the propane or lpg . sits in the tank at 160 psi.the multivalve, mounted on the tank , combines a feed into the tank , with one way valves either end of the pipe , and a feed out of the tank , blocked by a solenoid valve. also there is a float on a arm for the fuel level sender .
when the lpg box senses a spark plug firing it opens the solenoid valve , and the gas goes down the 6mm or 8mm copper pipe to the engine bay .
here there is another solenoid valve ,a filter ,and then the pressure regulator/reducer. this receives the liquid high pressure lpg , and converts it down in two stages to atmospheric pressure ,which is fed via a pipe to the venturi ring in the inlet which creates a draw and the gas goes into the engine .
there is mixture adjustment by a overall sensitivity screw on the reducer , and a pk flow screw valve on the pipe to the mixer venturi ..also if the car has low vacuum there is a tickover bypass screw on the reducer that lets in a little gas to keep the engine ticking over at low rpm.
something i have found with this sort of system is if the mixture is generally right , then it can go a bit lean on pk torque and full throttle .
to try to stop this,there is electronics box called a AEB leonardo. this control a stepper motor valve in the vapour line to the mixer , and it reads a lambda sensor in the exhaust . it then moves the flow valve stepper motor to try to constantly maintain 14.7:1 afr , or lambda 1.0.
i had one of these in the magic greenhouse , so thought i would see how it works .
with my astra i run up to 17.5:1 on cruise , and 13.5:1 on full power , so this will be a bit of a compromise ,but its free ,and easy to fit ,just a wire to the throttle pot , and the lambda , and the stepper motor .
Well i only went and got a bit more done today in the 23c hot sunshine .
firstly i fitted the inlet for the tank ..
pretty straightforwards , with the flap on its all gone ..
an interesting thing to note about the flap , it has a very clever over centre spring on it so it stays open , or shut , nice .
oh... something else of interest is , the car was originally elephant grey , and you can see the flap is now gold ,but under it is the grey , so at some point i think my car was gold ....isn't that weeeiiirrddd !?
next ,now i was onto a sweat soaked roll , fitting the reserve tank .
this beam needed straightening ..
so i gave it some herculean blows with the big long handled sledge hammer ..molnierrree ....and it decided to go straight ,like a newbie from wormwood scrubs.
it may not look it, but it is now straight .
next on the agenda , was the inner boot floor bracing strut ..
that ^^^^ poxy bit of metal , was a right palava to get off , it was about a foot in under the floor , and i could only cut one side , then try to lever it down and cut the other side ,don't know what its made of but i went through 2.5 s/s cutting thin discs .
anyrdUP , i could now pop in the tank ,and cut the hole for the lid ..
and fitted ..sort of ...
the other 90 litre tank , will sit at the back of the boot up against the seat back , and so i will have a 132 litres -20% total fuel capacity.
so then came in for lunch , and in the afternoon put the final layer on my rubbed down dash bits ..
so a hot time in the morning then a cooler time in the afternoon ,but all striving to towards a common goal
Your skills and resourcefulness never cease to amaze me.
I've looked at LPG before when I had a 3.8 S-Type Jag but I didn't get it fitted in the end (long story).
Do you find that there are many stations selling LPG now or is it a case of having to drive a while to find one?
Does it make financial sense (I guess it does if you already have a lot of the components :-).
Thank you very much Homer , much appreciated
Re stations , at the moment i have to go 10 miles to the stn , and its 73 pence per litre , when they finish refurbing my local on it will be 5 miles and 65 pence per litre . in the astra i have about 200 miles range , so wherever i go i can fill up on the way if needed ,there's a good website call filllpg that shows location and price .
re usage i get around 25 mpg local and 30 mpg long distance , but it is a bit tuned ,if i go slow i get 35 mpg , i went to Bury, 165 miles away , to fetch my welder ,and did 33 mpg on the way .carrying a 550 lbs welder in the back .
so i am around 9 to 12 pence per mile over all.
getting that parts from the scrappy or ebay , means the install costs v little , i picked up a full tank at the breakers for 30 quid for example , it actually had more value in gas inside than the cost of the tank , which i thought was funny.
cost of the installation depends on the level of complexity of course , a simple mixer ring ,very old skool , is cheapest,and will be a little more restrictive on power ,and so on , right up to a fully sequential injection setup , much more expensive ,but drives like normal .
some people use a blos mixer/carb , on injection engines , and that seems to work well and be cheaper than inj but better than a mixer ring .
with Medusa , i am limited for tank space , since i wanted it to fit insde the tail ,and be invisible, to keep the lines of the car smooth ,so i have a 11 gallon tank , and seem to be doing around 10 to 15 to the gallon , so a range maximum of 165 miles . i did 80 miles and it cost me 18 quid ,so it makes the car usable and not horrendous .That uses a megasquirt ecu to run two separate engines with one ecu ,it was suggested on the ms2 forum i was asking too much of a ms2 to do this , but it works. i think there is more economy in there with some more fine tuning/slower driving ,lol.
yes ,from what i can tell the tanks are off and being cleaned at a lot of stns , and also a problem at a refinery has dropped lpg production....
from another forum ,
" Apparently the refinery that supplies the majority of Propane had a problem at the beginning of last week. Rather than the 1000 tonnes per day that they would normally supply, they are down to 150 tonnes a day until a faulty valve can be replaced. They are having to decant bulk gas off into smaller tanks and fill the tankers from them. My local depot normally has 14-15 bulk deliveries a week and they are down to 5. They expect things to be back to normal by the end of this week or early next week."
