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Chat Area => General Car Chat => Topic started by: JamesV6CDX on 19 December 2011, 23:02:40

Title: 3.2 MV6 - My DIY LPG Conversion
Post by: JamesV6CDX on 19 December 2011, 23:02:40
Just thought I'd post up some information and a few pictures from my DIY LPG conversion, which I did in July this year.

Apart from some help welding/mounting the tank frame, which was kindly given by Mr Sassanach, I did this conversion on my driveway, and it is the first time I've converted a V6 from start to finish on my own. I'm sure there are areas for improvement, but it's a safe, functional, and reasonably tidy conversion, and easily matches a lot of 'LPGA professional' installations I've seen.

In terms of cost, the tank and filler were new, as was all the pipework throughout. I also bought a new Vaporisor - KME Gold dual output, which is recommended on here - and used 8mm Poly for the liquid feed.  The injectors (Valtek 3ohms), ECU, and loom were second hand Stag 300 items (although the injectors were almost new).

So essentially, a new conversion, just the loom and ECU were used, and these don't really "wear".

All in all - cost was in the region of £470, all in. This was six months ago, and whilst I've not really kept records, I daresay the conversion has easily paid for itself by now.

The only pics I have yet to upload (and I will update this thread once they arrive in my emails from my camera phone!) are the reducer.

I mounted this, by ditching the aux coolant pump, and using the bracket for the vaporisor. Simples! The Vaporisor is fed in the correct way - from the coolant bridge, around the circuit, and back to HBV, so it has a consistent flow of hot coolant.

On to the conversion -

Here is the tank, located in the boot. This is a 90 litre tank, which fills to around 72 litres in reality, given the expansion buffer. (Note, this picture doesn't show the extra vent hose - which comes out of the left of the gas tight box on the tank.

(http://i89.photobucket.com/albums/k205/jamesv6cdx/1_640x480.jpg)


This is the filler, located in the drivers side rear quarter panel. If you don't have a towbar, and don't want to have a "number plate filler" - this is the best option, In my view. Especially when you are priviliged enough to have use of "the cutter" from Mr sassanach, which makes the hole like a hole knife in butter ;D - note, this was properly rust proofed before fitment. This is essential, if you don't want bubbles of rust around it in a few years.

(http://i89.photobucket.com/albums/k205/jamesv6cdx/2_640x480.jpg)

With regards to mounting the nozzles in the inlet manifold - these need to be as close to the petrol injectors as possible,  for best results on LPG. I very nearly chickened out and asked Mr Kev Wood to drill and tap my manifold, but,  no balls no glory, I decided to have a go myself.

Here is one of the holes, drilled out to 5mm, (with a cordless handheld drill ;D ) ready to be threaded. As you can see,  it comes out very close to the petrol injector hole - and - there is no room to get this wrong!!

(http://i89.photobucket.com/albums/k205/jamesv6cdx/4_640x480.jpg)

As has been mentioned before, lots of swarf is generated from this process, and is why you should NEVER let an 'installer' drill a manifold, without removing it!!

(http://i89.photobucket.com/albums/k205/jamesv6cdx/6_640x480.jpg)


Here is the hole, being threaded to a M6 thread, ready for the nozzle. Don't laugh, I couldn't find the correct tool to drive the tap - but a pair of mole grips seemed happy enough! Plenty of grease on the tap, and frequent backward turns, carefully making the new thread:

(http://i89.photobucket.com/albums/k205/jamesv6cdx/5_640x480.jpg)
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: JamesV6CDX on 19 December 2011, 23:03:06
Mounting the nozzles, in the newly created holes. These need a good coat of thread lock:


(http://i89.photobucket.com/albums/k205/jamesv6cdx/7_640x480.jpg)


And, the finished manifold. Here you'll see the gas nozzles, next to the petrol injectors:


(http://i89.photobucket.com/albums/k205/jamesv6cdx/8_640x480.jpg)


Now, I never was brilliant with Metalwork, but, set to work making a couple of brackets to hold the LPG injectors in a suitable place, for each bank.

For the 1-3-5 bank, I managed to make quite a neat bracket, that bolts on using the two bolts holding the fuel pipes to the manifold. This side looks quite good if I say so myself. The 2-4-6 bank, whilst not quite so elegant, still looks and works fine. For this side, I made a supporting strip of steel to go between the two cable tray bolts on the passenger side of the plenum, and a couple of L shaped brackets to support the injectors.

