Cummins Onan ky spec p 4000 gas generator wont start

[Scott Parrish]

I’m going to throw this out like a hail mary see if anyone has ideas for me to try.
Short story. For the first time ever I was running the generator and my coach gasoline level was taken to quarter tank causing the generator to shutdown (i’m assuming). I filled the tank the next morning and went to use the generator and couldn’t get it started again.

Long story below

I have a 2014 coachmen motorhome with a gas cumins onan 4000 ky spec p generator.
The generator has always run for me over the last 2 years of ownership although starting did not seem smooth it always started generally on the second try after holding the prime/stop the first time until the light came on and counting to three it didn’t usually start the first try would generally start the second attempt. I’m in Florida now normally in Massachusetts.
So I ran the coach to 1/4 tank of gas and generator must of stopped while sleeping. I filled the tank the next morning but the generator won’t start now.
Oil level was low. I added oil.
I did prime for 30 seconds over multiple times now with no luck
Air filter is now brand new
Spark plug was pretty gunked up with black thick build up
Spark plug is now brand new and gapped with tool I was sent in a tune up package.
Oil has been changed and is fresh filled to proper level.
Gas tank is full.
Ground is level.
I took the carburetor out but it looks great no gunk.
I took fuel line off and ran a separate fuel hose into a 1 gallon gas can of fresh premium fuel with 8oz seafoam.
I also disconnected fuel line from carb and held prime switch and generator fuel pump works amazing, gas flow seems crazy strong.
Has anyone experienced this?

Looking for any advice and things to try.
Anyone know of a service manual website?

Thanks
Scott

[Hank not George]

Here's how I would tackle this since your oil level is up to par.

First, make sure the choke is working and closed when starting the Gen. I had 2 of these gens and the choke would stick open. if that doesn't get it started go to the next test.

Second, spray a little bit of Starting fluid into throat of carb to see if it will at least fire once or twice. If it fires, you more than likely have a fuel delivery problem. If you have a fuel delivery problem, you need to clean the jets in the carb. That requires that you disassemble the jets (esp the VERY small Pilot jet), and MAKE SURE you can see thru it. I usually use the smallest guitar string (E string which can be purchased separately). If the guitar string doesn't pass thru it, buy a new Pilot jet and install it.

Third, if it didn't fire check for spark. There is a low cost spark tester tool you hook to the spark plug if you are unable to view the spark with the naked eye. You said you put in a new plug, but sometimes even new plugs can be bad.

Fourth, If you have spark it is now time to check compression. Again, you can buy a compression guage and connections for about $25. Find out what normal compression is suppose to be and compare your results. If your compression is low, you have either a stuck, bent or gunked up valve, or you need a set of rings. Any one of those is very labor intensive.

Good luck

Hank

[Scott Parrish]

Thanks Hank
I will run through your list.
I’m in pompano Beach at the moment. It’s been pouring rain.
I’ll gather the supplies while waiting for some weather I can run through your homework list you gave me.
I appreciate your time
I’ll post results soon

[dm_callier]

When you disconnected the fuel line from the carb, did you test the gas flow through the fuel filter or without it? Are you sure about the oil level? On my Onan the proper way to check the oil level was to remove the screw cap, wipe, screw the cap all the way back in and then remove and check the level. I ask this because you mention you added oil initially. And there are manuals available online.

BTW, I'm shocked...shocked...that someone has actually asked an RV question and received an intelligent answer with no reference to politics.

Enjoy the day!

[Scott Parrish]

Haha DM, glad I was able to renew your faith in the forum.



I did check the line both ways. First I disconnected the line at the carb and put on a small line run to a gas can of premium fuel with seafoam I primed the generator and the gas FLOWED!!! BUT that bypassed the fuel filter.


Then I also primed the generator with that same original hose which has the filter inline to see if the filter was clogged but it had the same strong flow.

Yes. As I have become more familiar with the generator through this ordeal I knew the oil should be changed as well. I got 2 quarts and added some to raise the level of the old junk since I had a bit to play with as the oil change was to use only 1.6 quarts out of my 2 new quarts. I did check the oil in the approved manner.
Thank you for your help.

[Scott Parrish]

Hank
I just ordered my arsenal of spark plug tester, guitar string .011, compression gauge , and I will find starter fluid somewhere around here. Stuff gets delivered tomorrow

[dm_callier]

One last Hail Mary before you receive all your troubleshooting gear...for reasons I never bothered to pin down the 2.8K Onan in our Rialta would sometimes not start until we started the RV engine. I surmised the added amperage from the the alternator was the difference.

