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[Gaffers]

I hate to say it, hand the keys to a specialist and let them sort it. 

If the dealer is paying, why not? 

When it comes to LPG garages, the word specialist is used a little too liberally.  Even the LPGA qualified certifiers are pretty rubbish.

I can vouch for Kev, not just a gent but he really knows his onions with the LPG.  Just be sure to cross his hand with a few Hobgoblins

[Broomies Mate]

In terms of what I have;

Reducing Valve: Zavoli Zeta
Tank: Bormech 48Ltr
Control System: Stag 300 Premium
Injection Strip: Valtek

Looking at the service history, the main and vapour filters have been replaced every 2 years since install.

I know nothing about what I just typed! 

[PhilRich]

looking at the figures stag 300 come with different reducers.. one 140 hp(alaska)  and other 250 hp (magic jet) claimed..

There is no reason why the one particular set of injectors must be used with one particilar reducer. It is not a set of components all made together. Far from it in fact. Although a kit would have to include one or other obviously. There is a list of possible injectors in the software as long as your arm. From kahin as used on the Prins kits to the basic moto gas type or whatever....

These are chosen primarily from the Max bhp from the engine as said. The rest is down to budget. One might think that one lpg kit is much the same as another given the bhp, but things like lag and poor set up creep in the cheaper you go.

Achieving a decent idle and still keeping up at wot becomes harder with cheaper kits.

For instance the Kahin and Hanna injectors do ALL their work on duration to achieve correct fuelling. Where as the cheaper motogas ones rely on the use of nozzels to hold an amount of back pressure in the line. These have to be drilled to the correct diameter fir each particular engine.
 This can only be done by trial and error, although once done can be used on for all as on the 3.2 omegas here for example. They will all prety much run on a 1.2mm nozzel size iirc. As TB found out as his are too big, the idle and multipliers are quite differant to achieve a decent set over all.
 Obviously initial drilling of nozzels to find the right size means whipping the inlet out each time. None of this malarky is necessary with the Hanna and Kahin (prinz) injectors.

Please correct me if i'm wrong Chris but I thought the Inlet Manifold stubs were fitted 'full bore' as supplied &  the nozzles that need drilling to size are fitted directly to the Injectors? Also, the instructions with my Stag 400 kit gave 2.4mm as optimal injector orifice up to 150Bhp so your stated 1.2mm seems way too small

[TheBoy]

looking at the figures stag 300 come with different reducers.. one 140 hp(alaska)  and other 250 hp (magic jet) claimed..

There is no reason why the one particular set of injectors must be used with one particilar reducer. It is not a set of components all made together. Far from it in fact. Although a kit would have to include one or other obviously. There is a list of possible injectors in the software as long as your arm. From kahin as used on the Prins kits to the basic moto gas type or whatever....

These are chosen primarily from the Max bhp from the engine as said. The rest is down to budget. One might think that one lpg kit is much the same as another given the bhp, but things like lag and poor set up creep in the cheaper you go.

Achieving a decent idle and still keeping up at wot becomes harder with cheaper kits.

For instance the Kahin and Hanna injectors do ALL their work on duration to achieve correct fuelling. Where as the cheaper motogas ones rely on the use of nozzels to hold an amount of back pressure in the line. These have to be drilled to the correct diameter fir each particular engine.
 This can only be done by trial and error, although once done can be used on for all as on the 3.2 omegas here for example. They will all prety much run on a 1.2mm nozzel size iirc. As TB found out as his are too big, the idle and multipliers are quite differant to achieve a decent set over all.
 Obviously initial drilling of nozzels to find the right size means whipping the inlet out each time. None of this malarky is necessary with the Hanna and Kahin (prinz) injectors.

Please correct me if i'm wrong Chris but I thought the Inlet Manifold stubs were fitted 'full bore' as supplied &  the nozzles that need drilling to size are fitted directly to the Injectors? Also, the instructions with my Stag 400 kit gave 2.4mm as optimal injector orifice up to 150Bhp so your stated 1.2mm seems way too small

You are correct

[chrisgixer]

....or was as it 2.1mm? And the Hannas need differant bore pipes than the valtecs? Meaning the manifold needs to come out....