In the case of either side, I used the rubber vibration dampeners.

So here are the injectors, offered up, and mounted where they will go:

(http://i89.photobucket.com/albums/k205/jamesv6cdx/3_640x480.jpg)

In this picture, you can see the injectors fully connected up, to both the LPG loom, and connected to the stubs in the inlet manifold, and with their respective vapour feeds connected from the KME.

Not too crowded, and still pretty neat really.

1-3-5 bank:

(http://i89.photobucket.com/albums/k205/jamesv6cdx/10_640x480.jpg)

2-4-6 bank:

(http://i89.photobucket.com/albums/k205/jamesv6cdx/11_640x480.jpg)

Here you can see the LPG vaccum pipe, going from the plenum, to the Vaporisor, via the T peice up to the measurement Tee

(http://i89.photobucket.com/albums/k205/jamesv6cdx/9_640x480.jpg)

You will note this is coated with a protective sheath. This is because I thought that, upon entry to the vap, it may be a little close to a coolant pipe.

And - the finished product. This shows the gas filters, route of vapour hose / loom, etc.

(http://i89.photobucket.com/albums/k205/jamesv6cdx/12_640x480.jpg)


For a first time DIY V6 - I'm perfectly happy with this! The switchover from petrol to gas is quick, un-noticable, and performance identical on either fuel. No flat spots, no fuss at all, just great performance and reliability.

70p a litre - thank you very much!!
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: serek on 19 December 2011, 23:13:52
look good :y how long take to get all fit?? what sort of lpg system you use??
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: JamesV6CDX on 19 December 2011, 23:19:53
look good :y how long take to get all fit?? what sort of lpg system you use??

A few hours each evening, for a week, in the summer. It's a stag 300, with Valtek injectors (3 ohm) and a KME Gold reducer :)
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: feeutfo on 19 December 2011, 23:32:42
Manifold nozzle hole a bit close to the gasket line perhaps. I'd bring that inboard a fraction on the next one James, tbh. ;)
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: JamesV6CDX on 19 December 2011, 23:37:20
Manifold nozzle hole a bit close to the gasket line perhaps. I'd bring that inboard a fraction on the next one James, tbh. ;)

Agreed... like I say, a couiple of aspects for improvement... but I'm not complaining, it works a treat.

I wonder how much care a "professional" outfiit would take over it  :-\
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: Lazydocker on 19 December 2011, 23:41:35
Agree with Chris, but it all ended ok :y

Looks nice and tidy :y The only thing we have started doing differently (other than the butchery surgery on the interrupt wiring to use the big Vx injector plug) is take the vac reference from a tee on the servo line :y
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: JamesV6CDX on 19 December 2011, 23:44:20
Cheers Guys :)
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: feeutfo on 19 December 2011, 23:49:34
Where's the fuel line routed by the subframe...? We could do with some pics for the guide. Took some at Newent of Guffers but they aren't clear enough. Couldn't get the camera far enough away. ;D

And no need to drill the plenum, as LD says, saves some time there.  :)

Satisfying though. Mmmm 70p odd a litre. Waaahoooo!
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: JamesV6CDX on 19 December 2011, 23:53:22
I need to get under her in a few days for a little job, so I'll take a pic of the fuel routing :y :y
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: Lazydocker on 19 December 2011, 23:58:26
I need to get under her in a few days for a little job, so I'll take a pic of the fuel routing :y :y
I wonder if James has used the route we have had to start using? :-\
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: Kevin Wood on 20 December 2011, 00:02:29
Agree with Chris, but it all ended ok :y

Looks nice and tidy :y The only thing we have started doing differently (other than the butchery surgery on the interrupt wiring to use the big Vx injector plug) is take the vac reference from a tee on the servo line :y

This is what Gaffers did initially and the MAP was all over the place every time the brake pedal was pressed. Also, the MAP hit 100kPa at about half throttle. I did wonder if the brake servo was leaking (it held vacuum with the engine stopped for a good few pumps of the pedal, though). Be interested to know if there's any effect from the servo on other cars plumbed this way.

