Good result in the end and an interesting thread.
This thread is on subject.

MOT emissions procedures give LPG users extra leeway which is to our advantage but, as Morat implied, we still want DVSA to expect vehicles running on LPG to have cleaner emissions than petrol vehicles because if DVSA strongly enough suspects LPG emissions to be dirtier than petrol we may eventually not only lose that advantage but also have to jump through more hoops than unconverted vehicle users and/or duty on LPG may be increased.

If DVSA ran emissions tests on a number of LPG vehicles selected at random it's likely that a fair proportion of them wouldn't pass a petrol spec test. They might then think up a number of ways of addressing the fact that for so long they had presumed LPG emissions to be better than petrol emissions but had now found this not to be so for a fair proportion of LPG vehicles. Out of all ways they could think up the best outcome for us would be if they evened the playing field between MOT petrol and LPG emissions tests and considered this all that they had to do. Most of us would find this preferable to DVSA and government saying 'This is what we've found, this is where we're at, you can keep the carb MOT test limits but we found LPG isn't as clean as we thought and therefore we will increase duty by 15p per litre gradually over the next 3 years'.

I'm watching this thread but nothing to add so far, I think Gilbert knows more about MOTs than I do.

Whenever I read the words 'Summer camp' it reminds me of 'Summercamp' walky-talkies my dad bought from Exhchange & Mart when I was a kid before CB radios were around.

super4 wrote:

Yes - very smart - P38 isn't bad either............

They call me the wanderer, yeah the wanderer... lol ;-)

Sloth wrote:

If you replace any fuel line, get some decent Codan R9 stuff or something, not the generic crap available on eBay/Halfords etc...

Or LPG stuff suppliers whom I've warned many times about supplying 'fuel injection spec petrol hose' that bellows like a balloon if subjected to more than about 1 bar pressure. Which they've done nothing about.

ECU would be fine tbh, for it to cause a problem in an emergency the bonnet would probably have to come off first and at that point a flying ECU is probably the least of your problems. But sure it's easy to make a hole through the plastic box and stick a bolt in, easier if you've got small hands or use a bit of grease/wire/elastic band to hold the nut in position. Live wire to battery as you'll have connected the injector live (ignition live) up at same time as wiring the injector breaks? I don't remember what injectors / nozzles / pressure you went for?

Now most aspects have been discussed... I don't much like the type of heated screen that has micro-elements between lamination that can obscure vision under certain conditions, for the few days per year we get where these are a definite advantage I prefer not to more often suffer the drawbacks. If heated screen means a couple of elements running over the wiper area that seems a better idea. Best setup I had on a car was the wiper area of screen heated coupled with heated water jets (and a large dose of antifreeze in the washer fluid) on a Vauxhall Senator, but got to worry about warm water jets hitting cold windscreens.

Sort of thing that winds my key too.
I suspect he'll have thought sod it, you won't be testing the heated windscreen for a good few months and by that time may think the heated aspect has failed but no big loss and not do anything about it. Windscreen fitter but hates messing with 'lectrics.

That's good to know Miles, I'd forgotten I'd done you a further advice bit.

Wouldn't want anyone else who's car I've converted to think there's a problem with their fan. Tried to be helpful with the fan thing, I know I did notice a noise on a P38, had it in my head that it was a fan, maybe I remember wrong and thought it was the idler pulley at the time. Checked to see if I made any notes on this (I sometimes make notes on cars I convert, either tech aspects of how I fitted/setup the LPG install that might speed up conversion of the same model next time or if I find an issue with the car itself) but didn't make any notes. Sometimes I'll put a 'further advice' section on the receipt (only if I think the customer would want me to do that, some wouldn't for obvious reasons) but I didn't put an advice section on the receipt either.. So can only go on memory which seems to have failed me this time!

My last edit crossed with Marty's post.. which seems to rule out the vac line scenario.
I've posted my suspicions etc about a TV fan on a P38 I converted recently and talked in general terms about things like LPG reducer and alternator noise, to prevent confusion and aid readability it's time for me to step aside and let P38 experts talk now :-)

Totally agree with Gilbert.
The one I noticed wasn't fully seized but seemed to be 'going that way', overly grabby. Weather was cooler then but did it from cold.

Whistling/whining? Another thing might be the alternator.

Have you listened around the engine bay?

Got to say/agree I can't really see you mistaking a 'whistling' around the dash with a TV fan or alternator noise. Ferryman's vac line scenario seems to fit the symptoms the most.

RutlandRover wrote:

Not mine was it?

Might well have been, I haven't converted loads of P38s lately, yours was one I converted.

