engine runs on lpg only not on gasoline

Post by **Pablo** » 05 Jun 2006 05:51 am

My 340 DL won't run on gasoline anymore, just on LPG. The technicians in the shop say that they are not able to fix the problem. They've installed a new fuelpump, filter and replaced most of the fuelhoses in the engine compartment, but it just won't run on regular fuel.

Any ideas????

Post by **redline** » 05 Jun 2006 08:11 am

one for Dai (classicswede ) methinks p.m. him pablo
or there is another lpg man on the forum , I think its green van man

Website · Post by **antiekeradio** » 05 Jun 2006 08:46 am

sounds like a clogged-up carburettor...

Post by **Pablo** » 05 Jun 2006 09:28 pm

If the carb is clogged, how can I fix it???? New nozzles?

Website · Post by **antiekeradio** » 05 Jun 2006 10:13 pm

recommended: complete dismantling and thorough cleaning, new rubber seals and diafragms (if needed). check/adjust float hight and choke levers.

alternative: replacement from scrapyard.

Post by **classicswede** » 15 Jun 2006 09:15 pm

Has it only happend after the conversion? or has it been ok for a long time then suddenly developed?
If it happened just after conversion I would say the lpg mixer is restricting the air flow making it run too rich.

Also try putting your LPG switch to the middle position - this should make it run on both fuels - the engine should start running lumpy then maybe even stall. If that does not happen then your are not getting any fuel out of the carb.

Hope this makes sense.

Post by **Pablo** » 18 Jun 2006 10:05 pm

I found that the carb was not closed. Apparently somebody had tried to fix it by taking it apart and putting it back together in the wrong order. The centre fuel nozzle (vertical little pipe) was mounted upside down. There was an addtitional washer installed that made it impossible to seal off the carb with the five screws on top. There was a 3 mm gap between the housing and the top. The seal between these 2 parts is completely dried out and the fuel bowl is full of dirt and dust.

Following back the fuel line I hit a sort of switch/solenoid that closes the fuel when switching between lpg and fuel. A clicking sound should be heard when swiching, but I hear nothing. I'll check this out later.

Going further I hit the fuelpump that is dried out as well. It is actually leaking a lot of oil. Initially I thought it was the mounting to the engine block, but it turnd out to be the seal between the housing of the pump and the top. I had no idea there is oil going into this pump at all. It makes a big mess.

So now I have a challenge. Apparently the dealer is not able to order the seals for the carb or the fuel pump. I have to options: started cutting seals myself or using this lock tight seal stuff. Unless anybody knows how to get the original seals

Post by **pettaw** » 19 Jun 2006 02:10 am

I would get a carb from a scrappy and swap over the bits you need, although gaskets should be available from a carb dealer. I would do the same for the fuel pump.

Post by **classicswede** » 20 Jun 2006 06:47 pm

The solenoid in the petrol pipe line should click when you switch to petrol mode. If it is not clicking you can over ride it by moving the lever or be screwing the screw at the bottom depending on which type it is.

Post by **Pablo** » 29 Jun 2006 10:37 am

Since it all was either wrongly fixed or faulty I decide to start at the beginning. I took the fueltank from the car and inspected the remaining fuel and the "fuel intake" (don't know the english word). The fuel itself was green brown collored and had hardly any odor. Somebody explained that it is probably rubberized due to its age. Then I looked at the fuel intake, the little rubber hose was totally collapsed. There would be no possibilty to suck any fuel out of this tank. When I tried to remove this little hose it totally desintegrated. So I replaced this line and flushed the fueltank with clean fuel. During the removal of the fuel tank one of the bolts snapped. It took about 1,5 hours to drill a hole and make it suitable for a new bolt. I'm not a mechanic, so this took a while. Luckily I had help from experienced mechanics, but it still takes a long time. Because of this I was not able to check the remaining fuellines forward. I'll do that next time.

I removed the fuelpump from the engineblock and made a temporary fix by installing a little metal plate (homemade with same size and dimensions as the pump) to seal of the engine. Finally no more oil leaking.....

to be continued