Still, looks a nice job, James. Second nature by now, though. :y
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: feeutfo on 20 December 2011, 00:24:06
Agree with Chris, but it all ended ok :y

Looks nice and tidy :y The only thing we have started doing differently (other than the butchery surgery on the interrupt wiring to use the big Vx injector plug) is take the vac reference from a tee on the servo line :y

This is what Gaffers did initially and the MAP was all over the place every time the brake pedal was pressed. Also, the MAP hit 100kPa at about half throttle. I did wonder if the brake servo was leaking (it held vacuum with the engine stopped for a good few pumps of the pedal, though). Be interested to know if there's any effect from the servo on other cars plumbed this way.

Still, looks a nice job, James. Second nature by now, though. :y
worth a look :y
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: feeutfo on 20 December 2011, 00:26:24
Agree with Chris, but it all ended ok :y

Looks nice and tidy :y The only thing we have started doing differently (other than the butchery surgery on the interrupt wiring to use the big Vx injector plug) is take the vac reference from a tee on the servo line :y

This is what Gaffers did initially and the MAP was all over the place every time the brake pedal was pressed. Also, the MAP hit 100kPa at about half throttle. I did wonder if the brake servo was leaking (it held vacuum with the engine stopped for a good few pumps of the pedal, though). Be interested to know if there's any effect from the servo on other cars plumbed this way.

Still, looks a nice job, James. Second nature by now, though. :y
worth a look :y
although both mine have been done that way, no issues attributed to it, iirc...?
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: Lazydocker on 20 December 2011, 06:14:57
Agree with Chris, but it all ended ok :y

Looks nice and tidy :y The only thing we have started doing differently (other than the butchery surgery on the interrupt wiring to use the big Vx injector plug) is take the vac reference from a tee on the servo line :y

This is what Gaffers did initially and the MAP was all over the place every time the brake pedal was pressed. Also, the MAP hit 100kPa at about half throttle. I did wonder if the brake servo was leaking (it held vacuum with the engine stopped for a good few pumps of the pedal, though). Be interested to know if there's any effect from the servo on other cars plumbed this way.

Still, looks a nice job, James. Second nature by now, though. :y
worth a look :y
although both mine have been done that way, no issues attributed to it, iirc...?
Mine done that way and so's TBE, both with no ill effects :y
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: Kevin Wood on 20 December 2011, 09:43:17
Agree with Chris, but it all ended ok :y

Looks nice and tidy :y The only thing we have started doing differently (other than the butchery surgery on the interrupt wiring to use the big Vx injector plug) is take the vac reference from a tee on the servo line :y

This is what Gaffers did initially and the MAP was all over the place every time the brake pedal was pressed. Also, the MAP hit 100kPa at about half throttle. I did wonder if the brake servo was leaking (it held vacuum with the engine stopped for a good few pumps of the pedal, though). Be interested to know if there's any effect from the servo on other cars plumbed this way.

Still, looks a nice job, James. Second nature by now, though. :y
worth a look :y
although both mine have been done that way, no issues attributed to it, iirc...?
Mine done that way and so's TBE, both with no ill effects :y

I wouldn't expect there to be, TBH, which is why I was a bit baffled by Gaffers' issue. We drew a bit of a blank, so put a nozzle in the plenum and, AFAIK, it has been fine since. I think there must have been a leak into the servo but, as I say, you could stop the engine, and it held enough vacuum for a half dozen pumps of the pedal. :-\
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: feeutfo on 20 December 2011, 09:45:20
Agree with Chris, but it all ended ok :y

Looks nice and tidy :y The only thing we have started doing differently (other than the butchery surgery on the interrupt wiring to use the big Vx injector plug) is take the vac reference from a tee on the servo line :y

This is what Gaffers did initially and the MAP was all over the place every time the brake pedal was pressed. Also, the MAP hit 100kPa at about half throttle. I did wonder if the brake servo was leaking (it held vacuum with the engine stopped for a good few pumps of the pedal, though). Be interested to know if there's any effect from the servo on other cars plumbed this way.

Still, looks a nice job, James. Second nature by now, though. :y
worth a look :y
although both mine have been done that way, no issues attributed to it, iirc...?
Mine done that way and so's TBE, both with no ill effects :y

I wouldn't expect there to be, TBH, which is why I was a bit baffled by Gaffers' issue. We drew a bit of a blank, so put a nozzle in the plenum and, AFAIK, it has been fine since. I think there must have been a leak into the servo but, as I say, you could stop the engine, and it held enough vacuum for a half dozen pumps of the pedal. :-\
not the old "servo pipe rubbed through on the ac pipe" favorite then...?
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: Kevin Wood on 20 December 2011, 09:47:39
not the old "servo pipe rubbed through on the ac pipe" favorite then...?