I did say iirc. ....iirc

[TheBoy]

I did say iirc. ....iirc

Clearly you didn't (remember correctly)

[chrisgixer]

I did say iirc. ....iirc

Clearly you didn't (remember correctly)

...what day is it? Not Friday that much I'm sure of.

[TheBoy]

I did say iirc. ....iirc

Clearly you didn't (remember correctly)

...what day is it? Not Friday that much I'm sure of.

Its most definitely Sunday. *sigh*, back to dealing with idiots tomorrow.

[Kevin Wood]

A couple of points:

The exhaust goes through a cat, which will burn off any excess gas. I've never smelt gas through the exhaust of an LPG car. I think with the engine at full chat you'd leave it behind pretty quick too.

On a turbo car the LPG pressure follows the boost pressure, so the pipework is subject to much more pressure when the engine is on boost. So, if it's going to leak, that's when it'll be.

[Broomies Mate]

A couple of points:

The exhaust goes through a cat, which will burn off any excess gas. I've never smelt gas through the exhaust of an LPG car. I think with the engine at full chat you'd leave it behind pretty quick too.

On a turbo car the LPG pressure follows the boost pressure, so the pipework is subject to much more pressure when the engine is on boost. So, if it's going to leak, that's when it'll be.

Thanks Kevin.  All pointers are greatly appreciated. 

The car goes like a scolded cat, so I'm quite sure there are no boost leaks.  The Gauge (albeit not a true boost gauge) hits the red, which is where it should be (until the re-map, anyway).

There is definitely a smell of LPG when running on LPG.  Alton is a fair old distance from Bristol, and whilst I would much, much prefer your expertise and (probably) lower cost diagnostics, I feel I have no other choice than to take it to the company who have been looking after the car for the last 8 years. 

[Andy H]

A couple of points:

The exhaust goes through a cat, which will burn off any excess gas. I've never smelt gas through the exhaust of an LPG car. I think with the engine at full chat you'd leave it behind pretty quick too. I was thinking of the smell I get when my central heating boiler is running and the wind blows the flue gas down to face level - not sure if the cat would change the nature of those gases

On a turbo car the LPG pressure follows the boost pressure, so the pipework is subject to much more pressure when the engine is on boost. So, if it's going to leak, that's when it'll be. That makes sense - leak testing may be difficult if the pipes only leak at full boost though. Might be necessary to find another way to pressurise the gas pipes?

[cem_devecioglu]

In terms of what I have;

Reducing Valve: Zavoli Zeta
Tank: Bormech 48Ltr
Control System: Stag 300 Premium
Injection Strip: Valtek

Looking at the service history, the main and vapour filters have been replaced every 2 years since install.

I know nothing about what I just typed! 

http://www.zavoli.com/en/product/40-riduttori-zeta?lang=en

[Broomies Mate]

In terms of what I have;

Reducing Valve: Zavoli Zeta
Tank: Bormech 48Ltr
Control System: Stag 300 Premium
Injection Strip: Valtek

Looking at the service history, the main and vapour filters have been replaced every 2 years since install.

I know nothing about what I just typed! 

http://www.zavoli.com/en/product/40-riduttori-zeta?lang=en

Thanks Cem.  So we can safely say the Reducer is fit for 340BHP (1.4Bar).  Even after the planned re-map, I'm looking at 280BHP / 350Nm.  There must be a leak somewhere or the ECU has lost configuration for some reason?

[D]

The older one was a Zeta S, the newer one is called Zeta N. I think the older S was rated for around 200bhp. What exactly have you got? I suspect it is a S and hence not capable of supplying the demands of your engine.

Re: the leak. Check the multivalve with some soapy liquid. Most common site of leak that lets you smell gas within the cabin.

[TheBoy]

In my experience, tiny leaks produce a lot of smell. These sort of leaks would barely impact running (on a non turbo car, not sure what sort of gas pressures a turbo would need).

In my experience, this does sound like insuffucient (gas) fuelling at high RPM, which would point to underrated components, esp the evapourator/vapouriser/reducer or whatever else you want to call it, injectors or nozzle size.  Its possible the pressure from evap has dropped (split diaphram?).

Get the lead on in whne it arrives, and see whats what. If it is underrated components, you have the option to get it to switch back to petrol at high RPM - you'll see in the software

I doubt the ECU has lost all its settings, as its unlikely the thing would run.