Edit - Mind you I'd look a t*** if having just said TV fan it turned out to be the LPG reducer whistling! Make sure it doesn't only happen when running on LPG.

The main engine/radiator thermo-viscous cooling fan seized up? I noticed it seemed to be going that way on one of the P38s I recently converted...

A whistling noise from a vac leak would get quieter with decreasing manifold vacuum / increasing engine load (quieter when you put your foot down).

I've made throttle pots for carb engines I've converted to LPG. A short bit of rubber pipe between the spindle and pot can act as a CV joint and prevent lateral loads on the pot. Pots that turn through only 90 degrees (like the spindle does) aren't that common, you couldn't just use the original 5v supply (for a TPS) to a pot that has a different range of movement and get the same extent of voltage range out of it that the original TPS would give. But you can use a different supply voltage or load a pot's output using pullup/down resistors to give same range of voltage and same response curve as an original TPS. May be a problem replacing fly by wire throttle bodies on current cars when they become classic but at least this won't be a problem for P38s.

Doh! I should've refreshed the page before continuing to write a reply after breaking off in the middle of writing it.
Seems a good chance a broken pump was the cause of the engine not running earlier?

Lots of possibles with this one.

The coil could have been melted if the Leo's rpm wire (which will connect to a coil) shorted to earth at some point, may be worth checking this wasn't the case, could have accidentally fixed such fault changing the coil pack.

Can't remember what fuses run what on a P38 but shorting a coil pack to earth could potentially blow a fuse that runs some aspect of the petrol system, probably unlikely because would expect a relevant fuse to run the ignition (so wouldn't run on LPG either).

Emulators as Gilbert said.

Only other things that spring immediately to mind for this are forgetting to plug in the MAF (or ducting) / If an emulator isn't used (and yellow wires are used to disconnect petrol injectors) an issue in the Leo might have first caused the coil to burn, might now be causing Leo's relay (that joins / breaks yellow wire connection) to be unable to join yellow wires.

There are all sorts of ways of disconnecting petrol injectors if emulators are not used, yellow wires can be used directly or control a relay / a relay could be controlled by the blue wire.

Check positive feed to petrol injectors, check negative pulse at petrol injectors.
On either Gems or Bosch the fuel pump relay is switched by the petrol ECU which provides the relay coil's earth. I've known the petrol ECU to work perfectly except not provide the negative to the relay so the fuel pump never runs so obviously means it won't run on petrol (but will on LPG)... You've already ruled this out, I mention it because I was once called out to fix a P38 that would run on LPG but not petrol which (if memory serves) they said had recently had a failed coilpack. Wonder if a shorted coilpack could cause the ECU to fail in the way that sees it no longer provide the fuel pump relay coil earth. Discussed this with Gilbert before, he said he's known a P38 ECU to fail in the same way too but I don't know if that was after a failed coilpack.

Question in the topic name. I don't think I've untracked any threads I've been on yet.

So far this year I've converted about 10 vehicles from Scotland and another 10 from as far South as Devon, London, one from Southampton (out of a total of about 60 I've converted so far this year). The Jag I've just done is from Scarborough (100 miles) and the Elgrand that's just been dropped off for conversion is from Leicester. Got another coming in to convert on Wednesday from relatively nearby Chesterfield. One I'm converting next week is from Aberdeen.

I like your term 'concentric' far better than the 'inny outy' term I've been using hehe.

Both pipes have to be blanked off and there can't be any flow between them. At one point I tried something similar to what you've suggested, I cut the outer pipe back to get access to a length of the inner pipe long enough that heat from trying to braze the outer pipe wouldn't re-melt the braze on the inner pipe or vice/versa. The braze has a lot of surface tension but still wants to roll away into the pipe or spill out the end. Tried various takes on this such as partially crimping both pipes just below where the braze needs to take / tried to braze a large self tapper into the inner pipe. Dare say a grub screw would prevent braze running into the inner pipe but would still leave the problem of the outer pipe. Could try a cap with a hole drilled same diameter as the centre pipe to braze on but the problem with this is that the centre pipe is attached to the outer pipe at 3 points that run the entire length of the pipes and cleaning the inner pipe up to make round to make for a neat hole in the cap would be very difficult.

I'm wishing i went with something like JB Weld / quick metal / etc when the issue was just a pinprick in a simple narrow length of pipe (after the concentric splits into 2 pipes).

Might have been having another crack at it now if it wasn't for having to finish this Jag conversion off today. If I'm very lucky the guru fella will come back to me soon and say he can get the short section of pipe I need from Nissan in just a few days... But realistically it'll probably be £400 and 2 months just in time for autumn lol.