Lil' help needed with LP Generator

[8thDegree]

I have another problem that I could use some assistance with. It concerns my LP generator on my 97 Dynasty. I have never worked with any motor that is run off of propane, thus my need for help.

Background: When we purchased the coach and drove it from Oregon back to Texas over the July 4th weekend, the generator worked fine. On our first trip several weeks later, it was hot so we cranked it up to turn on the AC for the drive and about 10 minutes before our destination, the generator shut off. I did not worry as we were able to plug in a short time later.

When I got it back and took some time to look it over, it has spark and there is plenty of LP in the tank. I checked the air filter and the oil and both have recently been serviced. However, I was unable to get it to crank so after a while I sprayed some starting fluid into the carb and it started right up. I let it run for about 30 minutes and turned both ACs on to make sure that the load was not what was causing it to die. It ran fine.

Over the month of August I was working on my leveling jacks which forced me to open the generator slide, so I would always try to crank it. I could not get it to crank. The choke does engage after a second or two of trying to start but it would not start on its own. However, every time it would start with a bit of starting fluid. Also, it would always run fine after starting.

This past weekend we took a trip and about half way to our destination it got hot so when we stopped for lunch I put out the generator slide and had starting fluid in hand. Went to crank and it fired right up on its own. Ran for several more hours that day running both ACs without fail. On the way back, we needed to turn it back on and it did not want to start. I sprayed starting fluid and once again it fired right up. After firing up both ACs and running for about 5 minutes, it began to struggle to stay running and then it cut off. I drove for another hour or so and then we stopped for lunch again. I opened the slide and sprayed the starting fluid and it began running smoothly. I ended up turning one the front AC only and it ran fine the rest of the trip home. When we got back to our storage we left the generator running while unloading and I turned back on the second AC unit and it continued running for 15-20 more minutes until I shut it back down.

I have read the owner's manual and looked online for help, but there is not much information about the LP fuel system. Most info that I can find on these generators have either gas or diesel as a fuel source. That is what I am suspecting, but I am open to any suggestions. I know it has a carb like a gasoline engine. Does these need to be rebuilt or cleaned? Again, don't know about LP as a fuel source.

Thanks for any suggestions you can give me on how to get this working 100% of the time!

[Pa Miller]

Been thru it with my LP , You need to get under the unit and find the LP pressure reg not sure thats what its called . but it will be at the back drivers side of the gen... Get a light and look up past the muffler and you will probably have a dirt dabber nest in the vent on the regulator you can see the round vent hole it is at the top of the unit !!! I just jerked my LP unit out and ordered a diesel unit #$%$$@#$ and there was a dirt dabber wasp nest in my #$%$## vent !!!

[Old-Biscuit]

Check the Gen LP Regulator VENT Hose.......it MUST be free/clear

Here is an example


Vent hose attached to Gen LP Reg


Vent hose allows air to move in/out of LP Reg body on top of diaphragm as diaphragm moves to control propane flow/pressure
If vent line clogged...insects/deteriorated hose etc diaphragm can not move properly

Just something simple to check.....

[Pa Miller]

[QUOTE=Old-Biscuit;3792358]Check the Gen LP Regulator VENT Hose.......it MUST be free/clear

True but ours don't look nothing like that and is under the gen cover at the very back rear upper above the muffler you can stick a wire up there but thats about it ! Other than pull the gen.

[8thDegree]

Thanks for the info everyone. I will check it out this weekend.

Pa Miller, can you disassemble the generator cover for better access? Or, could you possible blow it out using compressed air?

One other thing; if the vent hose has some type of insect nest, would it still run normal (at least most of the time) after it gets cranked? I guess it has been a little inconsistent so it very well could be. Again, I have never had a LP engine, so I am curious as to what you all think.

My other question is about the LP carb. Do they ever need to be cleaned or rebuilt like a gas carb? Very curious about this as well.

[Pa Miller]

If you can take the top off it would be easier to see , On mine also the governor rod had came lose (right on top of the motor) and it was simi working too .. If you lay flat on your back and look strait up passed the muffler on the driver side you can see the bottom of the regulator and the vent hole is facing down on mine so a long wire would clean the dirt dabber out of your vent line without removing... good luck

[oldmattb]

We had a slightly older RV with a propane generator and similar symptoms. It was the pressure regulator on the generator, clogged with oil and gunk.

