LP engine starting problems and regulator questions

I have a JLG manlift with a ford engine running on LP. This winter trying to work on shop addition, it suddenly wouldnt start. Has always had issues idling, no mater where idle speed is adjusted. Anyway, finally wamred up and had some time to work on it abit and seems like engine is cranking good, just not getting fuel. I checked the LP solenoid and it works properly. Pulled LP regulator and took it apart to make sure diaphrams were intact. It has Beam 120A regulator. There was alot of oil in it on the low pressure side where the hose to the intake manifold is. Is the oil why it wouldnt start and whats causing it? Seems like maybe the cold temps when I was trying to run it maybe condensed the oil out of the LP, but I thought usually it was so small amount it just got pulled through and burned up. This seems excessive.

I'm going to buy a repair kit for the regulator and probably some new spark plugs for the engine, but wondering if anyone here had any info on this stuff as I have not worked on LP engines much.

Oh and the gas side of the manlift hasnt been used in so many years its all gummed up and bad old gas etc, not even going to try to mess with that. Like the LP better as we have a liquid fill on our bulk tank and fill our own forklift bottles.

Edit: I figured this was right forum as its basically same as forklift engine problems. Move if you think there's a better place.

They put a small amount of oil in propane, I guess to help with corrosion. I have seen it collect inside vaporizers and gum them up before.

We've also had problems with dual fuel setups before. I found it best to get it running good on propane and leave it alone. Propane won't gum things up like gas and will last a lot longer and not go bad

Have you checked the water level in your radiator? The evaporator uses water from the cooling system. I have a Clark lift that shuts down when the coolant level drops.

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You are not alone.
Neighbor has a man lift with what is basically a Ford 4 cylinder overhead cam industrial version of the Pinto engine.
It's old, but new enough that it has a computer and no distributor. Only the LP side is used. Runs like crap, stalls, hard starting, shuts down unpredictably. Narrowed it down to one of the 2 'black boxes' onboard. Factory says it's obsolete, new replacement version is $1600, no returns or warranty.
That stalled the repairs.
So it sits, unusable.

Well I got a repair kit ordered, hopefully that will fix alot of it, will probably throw some new plugs in as well.

Yes it has atleast one "black box" controller, plus the weird electronic throttle assembly that has other crap in it too. Seems to run good when it runs, just idles crappy which perhaps the rebuild of regulator will help with, plus adjusting that as well. I'm leaning to it was January when it quit working all together, thinking that oil condensed out of the gas at the cold temps, and then was thick and plugged up the little valves in the regulator as well, causing the no start issue. I didnt try starting it in warmer weather yet as I already had it partially torn apart.

I can't offer any helpful information, but I do have a comical story to tell about mysterious "black boxes" on equipment.

A clever friend of mine has built welding machines over the years that used Chrysler style alternators as the welding power source, driven by gasoline engines or electric motors (gas for portable use, electric motor for in the shop.

He'd build them for his own use, and when people would see them they'd invariably want one of their own.

When he'd build one for a customer... he'd take a discarded Mopar voltage regulator (a metal box) and gut it...then fasten 5 or 6 random colored wires to the inside of the box, then fill it with a "potting" material of some sort... which is opaque, to cover the wires. Instant one of a kind "control module"

These wires from "black box" would be attached to various points of the simple welding current control system to give the appearance that this was some sort of high tech special module that was necessary for the operation of the welder.

Didn't do anything, but if anything ever went wrong with the machine, they'd think it was this "module" and would come bringing that box back to him to see if he could help him because no parts store could provide them one or had any idea what it was.

JP, I'd suggest doing a good tune up on the engine after you rebuild the regulator. I only say after so that you can see if the regulator rebuild changes anything before you swap other parts. Anyway, my lift starting acting like it had dropped a valve, running terrible and I was thinking the worst. It has always ran decent except for once a couple years ago it quit on me. Found burned points, replaced them and it ran great until a little while back when it started this mess. I figured a tune up would be worth trying before I dug any deeper and did all the ignition parts and it turned into a new forklift, runs great and smooth again.

That is why I suggest a tune up, it seems to me that LP engines are affected more by poor ignition than when on gasoline.

Jason

Agree completely.....
A "fuel" problem on an LP forklift (slant 6) got the best of me for several days till I finally figured out it was the Accel super duper coil I installed about 4 weeks prior, so it'd have a nice hot spark......yea right.....pile of junk.
It would run fine for an almost exact time (like 2 minutes and 28 seconds) till the coil got hot or whatever, then shut off and need a cool down of 15 minutes before it would restart. Fixed it with a Chevy HEI distributor. No problems since.

Like they say, 95% of fuel problems are ignition related.....


The "black box" machines aren't that simple to retrofit with aftermarket parts. And you can't just bypass things, even if you wanted to. I think the throttle and other aspects of engine operation are tied into the controls and safety circuits.

macgyver said:

JP, I'd suggest doing a good tune up on the engine after you rebuild the regulator. I only say after so that you can see if the regulator rebuild changes anything before you swap other parts. Anyway, my lift starting acting like it had dropped a valve, running terrible and I was thinking the worst. It has always ran decent except for once a couple years ago it quit on me. Found burned points, replaced them and it ran great until a little while back when it started this mess. I figured a tune up would be worth trying before I dug any deeper and did all the ignition parts and it turned into a new forklift, runs great and smooth again.

That is why I suggest a tune up, it seems to me that LP engines are affected more by poor ignition than when on gasoline.

Jason

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Some aerial equipment has a dual fuel set up.
It always seems to be a compromise at best.
If yours has a gasoline carb and not some sort of fuel injection, you may think about putting a LPG only system on it.
I have done it a couple of times.
I used Impco parts and pieces.

1+ for IMPCO over Beam