Propane generator will not start without starting fluid

Kayteg1 wrote:

dieseltruckdriver wrote:
If you are outside next to your generator, reach around to the back of the air filter and cover the intake hole. You don't have to seal it, just block most of it. While holding your hand there, hit the start button, it will start easily. Mine did that for years, until I removed it and store my Hondas in that space.

That works well THANK YOU
I took a picture how I put silver cardboard to cover airbox inlet.

NRALIFR wrote:


Provided you don't have other issues with your gen, you will love the way the new regulator helps it start.



:):)

Thanks for the tip. Turns out the regulators come with prime button, that mine does not have.
I might spend $50 for new regulator in the future, but the above cardboard does the same job, while both options make remote starter a "hood ornament". What are the manufacturers thinking making build-in generator with remote start, but no remote prime :S

Get a new regulator now and be done with it.

I would NOT recommend choking manually with your HAND or having your hand anywhere NEAR the intake.. All it would take is for the engine to BACKFIRE ONCE and the result will be ugly!

dieseltruckdriver wrote:
If you are outside next to your generator, reach around to the back of the air filter and cover the intake hole. You don't have to seal it, just block most of it. While holding your hand there, hit the start button, it will start easily. Mine did that for years, until I removed it and store my Hondas in that space.

That works well THANK YOU
I took a picture how I put silver cardboard to cover airbox inlet.

NRALIFR wrote:


Provided you don't have other issues with your gen, you will love the way the new regulator helps it start.



:):)

Thanks for the tip. Turns out the regulators come with prime button, that mine does not have.
I might spend $50 for new regulator in the future, but the above cardboard does the same job, while both options make remote starter a "hood ornament". What are the manufacturers thinking making build-in generator with remote start, but no remote prime :S

If you are outside next to your generator, reach around to the back of the air filter and cover the intake hole. You don't have to seal it, just block most of it. While holding your hand there, hit the start button, it will start easily. Mine did that for years, until I removed it and store my Hondas in that space.

Kayteg, I had the same problem with my 36LP a few years back, and eventually discovered that the "regulator" on the generator wasn't operating correctly. That device is not really a regulator. It's more of a vacuum actuated on/off valve that is supposed to open when there is the tiniest amount of vacuum in the intake manifold. As it ages though, the rubber seat on the needle valve inside it gets sticky, and refuses to open when the engine is cranking.

Wouldn't it be great if there was a way to manually force the valve to open? Guess what......there is!

The OP in this topic had bigger problems with his than you do, but in my post you will find a link to the US Carburetion website regulator page. Buy the replacement for the KN regulator that has either a manual prime button or an electric prime solenoid.

After you install the new regulator, the way you use it is to push and hold the "Prime" switch on the generator panel with one hand, and then push the manual prime button on the regulator with the other hand. I usually give mine a couple of one-second shots, then hit the start switch. It cranks 2-3 seconds then starts every time.

Provided you don't have other issues with your gen, you will love the way the new regulator helps it start.

Post about KN regulator

:):)

Here's a link to the service manual:

https://www.generator-parts.com/manuals/generac-rv/0D1752.pdf

There is a section on the LP fuel system.

That is the thing. There is not much to it.
The carburetor has a butterfly to adjust the flow, but propane is introduced by like 1/8" nozzle with not much of calibration.
about a foot long hose leads to regulator. It is same type of regulator I know from scuba = you need to create vacuum to open it.
Than on main propane line I have solenoid that opens propane to regulator.
The "prime" button on the panel energize solenoid, what opens propane to regulator, but regulator holds the flow till the vacuum is created.
There is nothing I can do on regulator and I took it apart to prove diaphragm in good condition.
I used to have propane forklift and that had push knob on regulator, that would introduce propane into engine, but not on this Generac.
My feeling is that the engine is not creating enough vacuum to open regulator at start up.
Still it runs perfectly after fluid start up.
I check all hoses and all looks in good condition regardless 13 years.

It has been a long time since I converted gas engines to run on propane. The propane was delivered to the engine via the air intake system as a vaporized mixture. The carb became only a flow thru regulator via the throttle plate. There will be some mechanism for the propane vapor to be introduced to the air intake, perhaps by a vacuum switch. That will be the area to check for problems. Some systems had a primer that would allow an initial shot of propane vapor for startup and the vacuum would take over the flow needs after that.

You have a serious tuning issue IMHO. I would start with the spark and the carb. Cleaning and renewing thoroughly. Also look for vacuum leaks, damaged hoses, cracked manifolds, damaged battery wires. Just for fun, how is the oil? Propane units generally don't dirty the oil, but pull the dipstick and check the quality of the oil. Good luck.

I don't know squat about that generator but it's evident it isn't getting the correct fuel-air mixture to start. Is there a butterfly plate in the throttle body that would act as a "choke"? Also, ISTR that propane fueled engines may have a valve that allows higher propane delivery for starting.

For more focused advice, list the model and year made. Some of the really good generator techs will only respond with that info.