P38A Prins LPG Vaporiser Heater Connections

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pwood999

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Guys,
I'm in the process of reconnecting the water system on my project car (1998 GEM's 4.0).

Any thought on Series versus Parallel water feed to the vaporiser ? The original LPG install has the vaporiser in parallel with the heater matrix feed & return, but the hose kit was mess. I have tidied it up a lot and got rid of kinks in the old pipework, but wondering whether to change to a series install, and get rid of the two tee pieces ?

The Prins install guide shows both options, but no info on which to choose or why ?

Pete
 
I would go parallel
Takes a fair bit of heat to vaporise the gas so your interior will be cold or you vaporiser will not get the full benefit of engine heat if interior comes first.
Or I could be talking rubbish
 
In parallel works just fine unless you have flow restriction due to furred up hoses/water galleries....or a weak ass pump.

I have seen some right bodged up water connections with hoses going all round the place....the best install I have seen so far happens to be on my L322 (with a Prins system) it is tee'd into the hoses directly from the water pump, and this way they are kept as short as possible.

Always try and keep you water runs as short as you can and tee into a pipe with the most flow....it is common to use the heater pipes as they are more accessible, but they also have restricted flow through them due to the restrictions of the heater matrix.
 
Mine's run in parallel. Vapouriser is T'd off the feed to the heater matrix, and back into the return from the heater matrix. I don't have any issues with the vapouriser getting cold, or the heater matrix for the interior getting cold. Flow seems to be OK.

I did have mine in series for awhile, and due to the hose layouts, and some of the adapters, I found that whilst the vapouriser got hot - the heater matrix/cabin air got luke warm at best.

Re-plumbed back in parallel when I put a new vapouriser in awhile ago, and back to toasty heat in the cabin - and no issues with the LPG side either.
 
Mine's run in parallel. Vapouriser is T'd off the feed to the heater matrix, and back into the return from the heater matrix. I don't have any issues with the vapouriser getting cold, or the heater matrix for the interior getting cold. Flow seems to be OK.

I did have mine in series for awhile, and due to the hose layouts, and some of the adapters, I found that whilst the vapouriser got hot - the heater matrix/cabin air got luke warm at best.

Re-plumbed back in parallel when I put a new vapouriser in awhile ago, and back to toasty heat in the cabin - and no issues with the LPG side either.

Welcome back, Marty. Guess your travels have been cut short?
 
Welcome back, Marty. Guess your travels have been cut short?

Thanks Grrrrr,

Yes, I was supposed to be away on tour until the middle of June - with another possible show straight after than until the middle of August. But as the entertainment industry pretty much evaporated overnight (it was like a switch for us - one night we were told of a few venues cancelling, and a week layoff at the start of April. The next day receiving a message that the whole tour was suspended until further notice!). Still we managed 2 1/2 months on the road, and I think the plan is to resume the tour once everything has settled down a bit and people can actually go out and about again - but who really knows how long that will be!

So I'm back home for the foreseeable future, trying to keep sane and do a few bits and pieces on P38s whilst I'm back... I have a pile of HEVACs, window switchpacks, and door latches to work on to put into stock that I've been piling up for the last 9 odd months whilst work has been busy!
 
Thanks Grrrrr,

Yes, I was supposed to be away on tour until the middle of June - with another possible show straight after than until the middle of August. But as the entertainment industry pretty much evaporated overnight (it was like a switch for us - one night we were told of a few venues cancelling, and a week layoff at the start of April. The next day receiving a message that the whole tour was suspended until further notice!). Still we managed 2 1/2 months on the road, and I think the plan is to resume the tour once everything has settled down a bit and people can actually go out and about again - but who really knows how long that will be!

So I'm back home for the foreseeable future, trying to keep sane and do a few bits and pieces on P38s whilst I'm back... I have a pile of HEVACs, window switchpacks, and door latches to work on to put into stock that I've been piling up for the last 9 odd months whilst work has been busy!

That Des O'Connor just keeps going, doesn't he?!
 
All plumbed in using parallel method. Pics to follow.
Now waiting for replacement radiator (delayed by Corona), because when I filled it with water the rad leaks all along the bottom where the fins go into the bottom tank.
 
All plumbed in using parallel method. Pics to follow.
Now waiting for replacement radiator (delayed by Corona), because when I filled it with water the rad leaks all along the bottom where the fins go into the bottom tank.

Any update? Any pics? I've got '03MY L322 with BMW engine (stop laughing!) Now I've had an engine re-build it seems to go fine. So am wanting to put back the '09 installed Prins LPG system. The reducer was bypassed to make sure LPG wasn't leaking into the coolant system and causing over pressure. AFAIK the reducer coolant hoses were just connected together.
I've bought new elbows for the reducer from Tinley Tech but don't know how to re-connect. But even when before my problems when I was running on LPG well, the heater never got warm or hardly at all

BTW there appears to be a gas connection adjacent to the filter unit. The diagram I found lists that as a connection to the "over pressure coupling" But I don't have any connection to it. Where does yours go?
Reducer-connectors2.jpg
 
Different engine & coolant flow, but sounds like yours is in series with heater.

Thanks for that. BTW, I've had good results from Boston Motorcool for rebuilding rads, recoreing and the like. Prices reasonable too. Last one they did for me was an XJ6 series 1. They'll increase the cores (mine was a two but they made it a three) if you ask, Richard Dilley there on [email protected]
 
Following helpful reply received from Tinley Tech:
"That fitting [open brass-looking one in the pic] is the outlet should the pressure relief valve in the reducer open (a very rare if not unheard of event), some people leave it open, some put a length of hose directing it towards the ground and some pipe it into the gas system vacuum feed pipe from the manifold.
If you choose to pipe it, you can just use some 5mm internal gas hose from our online store (and a 5mm T piece if you decide to connect to manifold pipe)
Regards Charlie tinleytech.co.uk 01767 676181"
 
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