P38 heater & LPG failure

BOO-HOO!
My P38's heater on the drivers side has not worked for a while but its not bothered me too much but then the wife noticed it wasn't working on her side as well. Coupled with this the LPG had started to run very lumpy until it chokes the engine so much I have to revert back to petrol.
I know that part of the LPG system in the engine bay works off warmth from the heater system and upon inspection has been iced up, as well as the LPG filters and one of the two LPG distributors above the cylinder head.
Last year I changed most of the clips on the LPG hoses for jubilee types so I've checked these for tightness and they all seem fine.
I'm rather baffled and am fairly sure the LPG & heater problems are related but to be honest I'm not too clued up on the heating system on the car and am getting desperate but dont even know where to start looking in the engine bay!
Any help would be very much appreciated, any tips where to look & what to do will be warmly received and any **** takes will be taken in good faith!
Many thanks for taking the time to read this!

Just a stupid thought but have you checked your coolant level?

What's your temp guage reading?

the coolant level has been low lately, top it up regularly but no sign of head gasket damage and temp. reading bang in the middle as it should be.
im confused.com!

if the lpg is plumbed correctly the vapouriser is fed with hot water from the heater circuit,if the water level is correct in the header tank then you most likely hava a bockage or partial blockage in either the heater or vapouriser.

Ok. My thinking was that the lpg system needs warm water from the cooling system to evaporate the lpg. If it's freezing up that suggests it's not getting hot water - would also explain the cold heater.

When you say the coolant level was low, how low was it? You might have an airlock.

Would be worth feeling the hoses to the heater and evaporator when the engine is up to temp to see if they're warmm.

when you say the heater doesnt work do you mean the heat is not there or the blower doesnt work

Morning wonderful people!
The coolant level is usually minimum or lower, I'll top it up to the max ........then forget about it for a few days............then check and its usually back to the min or lower! (I dont deserve nice cars!)
Once the car has warmed up the temp needle is always bang on in the middle although lately the car has taken longer to start from cold but once warmed up if I have to switch off and restart it starts fine.
When I turn the fan dial I can hear the blower but no heat comes out.
Thanks for the advice so far, I'm off to have a look, any further help would be gratefully received!
Thanks again !

just 'topped up' the coolant with aprx 3.5 litres of water, took it for a blast down the A2 and it seems all is back to normal!
bit concerned it took in so much water, now need to work out where all the bl00dy water is goin!
also, read somewhere else about the heater display showing ' ! ' and then got stuck in a thread about the blower/heater/flap motors! OOOH, 'KIN ELL!!!

I had a leak on the top seal of the rad where the plastic attaches to the core couldnt see it as it was a weep and of course it was drying I also had a pin hole in the hose from the rad back to the expansion tank which was behind a bracket again took ages to find - the rads are crap and do fail frequently so check all hoses and connections before the dreaded heads and slipped liners if its a v8 good luck

sandyt said:

I had a leak on the top seal of the rad where the plastic attaches to the core couldnt see it as it was a weep and of course it was drying I also had a pin hole in the hose from the rad back to the expansion tank which was behind a bracket again took ages to find - the rads are crap and do fail frequently so check all hoses and connections before the dreaded heads and slipped liners if its a v8 good luck

Click to expand...

It is a V8, thanks for the advice, I'll have a look at the hoses etc but it was nice taking it for a quick blast today!
I'm now going to delve in the manual re the '!' and book symbol on the heater display!
its only been there on the display for a few months!
:doh:

i had exactly the same problem. Firstly if you have 2 vapourisers and youve seen them with ice around them then they will be fooched. the pipework for 2 vapourizers is far too long to cope with the flow needed for the heater. It needs a new vapouriser . A single double unit that can be connected next to the brake system. renew all pipes. I also suspect your head gaskets are leaking. Also check for coolant in the footwell drivers side . If youve had liquid lpg at the injectors you will need new o rings in the injectors (see my recent thread on replacing these)
This is what I've done to get my p38 up to pur like a kitten.
Head gaskets and all new associated gaskets and coolant pipes.
New rad
New vapouriser
new thermostat
new epansion tank
new o rings in heater matrix
new o rings in the injectors
new gas rubber pipes
new jubileee clips
Every coolant pipe replaced (easy when the heads are being done)
Also used irontite but only after all changed above.

