propane powered generator hard starting

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"Hard to start" implies that it does start.  If it runs okay once started, I would suspect air in the gas line.  If you restart it shortly after shutting it down, does it start quickly?  Try lighting the gas range briefly before starting the gen.
 
Look closely at the tube connecting the fuel regulator to the venturi (where the carburetor on a gas engine).  The regulator relies on venturi vacuum to pull on the regulator diaphragm and admit fuel to the engine, and vacuum is low while the engine is slowly cranking.

A slight pinhole or loose clamp on the tube can leak enough vacuum to make it hard for the engine to unseat the diaphram while cranking.  Once it's running at a higher speed the engine produces more vacuum and overcomes the leak.
 
Also, there is likely a tube running downward from the "Carb" which has an open end if not fitted with a screen, which in 2006 they were not. Bugs nesting up this can cause hard starting or no starting. This a vent pipe, and cost an hours labor to flush for a minute or two and rinse the bugs out for me.

After considerable discussion with ONAN, they refunded my cost. I reasoned that if they knew about this (they did) and had told me (they did not) I could have fixed the problem (which I did) without engineers making a study and inventing a screen and nylon tie (which they eventually did), and saved me the cost. Persistence paid off, even though they were a bit reluctant.
 
Molaker said:
Try lighting the gas range briefly before starting the gen.
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Might not help much as you have two valves on your propane tank. Liquid valve for the generator and gas valve for everything else. Make sure the liquid valve is completely open.
 
Wizard46 said:
Might not help much as you have two valves on your propane tank. Liquid valve for the generator and gas valve for everything else. Make sure the liquid valve is completely open.
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Guess there are LP generators then there are LP generators.  My Onan 2.5kw does not draw from liquid as best I can tell.  The tank only has one valve.  It could be a difference in size that dictates this, I suppose.
 
Yes, the problem is propane vapor is very cold when it boils out of the liquid propane, so you can't draw off too much at once or you'll drop the tank temperature (and pressure) or freeze the output line.

Liquid propane is 270 times more dense than the vapor, so you can draw out much more energy in liquid form without chilling the tank.
 
Just to be clear, some generators draw liquid propane from the tank and vaporize it in their "carburetor" as it mixes with air before entering the combustion chambers. Others draw vapor propane (at high pressure, not via the house regulator) and just do the mixing at the genset. I suspect, but do not know (without the genset model number), that the genset in a 2002 Journey runs on vapor. Often the genset has a separate line to the LP tank, but sometimes it is a "Y" fitting in the main LP line before it reaches the house LP regulator.
 
Onan propane generator hard or slow to start. I had this problem and made an adjustment on the propane regulator. There is a small red plastic knob that can be adjusted in or out. I turned it in a couple of turns and that seemed to help it.
 
stephen6426 said:
Onan propane generator hard or slow to start. I had this problem and made an adjustment on the propane regulator. There is a small red plastic knob that can be adjusted in or out. I turned it in a couple of turns and that seemed to help it.
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The OP hasn't been active here on the forum for 1 year. They never got back to us as to how they fixed their problem. Here's a case where a poster has a problem, the forum members give possible remedies and we never find out what worked. So please, if you have a problem and the forum members help you solve it, please get back to us with the solution for your issue. It may help others later on. Thanks and safe travels.
 
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