Propane experts

fixerupper · Jan 6, 2019

Son got his new to him forklift running today. It has a Continental flathead six on propane. It runs nice at speed but idlls like it is running rich. It sounds like it has a hot cam at idle. We know nothing about tuning the fuel mixture on a propane engine. Do you guys have any tips and suggestions?

Dieseltech · Jan 6, 2019

Try turning the turnbuckle between the throttle plate and gas valve, it may be too long or short. I have the same Century system on my Cockshutt 30.

37chief · Jan 6, 2019

The fork lift we have is about the same as yours. I wonder if the pressure regulator is letting too much fuel in. Shut off the fuel , and see if it runs better just before it quits. Stan

FBH44 · Jan 7, 2019

Yes, one suggestion, don't tune propane things indoors. The stuff deadens your smell nerves, to where you can't smell how much you have let loose, and is really does settle to a thick layer on the floor. I tuned up a propane water heater in a basement one time, went to light the thing, stuck a big kitchen match, and WHOOOOOMP a big blue flame ignited and rolled under my crotch and across the floor. Prettiest thing, it was a big blue waterfall rolling across the floor ??.. terrifying. Tune the thing outdoors, please.

mazemeister · Jan 7, 2019

I would first look at the demand regulator. Is it possible it is not closing all the way? it needs to shut off completely when there is no manifold vacuum. it could be leaking slow enough that it is too much fuel at idle, but opens normally at high speed.

fixerupper · Jan 7, 2019

The demand regulator is the regulator diesel tech advised to adjust the linkage to?

Dieseltech · Jan 7, 2019

No. The regulator uses engine heat to convert liquid to vapor. When regulator diaphragms go bad they leak, allowing so much fuel in engine won't run. Since yours runs, try adjusting the throttle plate to FUEL VAPOR VALVE, that's what controls idle mixture. Lengthen or shorten as needed for smooth idle. If no change then have the regulator looked into.

fixerupper · Jan 7, 2019

Thanks for the help. Will let you guys know what straightened it out when the time comes.

John Deere D · Jan 7, 2019

I'm NOT an expert:

I have ran and operated both IMPCO as well as Century Propane systems on several of my vehicles in the 1980's:

I would check as per picture:

455 Buick...460 Ford...429 Ford...292 GMC all were on Propane:

Bob..

Dieseltech · Jan 7, 2019

Doubt it's the electric primer, it's to help with cold starting only. Lots of LP engines even start fine cold without it. The Impco LP equipment I had on a 455 Olds Turbo years ago I never used the primer, ever.

MT pockets · Jan 7, 2019

Mr. Dieseltech has the correct answer here. Loosen the locknut on the turnbuckle and turn the knurled barrel of the turnbuckle whichever direction to smooth the idle out. Tighten the locknut and you are done. The engine needs to be up to operating temperature the you do this. Steve Norwood. Banner, Mississippi.

fixerupper · Jan 7, 2019

(quoted from post at 18:03:17 01/07/19) Mr. Dieseltech has the correct answer here. Loosen the locknut on the turnbuckle and turn the knurled barrel of the turnbuckle whichever direction to smooth the idle out. Tighten the locknut and you are done. The engine needs to be up to operating temperature the you do this. Steve Norwood. Banner, Mississippi.

I just talked to my son, turning the adjusting rod doesn’t help so I assume the regulator is next. He said the rod was turned completely one way so I’m thinking the po was trying to adjust this rich mixture out of it. The clutch is stuck and he found out it’s a wet clutch Andy the oil is brown from water. He plans to drain it and pour diesel fuel in there, run it a bit and let it soak. There is an inspection plate on the top of the bellhousing but he said it will be next to impossible to get down in there with anything to pry with.

Propane experts

fixerupper

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Dieseltech

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37chief

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FBH44

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mazemeister

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fixerupper

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Dieseltech

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fixerupper

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John Deere D

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Dieseltech

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MT pockets

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fixerupper

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