To give you an idea if the heads have gone, take all plugs out and look for rust on ther plugs. If so bad luck new head gaskets and head bolts.
If you cannot do these jobs then there is no quick fix for this. Take my advise on the single vapouriser . £100 from tinely Tech near Cambridge. Fantactic compact unit that does the job great.
Some folk will think I've gone a little far. But a small leak in the cooling system not tended to will only end in disaaster and a lot of cash or a trip to the scrap yard for your car.

Got home from work tonight and once the car had cooled down I checked the coolant level........it took another 1.5 litres of water!
boo-hooo!

Willos said:

i had exactly the same problem. Firstly if you have 2 vapourisers and youve seen them with ice around them then they will be fooched. the pipework for 2 vapourizers is far too long to cope with the flow needed for the heater. It needs a new vapouriser . A single double unit that can be connected next to the brake system. renew all pipes. I also suspect your head gaskets are leaking. Also check for coolant in the footwell drivers side . If youve had liquid lpg at the injectors you will need new o rings in the injectors (see my recent thread on replacing these)
This is what I've done to get my p38 up to pur like a kitten.
Head gaskets and all new associated gaskets and coolant pipes.
New rad
New vapouriser
new thermostat
new epansion tank
new o rings in heater matrix
new o rings in the injectors
new gas rubber pipes
new jubileee clips
Every coolant pipe replaced (easy when the heads are being done)
Also used irontite but only after all changed above.

To give you an idea if the heads have gone, take all plugs out and look for rust on ther plugs. If so bad luck new head gaskets and head bolts.
If you cannot do these jobs then there is no quick fix for this. Take my advise on the single vapouriser . £100 from tinely Tech near Cambridge. Fantactic compact unit that does the job great.
Some folk will think I've gone a little far. But a small leak in the cooling system not tended to will only end in disaaster and a lot of cash or a trip to the scrap yard for your car.

Click to expand...

....and then I come here and thats cheered me right up! cheers willos!
all joking aside, thanks for the above, I'm going to have to just monitor the level till the weekend when I can spend some real time on it!.........
if it lasts that long! I certainly dont fancy commuting thru Blackcrawl tunnel in rush hour traffic in the SIIA without synchro!

Hi
Have you got any wet in the drivers side footwell ?

I've just sorted out my V8 with exactly the same symptoms. The steady loss of coolant means there is definitely a leak somewhere, and once there is not enough coolant to warm the lpg evaporators then the heater and the lpg will both not work. You need to find the problem fairly quickly because you're running the engine without enough coolant and you will blow a cylinder head gasket before much longer. If the engine is running smoothly then probably your CH gaskets are all right so far.
Top up the coolant and run it up to operating temperature, then leave it idling on lpg and check the following;
1. Check the carpet beneath the heater over the transmission tunnel. If it's wet it could be coolant, but it could also be water coming through the climate control filter covers. Check for drips, smell the wetness for coolant or rainwater. If it's coolant it is either the o-rings or the heater matrix.
2. Check the water pump at the front of the engine from underneath, is it wet/dribbling/dripping? The water pump is where I was losing coolant and it took a while to find.
3. Check carefully underneath the header tank and also the pipe leading from the header to the rad; this can split or wear a hole;
4. Check the rad carefully; look for wetness/drips anywhere. It can be tricky because there is a condenser radiator in front of the coolant one.
If you're losing 1.5 litres a day then you should be able to see where the water is coming from.
5. Check all hoses, especially connecting the evaporator to the heating system; I had an intermittent leak from one of those that took me months to find! Once I fixed that it made the water pump leak much worse!