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[tigers_gonads]

I've got a little LPG leak on my car but here is the funny thing, you only smell it in the cabin when the lpg tank is nearly empty 
It never smells when full of even half full 

Any ideas ?

[zirk]

Strange, end of the day a leak is a leak so will need sorting, could it be coming through the heater vents from the engine bay?

If it helps, when they do leak you tend to get a white frosted deposit build up from around the culprit / area, but that will soon disappear (melt) when the leak stops

[Entwood]

Had similar a few years back which quickly got worse followed by the engine refusing to run on LPG... so it went to a local specialist PDQ ...

In my case the internal pickup pipe had corroded such that when the level dropped to less than 1/3rd the pickup was collecting gas not liquid, seems this affects the way the vaporiser/injectors cope and leads to a smell of unburnt LPG in the engine compartment which drifts into the cabin, followed by a drop in pressure such that it won't run on LPG. Stand for 10 minutes the pressure builds back up and it runs for 5 minutes before the cycle repeats.

Solution is either have enough LPG in the tank to cover the hole, or, as I did, fit a new tank !!.

Apparently the pickup pipe is thin stainless steel, all it needs is a scratch during manufacture to allow corrosion to set in as it is stainless NOT "corrode-less" and steel corrodes quickly in contact with LPG.

Probably all wrong but that is what I was told, new tank did however sort the problem out    Might not be your problem .. but worth mentioning ..

[TheBoy]

Had similar a few years back which quickly got worse followed by the engine refusing to run on LPG... so it went to a local specialist PDQ ...

In my case the internal pickup pipe had corroded such that when the level dropped to less than 1/3rd the pickup was collecting gas not liquid, seems this affects the way the vaporiser/injectors cope and leads to a smell of unburnt LPG in the engine compartment which drifts into the cabin, followed by a drop in pressure such that it won't run on LPG. Stand for 10 minutes the pressure builds back up and it runs for 5 minutes before the cycle repeats.

Solution is either have enough LPG in the tank to cover the hole, or, as I did, fit a new tank !!.

Apparently the pickup pipe is thin stainless steel, all it needs is a scratch during manufacture to allow corrosion to set in as it is stainless NOT "corrode-less" and steel corrodes quickly in contact with LPG.

Probably all wrong but that is what I was told, new tank did however sort the problem out    Might not be your problem .. but worth mentioning ..

Surely it needed new valve set, not tank?

[Entwood]

Had similar a few years back which quickly got worse followed by the engine refusing to run on LPG... so it went to a local specialist PDQ ...

In my case the internal pickup pipe had corroded such that when the level dropped to less than 1/3rd the pickup was collecting gas not liquid, seems this affects the way the vaporiser/injectors cope and leads to a smell of unburnt LPG in the engine compartment which drifts into the cabin, followed by a drop in pressure such that it won't run on LPG. Stand for 10 minutes the pressure builds back up and it runs for 5 minutes before the cycle repeats.

Solution is either have enough LPG in the tank to cover the hole, or, as I did, fit a new tank !!.

Apparently the pickup pipe is thin stainless steel, all it needs is a scratch during manufacture to allow corrosion to set in as it is stainless NOT "corrode-less" and steel corrodes quickly in contact with LPG.

Probably all wrong but that is what I was told, new tank did however sort the problem out    Might not be your problem .. but worth mentioning ..

Surely it needed new valve set, not tank?

According to LPG place the internal pickup pipe is not replaceable, and given the amount of red metallic crud that came out of the filter I went along !!

They "might" have done me .. but the tank was 6 years into its 10 year life anyway .. so a new tank wasn't that bad an idea IMHO ....saves worrying about changing the tank later anyway ..

[Lazydocker]

Had similar a few years back which quickly got worse followed by the engine refusing to run on LPG... so it went to a local specialist PDQ ...

In my case the internal pickup pipe had corroded such that when the level dropped to less than 1/3rd the pickup was collecting gas not liquid, seems this affects the way the vaporiser/injectors cope and leads to a smell of unburnt LPG in the engine compartment which drifts into the cabin, followed by a drop in pressure such that it won't run on LPG. Stand for 10 minutes the pressure builds back up and it runs for 5 minutes before the cycle repeats.