The Onan part was hundreds, and was recently discontinued. I spent half a day on the web and discovered that the specs for the $300ish Onan part, and the $19 forklift regulator on Ebay were identical.

I hope this helps.

Matt B

[8thDegree]

So I went to the motorhome today to look at the generator. I pushed it out of the front and looked underneath like Pa Miller had suggested but I did not see any type of insect nest. To be honest, I am still not quite sure exactly what I am supposed to be looking for. Here are several pictures of what I was looking at next to the muffler. These were taken from underneath the generator looking up from the rear drivers side. I turned the flash on, but you can tell I did not get very good pictures.







Is this where I am supposed to be looking for the pressure regulator?

I "think" there was something very dark at the top which appeared to have a hole in it. I did reach up with a coat hanger and believe it was metal. Would this pressure regulator vent hose be metal, or rubber?

I looked as best I could around the whole unit and did not see nest of any type. I thought about trying to remove the metal cover, but it looks like a bear. Several bolts on the bottom you can't even get access with a socket and will have to use a wrench (which I did not have with me).

I also tried to crank it again and ran into the same problems as I wrote about earlier. Any other advice or suggestions?

oldmattb, do you have a 98 Windsor? If so, we might have the same generator (I have a 97 Dynasty). What was the part number you mentioned you found on ebay for the forklift pressure regulator? Also, do you have any advice or directions you could share about how you replaced it?

Thanks again for everyone's assistance!

[clyon51]

For what it's worth, propane has an oil in it. Over the years I've had to clean out the LP regulator several times as the build up of oil caused an erratic flow to the LP appliances, causing them to fail as designed. Can't help you find the regulator, but It's a good bet that is your problem. Good luck!

[Pa Miller]

Ok in the top picture the silver round thing is your regulator it appears your vent hole is on the right side of the regulator mine faces straight down.. It will be nothing but dirt packed into the vent hole.. THere should be a plate on the drivers side of the generator you can remove and see the regulator . Id you can remove the top cover from the generator it would help and you could see your gov linkage it can come lose and it will do the same thing ...

[Pa Miller]

Originally Posted by clyon51

For what it's worth, propane has an oil in it. Over the years I've had to clean out the LP regulator several times as the build up of oil caused an erratic flow to the LP appliances, causing them to fail as designed. Can't help you find the regulator, but It's a good bet that is your problem. Good luck!

That is true ... The regulator is on the back drivers side upper corner... you have to remove the top to get to it... it has tubes running to the egt pipe that turns the LP to vaper ..

[Pa Miller]

These gen run at 1800 rpms and it doesn't change much at all when you add more draw after the unit is warmed up .... My gov linkage was completely unhooked and would run if you warmed the eng up for a while before loading draw on it.. But cold it would die tiring to govern the load . If you can remove the top you can check your regulator and linkage and hoses ... You'll get it ...

[oldmattb]

Originally Posted by 8thDegree

oldmattb, do you have a 98 Windsor? If so, we might have the same generator (I have a 97 Dynasty). What was the part number you mentioned you found on ebay for the forklift pressure regulator? Also, do you have any advice or directions you could share about how you replaced it?

That generator was in a 1994 Foretravel we no longer own. Our current 1998 Windsor has a diesel generator.

The part was replaced by a shop. I took it in for repair, and they told me "sorry, dude - part discontinued." That was what started my search. I no longer have records, but I remember it was easy to find, once I knew what to look for.

I am going entirely from faded memory, maybe a decade ago, but I think it was a Model J, like this one:

https://store.intellaliftparts.com/p...SABEgLVCvD_BwE

I hope this helps.

[8thDegree]

So I finally got the propane regulator out of the generator. I think I am going to get a kit to rebuild it but I am concerned that it is not hooked up correctly. Here are pictures of the removed regulator:

There were only 2 gas lines connected to it. At the 3 o'clock position, you can see some foam rubber that goes around another fitting. Here I have removed it:

My research has lead me to believe that these are controlled by a vacuum line from the carb. If not, then this line is open to outside air. In fact, when you blow on it, you can hear the diaphragm moving. If anyone could tell me how this is supposed to be hooked up that would really help. I think it is hooked up incorrectly and would like to see if I can't hook it up correctly.

Thanks for you assistance!