No leaks that we could find, and, as I say, air drawn from the servo was certainly making a  big impact. On hindsight I do wonder if the pipe was partially blocked.
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: TheBoy on 20 December 2011, 10:35:37
Happy to take any required pics of TBE, which obviously has been certified, first attempt.

How did you get on with certification JamesV6?
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: Lazydocker on 20 December 2011, 11:34:06
Happy to take any required pics of TBE, which obviously has been certified, first attempt.
Yep, or my estate. When it was inspected we had a bit of a discussion about a couple of things but it passed and they commented that it was far neater than any of their conversions ::) ;D :y
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: tigers_gonads on 20 December 2011, 13:31:09
Have any of you lads got any pictures of the mounting and plumbing of the KME Gold reducer on the 3ltr V6 ?

I had a right ball ache getting mine to fit down there and tbh i've still got some tidying up to do on that side  :-[
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: Gaffers on 20 December 2011, 13:42:13
not the old "servo pipe rubbed through on the ac pipe" favorite then...?

No leaks that we could find, and, as I say, air drawn from the servo was certainly making a  big impact. On hindsight I do wonder if the pipe was partially blocked.

MAP is still off a bit although it is steady now when you press the pedal.  I wonder if that is causing the misfire issue I have....

Not had the time to look at it properly yet as I have other priorities right now but the blocked line is a real possibility as the breather box pipes on the trumpets were blocked when I first got the car.  Yet I remember taking the line off and feeling the neg pressure in the t-piece and then unplugging the line next to the MAP sensor there was still neg pressure.  I suppose a partial blockage could be possible but then the MAP would just be slower to react surely rather than reading 0.08-0.1 too high.

By the way, who the f£$% is Gaffers?  ::)
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: omegod on 20 December 2011, 15:24:36
Agree with Chris, but it all ended ok :y

Looks nice and tidy :y The only thing we have started doing differently (other than the butchery surgery on the interrupt wiring to use the big Vx injector plug) is take the vac reference from a tee on the servo line :y

This is what Gaffers did initially and the MAP was all over the place every time the brake pedal was pressed. Also, the MAP hit 100kPa at about half throttle. I did wonder if the brake servo was leaking (it held vacuum with the engine stopped for a good few pumps of the pedal, though). Be interested to know if there's any effect from the servo on other cars plumbed this way.

Still, looks a nice job, James. Second nature by now, though. :y


Mine comes off the servo with no ill effect

Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: feeutfo on 20 December 2011, 18:28:58
Have any of you lads got any pictures of the mounting and plumbing of the KME Gold reducer on the 3ltr V6 ?

I had a right ball ache getting mine to fit down there and tbh i've still got some tidying up to do on that side  :-[
agree it is tight, and fiddly, with ltd access. Plues leaving room to get access to the allen key adjuster doesnt help.
Although dbw engine bay helps.
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: tigers_gonads on 20 December 2011, 18:57:26
Have any of you lads got any pictures of the mounting and plumbing of the KME Gold reducer on the 3ltr V6 ?

I had a right ball ache getting mine to fit down there and tbh i've still got some tidying up to do on that side  :-[
agree it is tight, and fiddly, with ltd access. Plues leaving room to get access to the allen key adjuster doesnt help.
Although dbw engine bay helps.


Tell me about it   :)

Pain in the arse  ;D

Has anybody totally removed the EGR side of the engine on a 2.5 / 3ltr engine and shorted out the plug on here ?  :-\
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: TheBoy on 20 December 2011, 19:18:24
Has anybody totally removed the EGR side of the engine on a 2.5 / 3ltr engine and shorted out the plug on here ?  :-\
TheDaddy...

I would leave the egr as-is...
Title: Re: 3.2 MV6 - My DIY LPG Conversion
Post by: 05omegav6 on 20 December 2011, 20:49:22
Quote
take the vac reference from a tee on the servo line

Is this taken from the Vac line between the servo and the Non return valve, or between the valve and the plenum :-\