. the rpm (i thought it was 3600 rpm but i may be wrong) is directly related to the frequency of the output power wave. i hear ours stutter a bit when a load gets switched on. plus i see the regulator arm move up and down. so i would expect the power frequency to vary as loads come online and offline. so i just wonder how 'clean' the output power wave is. i would think that inverter generators would produce 'cleaner' power than the mechanical onans.

Redapple · 11-04-2018, 06:29 PM

Rpms is based on the size of the engine

twinboat · 11-04-2018, 07:03 PM

Most gas engine generator heads are 2 pole and need to turn 3600 RPMs. 3600 RPMs = 60 HAs.
Some use larger engines so the can run the engine slower and overdrive the head. The lower RPMs quiet them down. My old Generac 5500 was belt driven and the engine turned slower then the generator head.

Diesel engine powered generator heads are typically 4 pole, so the engine can run at 1800 RPMs.

psandoz · 05-23-2019, 08:19 AM

I hope I'm not ambushing this thread, but seems to be a lot of generator knowledge here so I thought I'd look for suggestions. I have a Onan LP 6300 genset built about 1999. The generator has run fine, and in the last few days I fired it up before a trip and it worked fine. Went to start it yesterday and it is DOA - start button in coach and on the unit same thing - won't crank, nothing. Butane tank is full and there is 12 v at the lug nut to the generator. Someone suggested low oil, I checked and it was low, so I added oil and it's at full level - still nothing. Suggestions what else to try? Thanks.

twinboat · 05-23-2019, 08:41 AM

Quote:

Originally Posted by psandoz

I hope I'm not ambushing this thread, but seems to be a lot of generator knowledge here so I thought I'd look for suggestions. I have a Onan LP 6300 genset built about 1999. The generator has run fine, and in the last few days I fired it up before a trip and it worked fine. Went to start it yesterday and it is DOA - start button in coach and on the unit same thing - won't crank, nothing. Butane tank is full and there is 12 v at the lug nut to the generator. Someone suggested low oil, I checked and it was low, so I added oil and it's at full level - still nothing. Suggestions what else to try? Thanks.

Look for a small fuse holder on the control panel. Sometimes its just the cap with a fuse behind it.

If That's not it, check the ground cable from the generator to the RV chassis.

svcattales · 05-23-2019, 11:35 AM

This thread is good timing for me. I just started my Onan 4000 (KY) gas generator for its monthly exercise. It has been running great, but this time after starting the engine started surging. I could see the carb linkage going in and out (appears to be the throttle). After warm-up I turned on the AC and it did function, but generator still surged. I grabbed throttle linkage and it stalled out so I shut off AC. I restarted gen and it ran smoothly with no surging. I turned the AC on again and it ran fine, but gen started surging again. Next I turned off the AC and gen ran smoothly again. After a few iterations of this test, the gen ran smoothly with no load, but surged with a load from AC.

One of the previous post suggested adjusting the governor. Is that a good starting point or do symptoms suggest something else? Greg

PS. I have replaced fuel pump, fuel filter, air filter, oil, and spark plug recently and gen has been running well until today.

svcattales · 05-23-2019, 12:54 PM

Quote:

Originally Posted by svcattales

This thread is good timing for me. I just started my Onan 4000 (KY) gas generator for its monthly exercise. It has been running great, but this time after starting the engine started surging. I could see the carb linkage going in and out (appears to be the throttle). After warm-up I turned on the AC and it did function, but generator still surged. I grabbed throttle linkage and it stalled out so I shut off AC. I restarted gen and it ran smoothly with no surging. I turned the AC on again and it ran fine, but gen started surging again. Next I turned off the AC and gen ran smoothly again. After a few iterations of this test, the gen ran smoothly with no load, but surged with a load from AC.

One of the previous post suggested adjusting the governor. Is that a good starting point or do symptoms suggest something else? Greg

PS. I have replaced fuel pump, fuel filter, air filter, oil, and spark plug recently and gen has been running well until today.

I did a check on YouTube and found a video that shows how to clean a generator carb using Sea Foam/gas mixture in a gas can. You disconnect your main tank fuel line and attach an alternate fuel line into your gas can. You run the Sea Foam mix for 1/2 hour and then let it heat soak in carb. Here is the link:

https://www.youtube.com/watch?v=C6JEiGbR01A

Anyone try this? I'm thinking it is a good place to start rather than messing with the governor. What do you think?? Greg

twinboat · 05-23-2019, 01:26 PM

Quote:

Originally Posted by svcattales

I did a check on YouTube and found a video that shows how to clean a generator carb using Sea Foam/gas mixture in a gas can. You disconnect your main tank fuel line and attach an alternate fuel line into your gas can. You run the Sea Foam mix for 1/2 hour and then let it heat soak in carb. Here is the link:

https://www.youtube.com/watch?v=C6JEiGbR01A

Anyone try this? I'm thinking it is a good place to start rather than messing with the governor. What do you think?? Greg

Yes, try treating with the sea foam.

Its not a governor issue. Messing with that will just make things worse.

The governor controls the air/fuel going into the engine depending on load.

A dirty carb jet leans out the air/fuel ratio and causes the surging.

psandoz · 05-23-2019, 02:41 PM

Thanks Twinboat, I checked the fuse (slowblow) it is is fine. I'm really scratching my head on this one.

hivoltage98 · 05-23-2019, 02:48 PM

If it’s surging it’s most likely the carb. Try the sea foam and clean the carb. These carbs suck and are unfixable. You can try the seafoam, and carb cleaner, you can even take it out and try an ultrasonic cleaner, but you might have to buy a new carb. I tried all of this and then broke down and bought a new carb. Problem solved.

svcattales · 05-24-2019, 03:49 PM

Thanks again Twinboat! Your advice is always right on target. Also, thanks to Hivoltage for the reassurance on the carb being the problem.

I used the Seafoam video procedure to clean the carb. I started the generator this morning and it ran smoothly until I turned on the AC. Generator started surging again so I turned off AC and started the Seafoam treatment in the video.

I blocked off the main fuel line by squeezing it with vice grips before disconnecting it from the generator. I used the 2:1 ratio of gas to Seafoam so for me that was 2 pints of gas for 1 pint of Seafoam. Three feet of ¼” i.d. fuel line was a good fit on the hose barb of the generator so didn’t need a hose clamp. I primed the generator to suck fuel up into the carb from my jug and then started the generator. After about 20 minutes of running I still had about half my fuel mix left so rather than shut it down to “heat soak” the Seafoam mix I decided to turn on the AC again. To my surprise there was NO SURGING AT ALL with the AC running so I left the AC on and ran generator for another 20 minutes.

I let the Seafoam stay in the carb for about 4 hours and ran the gen again after hooking up fuel line to main tank. The generator started quickly and once again did not surge with the AC turned on.

We are leaving on a 3 week trip next Tuesday so that’s a big relief since we plan to do some boondocking. I love it when a plan comes together!! Greg