Like I said, Hail Mary...

[Hank not George]

On Thursday, December 12, 2019 at 11:15:26 AM UTC-5, Scott Parrish wrote:
> Hank
> I just ordered my arsenal of spark plug tester, guitar string .011, compression gauge , and I will find starter fluid somewhere around here. Stuff gets delivered tomorrow

I can't remember what the inside of the carb looks like, I've cleaned 100's of carbs. It may only have one bigger jet. But either way the jet(s) has to be removed to be cleaned correctly and all the ports blown out. Starter Fluid can be bought at any auto parts store.

I am not a big fan of Seafoam. I am a fan of starting all gas powered vehicles at least once a month to get fresh gas thru the lines. I'm not sure what causes it, but with Seafoam there is usually a brown muddy residue in the bowl.

Again, good luck.

Hank

[Dusty]

A good list and an excellent sequence. Well put, Hank. I'm gonna copy
and keep this one. Thanks again.

Dusty
--
"The ultimate result of shielding men from folly is to fill the world
with fools." -- Herbert Spencer

[George Anthony]

So why did you?

--
How can anyone see what's going on with the impeachment hearings with
all the smoke in the room.

[Scott Parrish]

DM I will entertain any and all suggestions
I did try that previously as well.
Anything I found on the internet that appeared pretty simple I tried.

Taking the carburetor off was kind’ve a pain. I imagine the next couple/few times I do it will get easier and easier.


Sincerely,

Scott Parrish

[Hank not George]

Thanks. There used to be a guy on here (Alan Robinson) that was a Generator Guru. I miss his posts. He really knew his shit. I learned a lot about Generators but still don't know enough of the real techy things.

Hank

[George Anthony]

On Friday, December 13, 2019 at 2:02:17 AM UTC-8, Hank not George wrote:

> Thanks. There used to be a guy on here (Alan Robinson) that was a Generator Guru. I miss his posts. He really knew his shit. I learned a lot about Generators but still don't know enough of the real techy things.
>
> Hank

The key is used to be! and you and your cronies traded something useful for something useless like politics, I suppose it is just part of the mental illness of you ilk.
http://www.msn.com/en-ca/news/newspolitics/trump-attacks-greta-thunberg-for-being-times-person-of-the-year/ar-AAK3K7F?ocid=ientp

--
How can anyone see what's going on with the impeachment hearings with

all the smoke and farts from Trump in the room.

[Scott Parrish]

Hiiiii. I’M BAAAAAACK but not in business.
I did run through all of my homework for this s@#tStorm
and my results are.
Original carburetor I took off, the gasket is pretty mangled... it could be my doing????
Then I lost the spring to the bowl thing as I was checking it to see if when I connect power to it that it moved up and down?? If you know what I mean. So I used lead wires. Conected it to my attery bank BUT ..... with short lead wires and the little pin just sits loose on a spring and a washer was there, too many pieces. I was concentrating on not loosing pieces and I short my leads against each other ⚡️Like an idiot. I scared my self and all the peices went flying. I had to rip my whole rv storage bay apart empty sll tool bags. I found the washer and the pin BUT the spring is now missing in action. Wasted like 45 minutes looking. It got dark.... the S@#tstorm continues.
So maybe it’s a success? The sring jumped out far away???

Sooo ... i check for spark spark plug tester glowed.

I now have a knock off carburetor on new gaskets.

I did clean the old one. Ran .011 guitar string through jets.
Maybe i can take the spring from the knockoff carb, I’m not sure.

Soooooo. I tried starter fluid. This should get some laughs.... i sprayed it. Tried to start. Got nothing.
So i tried one more time. I got something. A 🔥🔥 fire so now I’m like NO NO NO. I run around the other side of the coach release the extinguisher and pull the pin to put out my flambé style fire which only appeared to melt the wire loom.

Sooooo.

I put a compression tester on. I think I did it right. But it reads nothing.

[Frank Tabor]

Valve stuck open. Rod broken. Rod cap fell off. Gauge malfunction. Head
gasket blown.

[George Anthony]

If you have fuel to the cylinder and spark it should at least "pop".
However, with no compression you could have one of a few things wrong.
It could be a hole the piston, broken piston rings or a leaking,
bent or stuck valve (if you have absolutely no compression a leaking
valve is not likely). About the only way to tell for certain would be to
pull the head. Broken rings may not be obvious but the others will be.