LPG supply is declining especially with shell pulling out, my closest is now 12 miles away, I have pulled it off the TR7V8 because I tend to use t locally, it's not to bad on petrol anyway and the weight and restriction were an issue. On the Range rover (3.5 EFI) I don't really care about performance (it slow anyway) and I find LPG useful to keep the costs down when going further afield. Both had Blos mixers fitted with omvl r90e vaporisers fitting the blos transformed the Range rover.
I do have a lambda controlled system somewhere but the blos worked so well I didn't bother, I was wondering if AFR could be read out of the laptop interface which would make it a cheap way of measuring AFR, one day I need to dig it out and have a play.
i drilled the tank mounting holes ,and big pipe/vent hole, and that all worked out dead in line which was a nice surprise ..
i used a bit of silicone for the vent pipe , this is be sure if any gas should ever leak it will exit outside the car .
i then had a right palava trying to bend 8mm copper pipe into the contortion it needed to screw onto the valve ..
turned out my used 8mm pipe was swollen to 8.000001mm , and this meant a lot of work to get the olive on and the fitting on ,but in the end ,after standing like a question mark for ages i got er done..
phewf! ... i definitely don't want to do that again .
i spent a fair while under the car , and , without it jacked up , i was uncomfortably close to the spider web city of dread ,bear in mind i have found 5 seperate false widow spiders under there when doing the brakes , and got bitten 3 times,by one of the little bastards ,and those bites are not at all funny ,so i was not enjoying my little test of courage under there today .
But hey , you shouldn't have joined up if you cant take a joke .
tomorrow i crawl under again for the 6mm pipe to the front of the car .
Thank you EO , that makes all my spider bites worth while
SPEAKING OF WHICH ....
i only went and got the other pipe , the one to the engine , fitted ,and yes it took an hour and half just to get the fitting to screw into the multi valve , i even had to use a tiny thin file to rebuild the thread on it ,but hey ho, its in now .
And yes i did get bitten lol , not sure by what, but a 2" white circle with a red dot in the middle came up on my shoulder blade this afternoon , bit of germolene and its now red so i think i am ok .
i went along underneath zipping up the gas pipe , and also i found a bit of 5 core flex , so zipped that in as well , that's my wires for the flow cutoff solenoid , and the fuel level sender .
all that gubbins ended up in the engine bay , so i connected the 2nd cutoff/filter to the pipe , and then that to the reducer ,, so that's all the feed done. And the wires ready to connect to the leonardo gizmo.
here's a truly momentous piccy of the tank with its lid on ..
RE the leonardo , it needs a 0-5v signal from the throttle pot , but , since i have an ecu, i have no 5v supply , so i found a little 3 quid box on ebay that takes 12v and moves it down to 5v, so i can connect that across the throttle pot and have a 0-5v signal.
lastly i was curious about that gold colour on the filler flap , so i cleaned it back to see what colour the car used to be,and you can also see the original elephant grey too..
i don't think i will be using either of those colours , but it's all history , and not to be sneered at !
Well , health is fine ,so you an all breathe a huge sigh of relief , my nonsensical demonstration of determination over skill will continue.
For Those that get bored of piffling electrical work ,look away now ....it's down hill from now on .
since it was baking , i decided to work on the loom inside the car/oven .
i fitted an ignition switch , you know , the one i butchered a while ago..
and after cleaning and wiggling the handbrake switch , i got two lights on ..
those are the choke warning light , and the handbrake warning light .
all well and good you may say , as did i ,however ...wheres the ignition light ??
i hunted ,and i probed , and i replaced bulbs ,but nuffin ...then i looked at the diagram a bit more and realised >>THERE ISN'T ONE !
how weird...just an ammeter , no light. so i think i will re purpose one of the lights, prob the choke one , and have that as a ign light . i mean ..really.
next i worked on the ammeter , its needle was thusly..
and it should be central.
i took it off and apart ,and feeling the needle flobbly dobblyness , or as its known, its flowerpot men factor F.M.F ...decided it had got bent. so i bent it back to vertical (that's what she said) ,
and then put a load on it , with a headlight bulb to see if it moved ..
there is it with 3.94 amps , and here it is with both bulb elements on ..
and 8.26 amps , so it is moving .back onto the car it goes.
next was do i have power to the starter solenoid , er , no i don't.
was it the gearbox isolator switch ?..... its job is to prevent the car starting in gear , and running your foot over .
i had a look at it ,
and it really does not look very well , but then upon further investigation , i realised that it could be a
pickled gerkin for all the good it was even going to do,since a few inches along the cable to the
dashboard was this ..
YES , that is the diagonal cut in half cable , that would stop it ever cranking ...ever.
now looking at the angle of cut , i deduced it was cut by a left handed man , 5'2" tall , wearing a greasy blue boiler suit , and a flat cap . ..looking at it more closely it was obvious he had a rag in his left hand back pocket , and had just lost a pony on the dogs the night before at crystal palace ,and had drowned his sorrows at the local with 11 brown ales , and a half pint of gin .
He had woken up with a hangover , and a class grudge , which he took out on this car ,since it was owned by "some stuck up toff" who he , "would not waste the time of day on " and also "who would be the first against the wall when the revolution came"
this also explains the ht leads in the wrong order .
i found a bit of red two core flex taped up int the dash area , which looked like this ..
i know ..i know.... exciting photo of the year right there .
it was connected here..
thats across the earth from the dynamo control box , and a permanent live fuse end ...nasty.
oh . i lied , one more bit of deviant behaviour... .
i realised the foot operated dip switch was missing , and could see no wires in the floor hole ,but then spotted this ..
it's a switch with three wires that appear to go down to the floor area by the gear mechanism , so maybe its a retro fitted or factory dip switch , maybe the bloke who bought the car only had one leg ??
tomorrow i do a careful inspection of the seat cushion for a stump indentation .