Which LPG mixer? 1963 1098 saloon on SU carb

[bigwheels]

Hello, I'm about to convert my Morris minor to LPG I have parts on order and a suitable tank but I have not got a LPG mixer to bolt in between the carb. I'm just wondering if anyone can enlighten me as to which LPG mixer I require and ideally point me in the direction of a supplier. Its a 1963 1098 4 door salon running a stock single SU setup with an unleaded head. I have gathered there are a few members on running LPG I would love to hear from them and get a few installation tips etc.

Regards Dave

[MarkyB]

Something like this I guess;
http://www.ebay.co.uk/itm/LPG-mixer-ass ... 1025018576

Putting SU into the search suggests it's more often done on larger engines.

You could always get this one and drill holes to suit the carb, it's a bit too big though.

http://www.ebay.co.uk/itm/SU-HIF4-LPG-M ... 337bc3afcf

[kevin s]

Or even better splashout £100 on blos variable mixer (just search on blos in ebay) , they are superb and give better fuel consumption and power, I have had one on my Landie for a couple of years now, you will need to add an elbow and some trunking to the carb to connect it though.

My Tr8 has the second type mentioned above, they are a bit restrictive and can be a bit touch and go at low RPM / idle though.

Kevin

[bigwheels]

I do have the option to have one fabricated, I just need to send the dimensions to an ebay seller but I was hoping somebody on here knew which mixer would fit to save me taking things in bits etc.

[grumpydad]

the best people to go to are Tinley Tech
will all wase help you over the phone
do fit a valve saver kit as well
have a look hear for mixers

http://www.tinleytech.co.uk/acatalog/Mi ... stems.html

[estwdjhn]

Or even better splashout £100 on blos variable mixer (just search on blos in ebay) , they are superb and give better fuel consumption and power, I have had one on my Landie for a couple of years now, you will need to add an elbow and some trunking to the carb to connect it though.

Seconded. BLOS gas carb is basically a SU for gas. Very simple effective bit of kit. The only better option is LPG over efi via a mega-squirt controller or similar, but that sort of system is much more work and cash...

[bmcecosse]

Interesting ! Do let us know how you get on - a write up of the complete installation would be very welcome.... LPG IS the way to go. I deeply regret turning down the chance to buy a complete kit from a Minor, a few years ago now. To compensate for the drop in power with LPG - I would fit a larger 1.5" SU carb, and if possible, raise the comp ratio by skimming the head, or (better still) fit a 12G 940 head from a 1275 engine.

[bigwheels]

Update - So far I've emailed Tinley tech for mixer advice and await their reply also I will document the process of the installation as my morris has a facebook page set up buy the previous owner that I frequently contribute too as the new owner. New members are always welcome https://www.facebook.com/groups/130682716961086/

[bigwheels]

further update - I have been in touch with tinley tech and afer a little deconsrtuction and reconstruction of the air intake and a few pictures were emailed to them and dimensions taken, they have recommended this mixer but it may be 5mm over spaced for the two mounting bolts but they have advised me to file down a bit each side . Anyway I have just placed my order and will have to see how it fits when it arrives!

They were very helpful and quick to reply:-

Thank you for the info,

The mixer we have is slightly bigger – you can see it right in the middle of the page below (it is listed as an ‘SUHS6’ mixer) – the mounting holes are 65mm centre but it should be an easy job to open them up slightly to fit.

Unfortunately we do not have a 360/55 frame but have a 360/60 which will only be a few mm longer.

Regards

Charlie.

here is the link:-
http://www.tinleytech.co.uk/cgi-bin/ss0 ... ACTION.y=9

]

[MarkyB]

This seems to be the issue with off the shelf stuff, it's all for bigger thirstier, engines.

My interest was peeked many years ago when a chap in a Morris Minor got nicked for driving with a gas bottle in the back and the pipe just running via the gutter into the carb!
Probably for pinching the gas bottle, I don't think that 5mm either way will make a noticeable difference.

[bmcecosse]

If it's for a 1.75" carb - then I can't see it working well even with a 1.5" carb and even less so with the standard 1.25" carb!! If it's all you can find.....then I would use it with a 1.75" carb - HS6 or HIF 44 although obviously the float advantages of the HIF model are not going to be used!
Can you explain to me/us how you then regulate the feed of gas into the mixer - to keep the fuel/air mixture correct?

[bigwheels]

This seems to be the issue with off the shelf stuff, it's all for bigger thirstier, engines.

My interest was peeked many years ago when a chap in a Morris Minor got nicked for driving with a gas bottle in the back and the pipe just running via the gutter into the carb!
Probably for pinching the gas bottle, I don't the 5mm either way will make a noticeable difference.

A truly great story wish I had seen it in the flesh

Yes you're right LPG parts are very available for big engine cars as they are the most economical to convert to LPG so they get produced as they sell well = good business, small cars with LPG conversions seem to be rarer than hens teeth in the classifieds, this does throw up a few problems up though when sourcing essential parts for the conversion!