Solution is either have enough LPG in the tank to cover the hole, or, as I did, fit a new tank !!.

Apparently the pickup pipe is thin stainless steel, all it needs is a scratch during manufacture to allow corrosion to set in as it is stainless NOT "corrode-less" and steel corrodes quickly in contact with LPG.

Probably all wrong but that is what I was told, new tank did however sort the problem out    Might not be your problem .. but worth mentioning ..

Surely it needed new valve set, not tank?

According to LPG place the internal pickup pipe is not replaceable, and given the amount of red metallic crud that came out of the filter I went along !!

They "might" have done me .. but the tank was 6 years into its 10 year life anyway .. so a new tank wasn't that bad an idea IMHO ....saves worrying about changing the tank later anyway ..

IIRC the 4 hole tank has the pickup fixed during manufacture

[tigers_gonads]

That lot rings a few bells Nige sadly but one thing that I can't quite get my head around 

The LPG setup has 2 12volt solenoid valves on the system.
1 on the tank and one on the KME Gold reducer.
Plus the 6 injectors which also should be closed.

With no volts at either solenoid, my understanding is that these 2 should isolate the LPG at both the tank end and the reducer end.
Is it a case that they will stop lpg liquid under nominal pressure but not gas vapour ?

I have noticed that if I park my car up with say 1 green light on the controller for a few days then go back to it, you can bet your life whether I can smell gas or not that the red light will be on when the engine is started 
Also I know these systems tend to hunt around a little when its dragging the last few miles worth upto the engine but in the last 6 months or so, its been much worse 

Might not be connected but about 4 years ago, with a full tank of lpg and on a very hot day, the pressure relief valve blew causing one of the loudest bangs i've ever heard.
Could this be connected ?
Also when the kit was fitted to my old pfl, one of the injector wires did get welded to the exhaust manifold after a cable escaped the loom after some maintenance work.
It has caused injector faults in the past due to possibly straining the injector solenoid open but I haven't had this problem for a few years 

For reference, the system has been on 2 cars of mine and is getting on for 6 years old 

[Stargazer57N]

I would say is to get the leak fixed for your own safety as LPG is highly flammable.

[tigers_gonads]

I would say is to get the leak fixed for your own safety as LPG is highly flammable.

That's certainly the cunning plan 

[Entwood]

That lot rings a few bells Nige sadly but one thing that I can't quite get my head around 

The LPG setup has 2 12volt solenoid valves on the system.
1 on the tank and one on the KME Gold reducer.
Plus the 6 injectors which also should be closed.

With no volts at either solenoid, my understanding is that these 2 should isolate the LPG at both the tank end and the reducer end.
Is it a case that they will stop lpg liquid under nominal pressure but not gas vapour ?

I have noticed that if I park my car up with say 1 green light on the controller for a few days then go back to it, you can bet your life whether I can smell gas or not that the red light will be on when the engine is started 
Also I know these systems tend to hunt around a little when its dragging the last few miles worth upto the engine but in the last 6 months or so, its been much worse 

Might not be connected but about 4 years ago, with a full tank of lpg and on a very hot day, the pressure relief valve blew causing one of the loudest bangs i've ever heard.
Could this be connected ?
Also when the kit was fitted to my old pfl, one of the injector wires did get welded to the exhaust manifold after a cable escaped the loom after some maintenance work.
It has caused injector faults in the past due to possibly straining the injector solenoid open but I haven't had this problem for a few years 

For reference, the system has been on 2 cars of mine and is getting on for 6 years old 

Doesn't sound quite like my problem then .. I never actually had "leak" as regards a "known" loss of LPG, just that when low AND RUNNING there was a slight whiff of LPG, when not running there was never any smell, that was half my problem .. I kept looking for a leak that wasn't there !!

