LPG - modern cars too hot for converters...the way around it - simple!

[ozscott]

I have learnt the hard way with modern fuel injected engines that run hot for effeciency and emissions - its too hot for the converter to convert gas at a healthy temp...it cracks again to form more of the metholdecapthlen (not correct spellling - black goo) and it gums up the idle jet and diaphragms...and ends up causing backfires and poor running on LPG when cold. I have just installed a simple brass inline thermostat that reduces the temp in the converter down to 130-140f instead of 190+ normally...and all it does is slow the water flow through the converter/heater circuit to allow the cold gas to cool the converter water more which in turn cools the converter down...dead simple and bloody great! My 95 V8 suffers the same problems and usually sooner than the D2 so I am going to do it too. $100 for a brass inline.

All of this explains why my family and friends with carby 70s-early 80's vehicles on LPG never have converter gumming up...they run so much cooler.

This is a thread that should be for the benefit of all rover owners that run or want to run LPG and have hot motors...I am not going to go and post it on each thread though, so hopefully this will be read.

Cheers

[p38arover]

Info about the item fitted would be useful. Perhaps a pic or a link to the item?

[350RRC]

All of this explains why my family and friends with carby 70s-early 80's vehicles on LPG never have converter gumming up...they run so much cooler.

Hi,

I'm open minded on this. It might be something other than the temp.

AFAIK all the 70's & 80's cars would have been using the majestic cutting edge (*cough* 1950's tech) IMPCO convertors and mixers that could even let small birds through.

Don't get me wrong here, I have this set up on my 350 RRC that has done 400,000k's quite happily with only one convertor diaphragm replacement.

F 111's are awesome 50's tech too.

cheers, DL

[ozscott]

https://www.altfuel.com/thermostats.htm

...and Adam at Progas - knows his stuff and has shown me some evidence of it working very well on a late model Ford V8 fuel injected motor.

Cheers

PS. It makes a lot of sense to me.

[muddy]

Hi Ozscott
Thanks for the info

Do you have the contact details for Adam at Progas

Thanks

Maurice

[p38arover]

I'm also interested. I see the link is to a US site. Any idea of the Aussie price?

[ozscott]

Pro Gas (QLD) Pty Ltd
L.P. Gas & Natural Gas Equipment & Service - East Brisbane, QLD
Address
105 Norman St
East Brisbane
QLD, 4169
Australia

$100 - i have fitted it. That site above is a US site....cant see one in Oz

Cheers

[Gullible]

Is it the same situation for injection gas?

[ozscott]

yes mate because the injection injects gas that has been changed to gaseous state from a liquid in the converter...and it is capable of causing more damage than the mixer systems because it can get into the injectors. Liquid LP'G' systems...just coming out now in the hsv'S do not have a converter and as such are immune...but as I understand it they will not in the forseeable future be available for retrofitting.\\\\

[p38arover]

Is it the same situation for injection gas?

Can't see why not.

I've been thinking of restricting the water flow in mine as it bypasses too much heat around the heater. I was going to put the converter on the output side of the heater core (the coolant flows through heater all the time in P38A). If this was used, I'd have to leave the bypass configuration in place.

If there were a few of us wanting them, it could be worth doing a bulk buy from the USA.