Converting a 240 to LPG..

[LankyTim]

Hi all,

I'm planning on converting my 245 to LPG soon. Its a late model with a lambder sond sensor and air mass meter. My question is will a spark still be produced when I turn the fuel pumps off (via the relay) or will I need some sort of "fuel pump emulator" to fool the ECU into thinking fuel is still being pumped through to the engine.

Also... where do I put the gas tank??

[classicswede]

Hi Tim,

if you are going to use a mixer system then the best way of doing it is by fitting a injector emulator (pitagora) to shut off the petrol injectors. If using a mixer you should fit closed loop electronics AEB leonardo KME bingo or similar.

Personaly I recomend to use a modern multi point system for best MPG and to save having engine management issues. Cost wise it is very little more than a mixer on a new install.

The tank fits in place of the spare wheel but is a special stand up type tank.

[LankyTim]

Thanks for the info!

I already have an old style mixer system lying about in my garage, plus a large doughnut tank which i'd like to use, if possible. It came from an injected 740 GLE. I was toying with the idea of having it lying flat on the boot floor, under the trap door. Obviously it would only conceal half the tank though!

What sort of engine management issues would I get if I just switched off the fuel pumps via the relay then?

[classicswede]

Lambda light, by going mixer. Petrol injectors failing do to running dry resulting in the car not running on petrol.

Injector emulators do come up on ebay every now and then.

[LankyTim]

Makes sense, I run a converted Audi 100 which has a carburetor so I don't know a huge amount of what's involved converting an injected engine.

The donor car had the earlier type injection system (K jet?) Would that have needed an injection emulator?

One final question for this post (promise!) I have found a few injector emulators on ebay, how do they work? Do I plug the existing injector leads into the emulator and the leads from the emulator into the injectors?

[classicswede]

Ebay item number 230550435048 should do the job for you. You simply plug them in between the petrol injector loom and petrol injectors. There is also a black earth wire and blue power wire. The blue power wire should be connected to blue gas solenoid live feed to shut them off when the car is on gas.

You also need a 65mm LPG mixer with a venturi to match your vapouriser.

[LankyTim]

Thanks for that, i'm getting to know LPG a bit better!

I think I have the correct mixer in a box somewhere...

[classicswede]

Originally Posted by LankyTim

I think I have the correct mixer in a box somewhere...

happy days