LPG conversion- smoke?

[d780matt]

I have a 1986 t25 transporter coveted to run off LPG, but also runs off petrol
you have to switch off on the LPG then rev the engine to burn off the remaining petrol in the carb then as you feel the revs drop switch over to LPG.

Two questions, is this the normal set up and secondly in the ten second or so whilst the petrol burns off the exhaust gives of loads, and i mean loads, of white smoke is this normal, ive only had the van a few weeks, and only just got round to getting some LPG for it. Ive always had golf's before this so in my book white smoke is bad!

any thoughts ?

[Ian Hulley]

Two questions, is this the normal set up

Yes

and secondly in the ten second or so whilst the petrol burns off the exhaust gives of loads, and i mean loads, of white smoke is this normal,

No.

Do you know who the conversion was done by ? If so have a word with them. If not then I'd book it in with Steve at Gasure to have the system serviced and get his learned opinion.

Ian.

[dannybook]

Hi Mate,

Dont want to overly concern but It sounds like you are burning antifreeze.
Check your oil for discoloration. If it is a brownish color it could mean your oil and antifreeze are mixing.If the smoke continues whilst driving, Likely cause,head gasket gone.

If its just when you switch or start up on petrol, Could mean that the rubber valve stem seals have perished - especially as the vehicle is a few years old and if it has done alot of miles.

Either way I agree with the previous, get it looked at.

[toomanytoys]

Hi Mate,

Dont want to overly concern but It sounds like you are burning antifreeze.
Check your oil for discoloration. If it is a brownish color it could mean your oil and antifreeze are mixing.If the smoke continues whilst driving, Likely cause,head gasket gone.

If its just when you switch or start up on petrol, Could mean that the rubber valve stem seals have perished - especially as the vehicle is a few years old and if it has done alot of miles.

Either way I agree with the previous, get it looked at.

Sorry.. not strictly correct I am afraid..

The wbx (if thats whats fitted as no mention of engine code ) doesnt have valve stem seals or head gaskets that can leak oil into the cooling system.. If its a 2.1 then IF there is oil in the cooling system its most likely from the oil cooler..

As for the smoke.. you are sure it doesnt do it atany other time? as thats odd.. perhaps there is crud and water getting into the fuel system that is being used when the float bowl is emptied.. Check your fuel filter and all the breather and filler pipework on the fuel tank
also check the crankcase breather system isnt blocked/kinked
If a head is cracked, stud weak/broke or there is a head seal problem then it would do it at other times and the cooling system will pressurise and blow coolant out..

[dannybook]

Fair enough. I bow to your superior knowledge!!!

[Ian Hulley]

you have to switch off on the LPG then rev the engine to burn off the remaining petrol in the carb then as you feel the revs drop switch over to LPG.

OK, from the beginning for a 1.9 or 2.1 WBX running a carburettor ... Do you have the 3 position switch ... 'LPG' 'Off' 'Petrol' ?

When running on petrol to swap over to lpg ... click the switch from 'Petrol' to the center 'Off' position, this cuts off the fuel pump to the carb and the carb is now emptying itself of petrol. As the engine dies off switch straight over to 'LPG' and whooosh you're off.

When running on LPG to swap to petrol click straight across, prefferably NOT at traffic lights or on a roundabout because there can be a delay in picking up as the petrol is pumped through.

Ian

[chuckle-bus-tom]

The LPG-to-petrol or visa-versa switcheroos can often lead to some good laughs when recalling the situations caused!

Last weekend I ran out of LPG just as I was overtaking a lorry on the M25. Switching o petrol was not going to be quick as I hadn't needed to use it for a while and so I had to let the lorry pass under me (he was very confused/angry) so I could duck into the hard shoulder (doing 20mph by this point). Then, as a junction was coming up I rapidly started running out of hard shoulder.

It all came out in the wash and we passed the same lorry a minute later to more bemusement!

[Little Miss Pink]

[toomanytoys]

you have to switch off on the LPG then rev the engine to burn off the remaining petrol in the carb then as you feel the revs drop switch over to LPG.

OK, from the beginning for a 1.9 or 2.1 WBX running a carburettor ... Do you have the 3 position switch ... 'LPG' 'Off' 'Petrol' ?

When running on LPG to swap to petrol click straight across, prefferably NOT at traffic lights or on a roundabout because there can be a delay in picking up as the petrol is pumped through.

Ian

Depending on what system you have, most carb switch boxes allow you to switch to middle from gas and the carb fills up with fuel, as it does so a rich mix is caused and the power drops, switch it to the petrol position then.. this should only take 3 or 4 seconds at most..

As said always try and do this while traveling at a reasonable speed (40mph+) DO NOY dip the clutch etc.. just keep the throttle open at the same position...