Hi all as some know i rebulit the s-type power plant, well i did not like the drive of this car so its gone. now have a xj6 4.0 trying to look into using lpg so asking has anyone done this. it would be a diy install, £1.35ltr gas/£0.45ltr lpg. you can now see why. i will update my pics, what a babe this cat is my young son just started laffing when 120 came up on the dash in less time than he could say mcdonalds lol..

Looking forward to any help

 

Hi
I've got a 4.0l x300 running on gas. It was already installed when I bought the car so not much help there. But had some experiance with my last car. Try the LPG forum lots of helpful people on there only to happy to help.
Mine has a doughnut tank in spare wheel well I carry a space saver but I think you can just carry one of those repair cans if space is an issue. Definately the way to go although 45p does sound cheap its usually around 66p litre. Saves a fortune and you really cant tell the difference (apparently you loose 10% performance but you wont notice with a 4.0l) Go with the multipoint which means an fitting an extra injector to each cylinder also you will have to tap into the water circuit to warm up the gas. The wiring should be quite easy you pick up on TPS, Lambda, MAF and a few other things cant remember exactly what but you just tap into them to get the signal to the gas ECU. The petrol injectors are wired through the gas ECU so when you switch to gas it can turn off the petrol injectors (The car still thinks its running on petrol you see) I think its quite an easy job for someone competent but you will have to get it checked by an expert so you can get the insurance and possibly to set the gas ECU but I think its possible to set up yourself with a laptop.
Hope all this helps let me know if you need any more help.

 

well i have taken my time looking into runing on lpg,, it all looks good, only thing bad was the rumers of rubers failing( not true), as long as the unit is fine, its fine for lpg. this will be a diy install. i have picked up a used tartarini system i will start fiting next week. pics to come. by the way this should cost less than £100($150us)

 

Well done

just remember lpg runs hotter than petrol.
Also look into a flash lube kit.

 

yes been looking at flashlube kits around £25 to start with then £16 every 4-5week, i was chating with somone that has a landy and he has never used it in the last 10 years using lpg, must have good heads on it.

if anyone can shed more light on this i would be greatful.

 

IIRC the Jag V6 has sufficiently soft valve seats to need a flashlube (or equiv) system, but I've not heard the same of the AJ16. Mine's fine at any rate - touch wood!

 

The v8 landy's do have very good head however the bottem end is a diffrent story the cylinder liners slip.

is the kit you got a singe point or multi point. as theres a also a "thing" you can get to stop a single point blowing the intake to bits if it back fires.

 

Really intereresting stuff therave, I'll be subscribing and watching for sure.

I don't think we can offer too much hjelp with an actual lpg install here at present, but as suggested the lpg forums will offer much better assistance I'm sure.

If / when you go ahead with this, how about doing a "how to" for us c/w pics and a full write up?


This will be great for future members

 

yes will do, anyone know where i can pickup the rpm reference from under the bonnet(what wire colur)

 

Flashlube is only needed on a few vechicles. Mainly engines designed as lean burn. I've been installing LPG for 10 years till I retired and never fitted Flashlube. Sealey do a multimeter that has a RPM section, get the signal from the coil. Get rid of the modern plugs and find NGK copper core plugs. Close the gaps down to about 0.8. Hope this helps.

 

Sorry....its Draper not Sealey....about £12 on Ebay!

 

Sorry for asking what would seem to be a daft q.. forgot i could pickup the rpm at coil num:1(i think)

seeing as you have fitted lpg before what do you think to using polyflex for the tank fill/out it does meet 67r.

gunson's testune,,i had forgot i had this good for 8,000 rpm
dont know wether this will work with multiple coils though..

 

Yes, Polyflex seems to be ok, Romano now use a simular pipe for their front end kits. Its made in Italy, but I imagine its much the same. Your Autotune should be ok. Just check its showing the same rpm as the rev counter. Don't forget the spark plugs! If get any missfires in use aways suspect the ignition first as it needs to be tip top for lpg. I have had many owners phone for advice on missfires, me telling them to change the plugs, them not believing me but trying it anyway, then they phone back happy bunnies!!

 

I've tried signing up to lpgforum.co.uk a couple of times - my account was never activated, & the admin doesn't appear to respond to emails

tfjb1, as you're here...!

Mine's got a misfire on gas at 3.5k rpm - and it likes to cut back to petrol at high load/speed (eg accelerating at motorway speeds). Ideally I'd hook up a laptop to it & look for clues, but it (OMVL XXI-P) seems to be an awkward one to find a lead for. Plugs are new (but not gas-specific) but I didn't reduce the gap - worth a shot? Swapping the plugs didn't appear to affect the issue, but did fix a different problem!
The cutting out under load bit was leading me away from ignition related issues (I've had those on previous cars, so would have been my first thought too), but I'd certainly value your expert opinion!

 

Hi Ziggy, Sounds like you might not be getting enough gas. Try a new filter, I normaly change the whole unit rather than just the element. Dont buy lpg plugs their just a rip off! Get old style copper core. Incidently, we did an x300 that developed a missfire, it turned out to be the AFM. Good luck.

 

Hi yes i did get on the lpgforum thanks to this site pointing it out,,it would not let me join, till i set up a new e-mail with a .co.uk,,, there forum does not like .com .....
Anyway on to the lpg fiting looks to be going ok pipes tomorrow as long as it does not rain, thats one of the bad thing about the uk. I will do a full write up when i am done...

ziggy found this on f-bay
OMVL Dream XXI LPG / CNG USB Programming Interface kit | eBay

hope the forum dont mind the link,, its not mine nor do i know the seller..

 

Cheers for that - I'll sort myself out with a new (temporary!) email address - and try to get my IP address unblocked once I'm on!

That cable's for an XXI-N - mine's the newer awkward version! The vast majority of sequential kits use the same interface (some have different pin-outs and connectors), but mine isn't one of them it seems...

 

Same thought process as me! I've tried swapping the filters - replaced the gas phase one but ended up with the wrong filter for the liquid phase. It didn't look bad enough to be causing a restriction, but I'll try it (briefly!) without a filter to see if that's causing any problems...

No misfires on petrol, so I'd be surprised (but not shocked!) if it was something like an AFM. I've had injectors go bad before, but they tended to cause roughness at idle, so I'm steering away from looking there. I need to have a thorough check of vac lines etc, but then I'm onto suspecting things like the reducer / pressure sensor etc - stuff that I wouldn't know what symptoms to expect when they went wrong!