--
How can anyone see what's going on with the impeachment hearings with

all the smoke in the room.

[Scott Parrish]

Sounds plausible
I have now went to justanswer.com.
We got the valve cover off. Valves open and close.

Spinning engine manually with a pencil inside does appear to push pencil down which means rod is ok... but then it gets stuck like it will get chopped off due to engine turning. So that’s where we left off. I’m waiting for next session i got a tool stuck inside the plug hole. It was a driver extension but it had a sliding screw dodad that covers a screw when your driving it in and I couldn’t get it back out for 10 minutes
I think my tech was crying or laughing so hard. Now he has family visiting 😂😂. Soo. I got the tool out.

I’ll keep you up to date with my crazy shiiithow. Thanks for the posts

[Scott Parrish]

Thanks.
Well. I made it pretty far along with trying to fix it economically
I think it’s going to have to go to a service center.
There’s one close by.
Unless my just answer tech support guy thinks we can do it.

[Hank not George]

Wow! After reading your latest, it looks as if you're having a little trouble. :-) I think every mechanic has gone thru what you are experiencing. It's a learning experience.

I am a little confused tho. When you sprayed starting Fluid into the carb did it act like it wanted to start even a little?

Also, I may be at fault for forgetting about the fuel shut off valve attached to the carb (it has one wire going to it). Please forgive me I'm old. I think that is what you mean when you say you lost the little spring that goes to it. The spring goes under the plunger, and there is one electrical wire attached to it, correct? If so, that may have been your problem all along. Also, you might want to make sure the is 12 volts going to the wire when you press the start button. This fuel shut off valve is nothing more than a solenoid that immediately shut fuel off to the carb to prevent backfires.

If it "fired" at least once, that means you have some kind of compression. Watch a video on utube to make sure you tested compression correctly. Did the aftermarket carb come with the electric fuel shut off valve? If not, get a new one. Most are inexpensive if you shop around. Usually under $20. Testing the old one may not produce any results if not done correctly.

I'll be waiting for the compression test results.

Hank

[Scott Parrish]

I don’t fail very often. With so much information available and sites like this it helps people like me.
I would like to thank everyone for their input.
I will update you on the ultimate issue. I was scheduled for Thursday afternoon at the local onan service center but got a call and someone cancelled .... so tomorrow at 8:15 we’re going in.

The starter fluid did nothing for me not even an inclination of wanting to start

Yes. Fuel shutoff valve.
The new one had it attached. So the lost spring on the old one was no big deal.

I suppose it could be possible the shutoff valve was shutting off my fuel however it works. If it’s possible it’s stuck or not getting power. There was definitely plenty of gas flowing when I checked that. Anyways the shop I’m going to seems pretty efficient I would be surprised if I am not up and running by tomorrow.

My compression results weren’t registrable so most likely user error. I gave it a shot.

[Scott Parrish]

Ok I’m here at the cool generator shop.
The tech took over the valve cover and to his trained eye saw the broken valve.
Although they did flap up and down so to my untrained eye all looked ok but one of the valve springs had a slight bow to it. I guess something that holds the spring on broke.
He said it was a common problem and if the generator was run more years ago it would’ve failed and been covered under warranty
So. I was getting closer to figuring it out but would I really have been able to fix it

[Hank not George]

First and foremost, Thanks for the update. Too many people post on here but we never hear back from them. I'm sure everyone in this group appreciates your feedback on your problem. It may help others in the future.

Sounds like the tech knows his shit. It will get expensive but it could've been worse and even more expensive if not repairable.

I'm sorry I couldn't help more.

Hank

[Scott Parrish]

You were great thanks for giving me suggestions. I feel I did my due diligence to save money and ultimately we will be full timing the generator is a fast way to juice our growing BattleBorn battery bank. They are very expensive with 400 AH we can get through quiet time running the AC if needed. Then rejuice them during the day. We are still hammering out our non suffering glamper lifestyle with tons of projects to get done everything uses electricity. Battery chargers for metal detecting gear, phones, watches, washer/dryer, dishwasher.
It was nice to meet you and we will check back.
My wife is a political nut. Once she gets a screen name she’ll have somewhere new to vent amongst some peers.

[Hank not George]

Nice meeting you too. The people on here are more than willing to help and there is lots of experience here also.

I hope your wife is thick skinned. The people on here can be brutal when it comes to politics. Anyway, good luck and tell us where you're at and what's happening.

Hank