I've been looking for a used LPG tank for a months as the new ones were expensive, the problem was I couldn't find one small enough for a Morris Minor that didn't cost the earth and wasn't a million miles away to collect from an Ebay seller as no couriers will touch them unless they are unpressurised with the valve removed (my patience paid off and after a seventy mile round trip I had one!).

I have most of the LPG parts including the tank now in stock, The rest of the kit is brand new from Poland (made in Italy) where most of the LPG parts comes from. I've just got to wait for the mixer and tank frame to arrive then I will make a start on the conversion as I need to see how it all pieces together and probably do much head scratching etc. I'm looking forward to having the car finished more than the process of converting it!

Personally I think daily driver Morris minors are ripe for converting to LPG as with cheap insurance for some drivers, like me, free road tax and the frugality of an LPG conversion on the motorists side it should be cheaper to run than the cost of an annual bus pass for the DIY mechanic like me who strives to totally avoid garage labour costs. The only downside I see is the maintenance and upkeep of the vehicle as the bus company takes care of that with the bus pass option but you also have to wait for buses and are restricted to their service routes with heavily reduced services on Sundays and Bank holidays!

[bmcecosse]

The tanks have a limited 'life' before they MUST be tested and re-certified.... And the installation must be inspected and approved before use on the public road. Your insurance Co should insist on seeing the approvals....
I'm still mystified how the flow of gas is regulated to match the air flow? Does it work on throttle position - or inlet manifold vacuum? Obviously on modern cars with ECU etc - it's all done very accurately via the electronics and the Lambda sensor - but on a carb car??

[MarkyB]

I believe it's inlet manifold vacuum via an on demand valve.
How often do gas bottles have to be re-certified?
Are insurance companies interested in knowing anything beyond the conversion? even if they "should" be.

[bmcecosse]

Dunno marky - but gas bottles DO get checked/recertified - the last date will be stamped on the bottle. Obviously while with a customer, the Co has no control over them - but they won't re-issue a bottle unless it is 'in certification'. As for Insurance Co - they do require you to tell them about any non-standard modifications. DVLA must also be informed about any change to the fuel type.

[MarkyB]

A bit of research suggests that E-marked tanks are date stamped and known to be factory tested to standard, so it is safe and sensible to assume the ticket validity from the E-mark date alone.
The ticket is valid for 10 years so there is a definite "sell by" date on second hand LPG tanks.
Uneconomic to get them recertified it's said.

[bigwheels]

I have had three modern LPG vehicles over the last decade and currently own a Jaguar xj6 on LPG, no insurance companies have ever asked for any certification for the LPG systems and they have all been declared LPG modified for insurance purposes sometimes it costs a little extra, sometimes its a freebie , just depends on the insurance company but I like to compare the market every renewal time!

Re:- The mixture, the vaporiser has two adjustable controls on my new LPG system for gas flow only to enable the minimum flow at engine idle and the maximum to be set at 3500rpm this is purely for economy as too much flow will use more LPG according to the booklet that came with it.

The mixer ring I have ordered from Tinley tech also has a mixture adjustment on it for gas / air ratios.

I'm not sure about tank sell by dates, but the tank I have got is full of gas so it effectively cost me nothing as the gas inside is worth more than I paid for the tank , I will definitely be using it for system test purposes!

[bmcecosse]

Excellent! I'm just trying to find out how you get round the various 'snags' of a DIY LPG conversion. More power to your elbow - and keep me/us up to date with progress please! So - is there any electricity involved in your conversion - beyond a switch to cut the fuel pump, and open the LPG feed valve ?

[bigwheels]

I'm just at the thinking stage and gathering parts at the moment,

But in my kit I have a fuel cut-off solenoid to put in line for the petrol supply to the float chamber this will still leave the fuel pump live though but I think it will be ok as its the same principle as a float valve. I have considered putting a relay in line with it so I can totally electrically disable the petrol fuel pump when running on gas but this may be overkill as its no different operationally to the existing system of a float chamber and valve.

Electrically the kit is very basic with a three stage switch no modules or laptop plug in facility just a switch for petrol, no fuel and LPG. Electrical connections need to be made to solenoid cut off for LPG, vaporiser solenoid, and petrol cut off and LPG tank valve. Ignition coil negative and +12V

I also noticed that the heater tap at the rear of the engine will need to be ran open to provide a hot water supply to the vaporiser in order to pre heat the LPG - I've had an idea to disable the heat in summer though using a bit of 15mm household plumbing kit to form a basic manifold and install a secondary heater tap so I don't cook in summer as my heater is very good one, since I painstakingly took it to bits and removed all the crud from the heater radiators internals last year.

This is the kit I have bought:-

http://www.ebay.co.uk/itm/car-lpg-duel- ... true&rt=nc

[bmcecosse]

I would definitely switch the petrol pump OFF when not in use.