propane injection

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propane injection

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propane injection - 7/10/2007 6:54:52 AM

drc1231

Posts: 3
Joined: 1/10/2007
Status: offline

I own a 1977 240D ....would like info on how to install propane injection?

Post #: 1

RE: propane injection - 7/10/2007 8:09:01 PM

ForcedInduction

Posts: 672
Joined: 5/20/2006
From: Federal Heights, Colorado
Status: offline

The best info is don't.

Waste of time, waste of money, no significant increase in economy (When propane AND diesel cost are factored together), no significant increase in power (because of limited air), dangerous to the engine (too much can blow the headgasket), and it's dangerous to you (gas lines and tank in your trunk).

It's not a fuel catalyst and it does not help the fuel burn more completely. It's an additional fuel. Diesels only use enough fuel to provide power to maintain speed. When the propane is injected, you make additional power so you reduce the throttle position to keep from accelerating. This gives the illusion of increased MPG because the engine will be using some propane in the place of some diesel.

_____________________________

1980 240D 3.0VNTi 216K Miles. OM617.95, GT2256V VNT turbo, 4-speed manual, Intercooler, 3.46 diff, 15mm rear swaybar, ALDA removed, no EGR and Amsoil by-pass oil filter. Currently 107HP and 195lb/ft of torque at the wheels.

www.youtube.com/Turbo617

(in reply to drc1231)

Post #: 2

RE: propane injection - 5/6/2008 7:28:44 AM

jkrumpos

Posts: 4
Joined: 5/6/2008
Status: offline

I experienced some problems starting my '84 300 SD on the cold winter days in northern Wisconsin this past year, so I was looking for information on something called FlameStart that is apparently used on diesels in Scandanavia. The propane header caught my attention.

I understand that the injection of propane does not really reduce fuel consumption, but does it make the engine easier to start in very cold weather? Anyone have experience?

(in reply to ForcedInduction)

Post #: 3

RE: propane injection - 5/6/2008 1:47:17 PM

ForcedInduction

Posts: 672
Joined: 5/20/2006
From: Federal Heights, Colorado
Status: offline

Propane injection is mainly for the illusion of higher MPG and sometimes to get more power when they don't know how to turn up the injection pump for more fuel.

It is ignited by the injection and combustion of the Diesel fuel so, no, it won't help start the engine. It can actually damage the engine if used during startup because the glowplugs will ignite the fuel far too early.

You should look into a diesel fired Webasto heater. http://www.webasto.com/products/en/3115_3422.html
If you use the block heater you shouldn't need anything other than the glowplugs to start in sub-zero temperatures. I know that electrical access can sometimes be a problem, especially at work/school/apartments, so the webasto fills that gap quite well. The only downside is it can cost over $1000 by the time installation is included.

< Message edited by ForcedInduction -- 5/6/2008 1:51:09 PM >

_____________________________

1980 240D 3.0VNTi 216K Miles. OM617.95, GT2256V VNT turbo, 4-speed manual, Intercooler, 3.46 diff, 15mm rear swaybar, ALDA removed, no EGR and Amsoil by-pass oil filter. Currently 107HP and 195lb/ft of torque at the wheels.

www.youtube.com/Turbo617

(in reply to jkrumpos)

Post #: 4

RE: propane injection - 5/16/2008 7:30:58 AM

WD8CDH

Posts: 8
Joined: 6/20/2006
Status: offline

I have run several turbo and non-turbo engines with propane injection. In my experience, propane injection will slightly improve fuel economy. For example, running 9 gallons of diesel fuel and 1 gallon of propane got me a few more miles than running 10 gallons of diesel only, even though the diesel/propane mix has less total energy.

I believe that this is because the very lean charge air/fuel mixture improves the main combustion process a small amount. I found even fogging small amounts of DIESEL fuel in the intake gave slight improvements in both base specific fuel consumption and emissions. If the price of propane is substantually lower than diesel fuel, propane injection may be worth the trouble.

The benefit is a little more with a turbocharged engine than it is with a non-turbo.

(in reply to ForcedInduction)

Post #: 5