It was when the whiff got a bit stronger and the engine started dropping back to petrol that I took it to the LPG place for advice, they were very quick to suspect this pickup pipe - known problem ?? - and went for the filter as a backup .. I watched them take it off and pour - literally - metallic red crap out of the filter onto a piece of paper !! They also said that if it hadn't of been for a decent filter I'd be buying a new vapouriser as well ..

[tigers_gonads]

Okay Nige, thanks anyway 
Does sound like you had a luck escape with the red shit in the tank though 
 
I cant get my head around how / why i've got a leak when the tank is pretty empty but not when full 
I'd have thought that a full tank would mean more static pressure giving me more of a chance of a leak 

This is bugging me now 

[Doctor Gollum]

Vapour would leak more readily than liquid as the molecules are far smaller

[TheBoy]

Had similar a few years back which quickly got worse followed by the engine refusing to run on LPG... so it went to a local specialist PDQ ...

In my case the internal pickup pipe had corroded such that when the level dropped to less than 1/3rd the pickup was collecting gas not liquid, seems this affects the way the vaporiser/injectors cope and leads to a smell of unburnt LPG in the engine compartment which drifts into the cabin, followed by a drop in pressure such that it won't run on LPG. Stand for 10 minutes the pressure builds back up and it runs for 5 minutes before the cycle repeats.

Solution is either have enough LPG in the tank to cover the hole, or, as I did, fit a new tank !!.

Apparently the pickup pipe is thin stainless steel, all it needs is a scratch during manufacture to allow corrosion to set in as it is stainless NOT "corrode-less" and steel corrodes quickly in contact with LPG.

Probably all wrong but that is what I was told, new tank did however sort the problem out    Might not be your problem .. but worth mentioning ..

Surely it needed new valve set, not tank?

According to LPG place the internal pickup pipe is not replaceable, and given the amount of red metallic crud that came out of the filter I went along !!

They "might" have done me .. but the tank was 6 years into its 10 year life anyway .. so a new tank wasn't that bad an idea IMHO ....saves worrying about changing the tank later anyway ..

IIRC the 4 hole tank has the pickup fixed during manufacture

Only time I've seen a 4 hole tank with all the valves out was TBE, and I vaguely recall it was just a tank with 4 holes in.  All pickups, floats etc were part of the valve set.  Same as single hole tank....

[Lazydocker]

Had similar a few years back which quickly got worse followed by the engine refusing to run on LPG... so it went to a local specialist PDQ ...

In my case the internal pickup pipe had corroded such that when the level dropped to less than 1/3rd the pickup was collecting gas not liquid, seems this affects the way the vaporiser/injectors cope and leads to a smell of unburnt LPG in the engine compartment which drifts into the cabin, followed by a drop in pressure such that it won't run on LPG. Stand for 10 minutes the pressure builds back up and it runs for 5 minutes before the cycle repeats.

Solution is either have enough LPG in the tank to cover the hole, or, as I did, fit a new tank !!.

Apparently the pickup pipe is thin stainless steel, all it needs is a scratch during manufacture to allow corrosion to set in as it is stainless NOT "corrode-less" and steel corrodes quickly in contact with LPG.

Probably all wrong but that is what I was told, new tank did however sort the problem out    Might not be your problem .. but worth mentioning ..

Surely it needed new valve set, not tank?

According to LPG place the internal pickup pipe is not replaceable, and given the amount of red metallic crud that came out of the filter I went along !!

They "might" have done me .. but the tank was 6 years into its 10 year life anyway .. so a new tank wasn't that bad an idea IMHO ....saves worrying about changing the tank later anyway ..

IIRC the 4 hole tank has the pickup fixed during manufacture

Only time I've seen a 4 hole tank with all the valves out was TBE, and I vaguely recall it was just a tank with 4 holes in.  All pickups, floats etc were part of the valve set.  Same as single hole tank....

As I fitted the valve set I'm sure the only one that had to be "fed" in was the float arm

[Kevin Wood]

Yep, pickup pipe is built into a 4 hole tank and the valve just bolts up to the threaded bush in the tank.