Question on lpg dual fuel

[Clance]

Hi Guys & Gals, Can anyone tell me what mixer, regulator, solenoids, electronics are needed to put the dual system into my motorhome? Parts numbers would be really handy if possible.   
Thanks
Clance

[ben]

is your van already on gas??

cause id go for a kit fella.. if i was buying new.  otherwise you already have a kit if you buy second hand or getoff another vehicle.

dont know how youll go buying the kit not bing a certifyed gas person.. i tried to get some new gas line for black beddy but the guy hung up on me after he asked me if i was certifyed and i said no.. but see how you go. or get someone who is in the business to get ti for you..



good luck
cheers
ben

[Clance]

Thanks Ben,
No it's not already on gas, all the bits (supposedly) were with the moover when I bought it. I've since asked so many people about the gas system and had a million (so it seems) different replies and combinations of parts. I was just hoping that someone on here has done a conversion on a 350 chev for dual fuel and new the right/best combo of bits. I guess I'll have to bite the bullet and just take it in to get done!
Trying to get things done before the move back north, I'm meant to start work in Mackay mid october so now it's all happening at once! Rush rush rush!
Cheers,
Clance.

[Warren]

Clance have you considered running straight gas.

I would think you would have enough room for tanks under the van.

Ask 10 people and get 12 answers

A breif description of LPG system.

LPG stands for Liquid Petrolium Gas and as the name implies it is stored under pressure as a liquid until it is converted to gas for burning.
The conversion proccess causes a temprature drop at the conversion point.
Gas and petrol have different timing requirements as LPG is slower burning.

The components break down into:


Tanks
Lines
Solenoids
Control
Converter
Throttle Body / Carby


Tanks

You need to have enough capacity to get to the next fuel stop.
Not a problem in the Metro areas, but if your going bush, can be an issue.
Shapes and sizes vary, common are the cylinder, doughnut and scuba types.

Lines
Gas line has to be large enough to supply the converter, usually 3/8" dia.

Solenoids
Stop and start the flow of gas/petrol to the engine.

Control
Responsible for controling the soleniods, and in some cases the timing curve of the ignition system.
Usually a small black box mounted under the bonnet.

Converter
Converts the liquid to a gas and regulates the gas pressure. The converter requires plumbing into the water sytem of the motor to stop it Freezing. 

Throttle Body
The thing that regulates the amount of gas being delivered to the engine, in dual fuel setups it is normally the carby.


The main thing is that the lines can supply enough liquid to the converter, and the converter/regulator can create enough gas for the size of motor, from memory its rated in cubic feet per minute (CFM) the bigger the motor, the greater the CFM requirement.

I have seen 350's with two converters to supply the needs of the high performance engines.

You should be able to mount your tanks, converters etc, and then have a qualified Gas fitter do the instilation (plumbing etc)

Often it is best left to the experts to do this, but knowing a bit about it helps your Bulshit meter work.
   
Warren



 

[Clance]

Thanks Warren,
I have a pretty good understanding of the basics of lpg, just not the finer parts. As you said ask 10 get 12 different answers! The tank is already mounted and I have a convertor and a few other bits that came with the moover when I bought it but I don't know if they are suitable for the 350!
I have looked at the Impco site and downloaded heaps of info but I haven't found much on doing dual fuel on a 350.
I'll work it out in the end!
There are only 2 lpg gas fitters in southern Tasmania which makes me want to source the bits elsewhere!
Two heads and two fuels seems to lead to confusion!!

[Marishka]

hey Clance, if ur going dual fuel, i would remove the mechanical fuel pump fit a plate and install an electric fuel pump, that way it shuts down when switched off, unlike the mechanical one that keeps pumping when fuel is cut via solenoid,
marty

[ben]

why is that marty? is there anything wong with the mechanical pump pumping nothing lol?

[Clance]

Good idea Marty, I'll do that for sure. some sort of self priming one would be the best hey?
Cheers
Clance

[Marishka]

why is that marty? is there anything wong with the mechanical pump pumping nothing lol?

i just recon its better, why have a mechanical one pumping for nothing, mustnt do the inside of it  anygood, might even perish the valves or diafram , then when u really need it she,s cactus. plus u getaway with 1 less solenoid.

get a good elec pump though , like a holley or the likes.
marty

[Clance]

Yep, roger that! I used to do the same on my old rally cars, mind you just for reliability.
Clance