Generator won't start

[Dungrace]

Just got my Interstate back from dealership after a month for replacing the house batteries and now my gen is not starting. Any advices on how to get it to start? I still have half a tank of propane and checked all the switches are on and still can't start it. Im tired of bringing it back for service and have to wait for the dealership to get parts to replace it. I feel like I get something repair then something else is broken.

[Lily&Me]

Start your engine, be sure your propane is on, prime once or twice, then try.

Your house batteries may not be fully charged, too, or not enough to get the gen going.


Maggie

[DKB_SATX]

I've no experience with the Interstate, but useful info for people who do would be to tell them whether it cranks but doesn't fire, does nothing at all when you tell it to start, or tries to fire but never successfully gets running.

[Protagonist]

Originally Posted by Dungrace

Just got my Interstate back from dealership after a month for replacing the house batteries and now my gen is not starting. Any advices on how to get it to start? I still have half a tank of propane and checked all the switches are on and still can't start it. Im tired of bringing it back for service and have to wait for the dealership to get parts to replace it. I feel like I get something repair then something else is broken.

I had that happen to me once. Turned out the generator's voltage regulator was fried. Literally. The Cummins/Onan dealer showed me the one they removed, and it was scorched.

What would happen is that the generator would crank just fine on the house battery, but as soon as it caught, I released the switch and the generator immediately defaulted to getting spar to its spark plug from the generator's voltage regulator. But since the regulator wasn't working, no spark. Net result, it would crank and crank, but never really start.

Your generator might have the same problem. Or it might have a different propblem such as a bad spark plug or spark plug wire.

It could also be low on oil, since there is a sensor that will prevent the generator from running when it's low on oil. New Onan generators do tend to use more oil until they're broken in (first 25 hours of run time), because it takes a while for the piston rings to properly seat themseves, among other things.

Forget taking it to the Airstream dealer. Find your nearest Cummins/Onan dealer and let the experts look at it.

[avanti]

Assuming that it is cranking but not firing, by far the most common cause of an Onan genset problem is insects crawling up the little rubber vent hose and clogging it. They love it up there for some reason and it will absolutely not run if it is clogged. I know, I didn't believe it either, but it has happened twice to me. Just stick a thin wire up the tube that is hanging out the bottom and clean it out.

[avanti]

Also, are you getting an error code? You read a pattern of flashes on the light on the starter button and look it up in the manual.

[Lily&Me]

Originally Posted by DKB_SATX

I've no experience with the Interstate, but useful info for people who do would be to tell them whether it cranks but doesn't fire, does nothing at all when you tell it to start, or tries to fire but never successfully gets running.

Very good, David!


Maggie

[Ron_CA]

Is it cranking?

No need to prime on your propane generator, ignore that switch.

[Lily&Me]

I hope she comes back to tell us if it started, and what worked.


Maggie

[InterBlog]

Originally Posted by Lily&Me

I hope she comes back to tell us if it started, and what worked.


Maggie

Me, too. We had this problem very early on but it turned out to be pretty simple - not enough life left in the coach battery. Lights would work but it wasn't enough to fire the generator.

[73shark]

Originally Posted by Ron_CA

Is it cranking?

No need to prime on your propane generator, ignore that switch.

I wish Airstream would just put a piece of black tape over "Prime" like I did. It just confuses us unwashed masses.

[Dungrace]

It cranks, but it won't start. Time For it to go back to service again for more warranty repairs. The tech guy told me that we don't need to prime the gen because it's running on propane and there are no error codes.

[UKDUDE]

Asking the obvious, but have you made sure propane is actually flowing by lighting a burner?


Sent from my iPad using Airstream Forums

[avanti]

Originally Posted by Dungrace

It cranks, but it won't start. Time For it to go back to service again for more warranty repairs. The tech guy told me that we don't need to prime the gen because it's running on propane and there are no error codes.

Well, I repeat: Over an 8 year period, I encountered and fixed this precise problem TWICE by cleaning out the vent tube. Not saying that is your problem, but I would think it would be worth the 5 minutes to find out.

This is not hearsay, it is first-hand advice. If you don't believe me, here are a few random citations:

Cleaning out the regulator vent hose on your RV's Onan MicroQuiet 3600LP generator may solve staring problems

LP Generator problem [Archive] - Sprinter-Forum

http://www.justanswer.com/small-engi...test-fine.html

[73shark]

I'll have to recheck mine but I believe it has a foam filter on the end of the hose. I always wondered what it was for.

[mrcolin2u]

Just had this problem of not starting I found this thread and inserted a metal tent peg into the vent pipe I saw some spider webbing on the end of the peg when it came out of the vent hose and the generator started first attempt .
This is a great site that has helped me solve a few problems with my van .
Thanks
Colin

[solar-guy]

Thank you Thank you Thank you !! The generator on my 2008 Interstate quit a couple of weeks ago and your tip on the plugged vent hose solved my problem in about 1 minute... The mud wasps had plugged the vent, when I cleaned out the mud the generator started instantly! I need to read more of the thread to confirm what that vent actually does.

thanks again!!

[BurntAsphalt]

Originally Posted by solar-guy

Thank you Thank you Thank you !! The generator on my 2008 Interstate quit a couple of weeks ago and your tip on the plugged vent hose solved my problem in about 1 minute... The mud wasps had plugged the vent, when I cleaned out the mud the generator started instantly! I need to read more of the thread to confirm what that vent actually does.

thanks again!!

Avanti,
Count me among the grateful folks that found your solution to the "Onan genset cranking but not starting" issue!! Looked under the bus and the vent hose was plugged by a mud dauber just like you described. Thanks!!

[weather command]

Another Grateful one!! Worked for me!!!! Now, trying to figure out AC unit...started to make thumping noises and stopped working😒

[Moereece]

Does anyone have any pics of where this vent hose is?Thanks