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[Entwood]

As many know, my 3.2 has a BRC Sequent LPG system fitted, which is 5 yeasr ols and HAD been as good as gold, until a few days ago.

Symptoms were (initially) it would run fine from overnight, switching to LPG after about 1 mile and continuing to run.... but if then switched off and restarted after about 30 minutes, it would start on petrol (as it is designed to do) then switch to LPG after about 5 seconds, only to just die ... The EML light would come on saying that all petrol injectors had lost power - which is sensible as the LPG ECU has switched them off ! Leave it for an hour or so and it seemed to work OK.

I then had a few days of absolutely no problems at all, then it all started again ... and I realised, and have no proved, that with more than 1/2 a tank of LPG it works perfectly, with less then 1/2 it plays up, with less than 1/4 it simply won't run on LPG at all 

Took it into a local LPG place, which has only recently become a BRC place. they have confirmed the fault (with 1/4 tank) as no liquid LPG in the feed line from the tank to the vapouriser. They also found large amounts of corroded particles, looks just like a large spoonful of black talcum powder, in the liquid feed filter and the vapouriser pressure switch

Their "best guess" is that the liquid feed pickup in the tank has corroded and when below 1/2 - 1/4 tank the "hole" is in the vapour area of the tank, so no liquid LPG gets to the vapouriser. If the tank is full the hole is immersed in LPG and the system works as designed.

The "logic" of this makes sense to me, but I have no knowledge to prove/disprove the line of reasoning. I ask the LPG experts for their views please.

To rectify the problem they propose to fit a new tank as that will have a new pickup, new tank valves, and a new pressure switch at the vapouriser.

Including labour and VAT they reckon on £630.00 (80 litre tank).

They say they have to fit new tank valves as they cannot remove/reuse the existing valves as there is 15 litres LPG in the tank, and removing the valves would dangerously vent the tank, which they have no facilities to empty. On order to avoid some serious charges for disposal, I will be taking the tank away (with the 15 litres in it) and venting it in a field somewhere !! then removing the valves and taking it to a scrappy.

Does any of that sound plausible ... or am I being taken to the cleaners ??

[tunnie]

What is the feed pipe made of? 

Just dug through all my LPG photos, only found one showing the liquid feed pickup, while still in it's box...



So mine looks like Copper?

Just googled 'Copper and LPG corrosion', the feed pipes here (we used Polyflex of course, assume yours does?)

http://www.foma.it/english/rame/rotoli-ricotti-rivestiti-gpl.html

Suggests a grade of copper to preserve against corrosion 

[Marks DTM Calib]

I would of thought tank replacement would be very diyable 

[tunnie]

I would of thought tank replacement would be very diyable 

If I could fit an LPG tank, it's very DIYable 

[Kevin Wood]

IIRC, it's a 4 hole tank?

I believe the pickup is a pipe that's actually built into the tank on those, which leads up from the bottom of the tank to behind the tank valve boss on the connection plate.

I really struggle to see what's to go wrong there, to be honest. I wonder if the real answer is that you've picked up a load of crud in a fill of fuel and it's been gradually blocking the system?

The sensitivity to level is strange, though. That does point to a leak into the pickup pipe. Either way, it's a straightforward DIY job to replace the tank if it does come to that, for half that price too.

Will it run at all on the remnants of the tank of you force it to switch over?

I find it hard to believe that it wouldn't, tbh. A car drawing vapour will baulk after a few minutes of motorway cruising, but for it not to switch over at all seems odd. Maybe the crud has caused a partial blockage somewhere.

If you can get it to run even gently and in short bursts from the vapour that's emptying the tank sorted (although, in reality, it's not too bad. Once the initial pressure has been relieved it just boils off gently).

[tunnie]

Another random thought, what about releasing the straps, allowing you to rotate the tank? If the pipe work allows, rotate it 180 degree's if you can, leave it over night see if the 'silt/crap' moves? Changes the behaviour?

[Entwood]

I would of thought tank replacement would be very diyable 

It would be ... if I had no time constraints, but due to Mrs E's condition she cannot travel in the clit for another few weeks at least, and won't be allowed to drive it for at least 6 weeks !! Therefore the only means of transport we have, for her, is the Omega...

so I have had 2 options:
1) get it sorted by the garage for £630, it will pay for itself in 7 months,
2) Run on petrol until Mrs E is well enough to take it off the road while I do the job.

I know Mrs E has no intention of going anywhere by any car at the moment, but my thoughts are very much on the "what if" scenario should I need to get her back into hospital.

EDIT

After discussions at home we have gone for option 1, the garage will do the work next Monday.... takes all the pressure/worries off .. job will be done

[tunnie]

Could you not get it up here, maybe KW's or TB's? Surely we could fairly easily pop the tank out and inspect the insides?

That's an awful lot of money for a tank change, thats about what I paid for my entire kit, putting LD up in a hotel, buying curry for all and beer and bacon wraps! 

[05omegav6]

Would have thought about £300 including tank/fittings/poly pipe to the vapouriser and a sunny afternoon would see it sorted

[Kevin Wood]

Agreed. That's rather expensive, and it's not as if the car will actually be off the road for significant time. I reckon, if you forget diagnosis and bite the bullet on a tank swap, a swap like-with-like would take an hour or two, with the car able to be made mobile again at all times, TBH. 

[Entwood]

Thanks Kevin, Al and Tunnie for the very intelligent thoughts ... 

Feed pipe on this tank is a fixture and not removable I'm told, and is stainless steel not copper. The corrosion particles are, according to the garage, what you get if stainless steel has a fault and LPG "attacks" it .. LPG being highly corrosive, so they say.

Now its down to less than 1/2 a tank it will not run on LPG at all, lasts about 15 seconds at idle, dies instantly if switched at more than 2000 rpm

I'm told - have no proof - that the feed pipe does not go all the way to the bottom so as NOT to pick up any crap/heavy ends that get into the tank, so not sure the rotation idea would assist ..

As just edited my previous - which I thought I had posted but was still sitting waiting that final action - Mrs E and I have chatted about it and made, possibly the wrong, decision, purely for peace of mind given the present circumstances.

[05omegav6]

As you say, it will pay for itself soon enough, and at least you have a definite timeframe for it be sorted...

[tunnie]

I'm told - have no proof - that the feed pipe does not go all the way to the bottom so as NOT to pick up any crap/heavy ends that get into the tank, so not sure the rotation idea would assist ..

As just edited my previous - which I thought I had posted but was still sitting waiting that final action - Mrs E and I have chatted about it and made, possibly the wrong, decision, purely for peace of mind given the present circumstances.

Of course you have to do what suits your needs, of course it will pay back, just a shame it's at that cost and time.

My thoughts on rotation, were that as you describe it, suggests crud is in the pipe leading up the tank. Moving it, may shift what ever it is. Perhaps just alter what it is doing currently, that my backup the silt/crap theory, if not, then maybe the feed pipe does have a hole 

Stainless steel having a fault eh? Hummm can't help but feel there is some garage BS in that 

[Marks DTM Calib]

Depends on the grade of stainless.

In fact in Marine, we rarely use stainless as its terrible with salt water and any grade that is any good is bloody brittle.

[Yasmine Lee]

in some case it is possible to remove the pick up pipe and can actually find that the tank will freeze up keeping it cool enough the keep some of the lpg gas in liquid form. as long as you have a new spare to put back in st8 away.

have seen it done btw