LPG Forum


All times are UTC



Post new topic Reply to topic  [ 48 posts ]  Go to page Previous  1, 2, 3  Next
Author Message
PostPosted: Fri Jun 20, 2014 11:02 am 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7882
Images: 0
Location: Peterborough
I think the lack of threads is down to it being expensive for what it does. In some circumstances it may be slightly better than a mixer but is it worth the bother. Your car won't be direct injection, that's something that has only appeared in the last 4 or 5 years but even then you still need a throttle body, you've got to meter the amount of air going in somehow. Direct injection is where the petrol injectors inject fuel directly into the combustion chambers rather than the more usual method of injecting into the inlet manifold just before the inlet valves. This is what you have on yours currently. A multipoint system involves fitting spuds into the manifold next to, or as near as possible, to the existing petrol injectors so there is an injector per cylinder rather than you old system of introducing the gas at a single point by the throttle body.

_________________
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.


Top
 Profile  
Reply with quote  
PostPosted: Fri Jun 20, 2014 6:11 pm 
New member

Joined: Wed Mar 16, 2011 12:40 pm
Posts: 123
Location: North Essex
Disturbing the induction system on an old motor like this can only lead to tears, I fear.

My concern with the blos is that it needs be linked to an ECU system. A stepper motor before the gas goes in may not work as the blos would be some way from the throttle body. A link to the petrol system to ensure no engine warning light muast be essential contrary to the blurb. Awaiting sellers comments.

Why should the gas going in as though through a normal carb but as LPG and air and not petrol and air, burn out the Cats? OK, I can see that set up may be aand a bit trial and error and I don't have any details as regards the sellers instructions how to set up correctly to get peak settings. Only via laptop readings will it presumeably be possible to really recognise the two fuels and compare their performance and know for sure its properly set up. Is this an impossible ask?

I'm in awe of you professionals on this forum so forgive my playing devils advocat to all your advice. You menioned in an earlier comment on the thread egas (the local to me) and a solenoid going down destroying an ECU. Surely this applies to any multipoint system more so than single point. Eleven solenoids on a V8 system as opposed to three on single point. Risk factor? OK Safeguard fuse mentioned but are they fitted as standard? How many are needed?


Top
 Profile  
Reply with quote  
PostPosted: Fri Jun 20, 2014 8:32 pm 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7882
Images: 0
Location: Peterborough
Stu, how are you disturbing the induction system? You drill small holes in the manifold near to the petrol injectors and fit a nozzle that is connected to the gas injector. When the gas is turned off, they are blocked off so may as well not be there. There's less disturbance to the airflow than bolting a mixer onto the throttle body. That's one of the reasons they work better, you are doing less disturbance to the original intake system than fitting a single point would.

The Blos is in effect a carb that adjusts the mixture, but so will a stepper so you'll have two things fighting against each other. The Blos doesn't have any method of connecting to a computer, it's set up with a screwdriver just like adjusting a carb. There's nothing in it to connect to the petrol system to stop the warning light.

There aren't 11 solenoids, there's still only 3 as a maximum. Yes, the injectors are small solenoids but each one is fed from it's own circuit in the ECU so they each fire at the same time as the petrol injectors would fire if they were still firing. There is then a further output to operate the solenoids and it is this one that can die on the egas ECU. Normally, three solenoids would draw a total current of around 3 Amps (1 Amp each), but if one goes short circuit, it will draw far more than that and the ECU output burns out. The same could happen with any ECU if it wasn't designed properly and has no protection against a short circuit solenoid coil which, unfortunately it seems, the egas doesn't. On your Leo on the Merc the solenoids were switched by an internal relay so no strain was put on the switching circuit if a solenoid died (or a wire to a solenoid shorted out to ground) and it would simply blow the main fuse. The mod to protect an egas ECU is to add that relay and fuse. But the egas is in the minority, all of the others don't suffer that problem anyway.

_________________
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.


Top
 Profile  
Reply with quote  
PostPosted: Fri Jun 20, 2014 8:56 pm 
Installer

Joined: Wed May 23, 2007 5:51 pm
Posts: 8096
Images: 0
Location: Wiltshire
Stuzewheels wrote:
Why should the gas going in as though through a normal carb but as LPG and air and not petrol and air, burn out the Cats?

It's to do with accuracy.
By design, the cats burn any hydrocarbons left in the exhaust. Too much hydrocarbon (because fuelling is inaccurate) means they overheat - hot at the best of times, they burn white hot and meltdown.
A longer term, less dramatic issue, is clagging of the fine matrix leading to blockage. This can happen again due to fuelling inaccuracies, where the cats don't get enough fuel to burn at design temperature, and soot builds up.

I see no reason not to believe a Blos is more accurate than a conventional mixer, but that may not be accurate enough. It is only a glorified SU carb. You might reflect on why even the cheapest cars when fitted with cats use electronic fuel injection, despite the wealth of experience in making petrol carbs. Relatively crude injectors can be made fantastically accurate simply by using a closed-loop sensor system, and cheap too. A petrol carb would fry the cats.

_________________
www.blazegas.com


Top
 Profile  
Reply with quote  
PostPosted: Sat Jun 21, 2014 9:18 am 
New member

Joined: Wed Mar 16, 2011 12:40 pm
Posts: 123
Location: North Essex
Many thanks for helping me understand the issues here.
I'll bone up on the instruction manual to see if removal of the induction manifold is as difficult as I imagine it to be.


Top
 Profile  
Reply with quote  
PostPosted: Sat Jun 21, 2014 2:58 pm 
Installer

Joined: Wed May 23, 2007 5:51 pm
Posts: 8096
Images: 0
Location: Wiltshire
Depending on manifold design, there are techniques to minimise risk of drilling in situ:

Blob of grease on the drill tip just before break through - yuk, I would not trust that

Remove throttle body, steer a hose or plastic duct up the inlet port with a window in it aligned to the drill point. Attach a vacuum cleaner.

Find a vacuum port you can attach to a compressor, and lightly pressurise the manifold. You need a large compressor/tank to keep up with leak rate, and an adjustable valve to bleed in air at a rate to keep a sensible pressure.

_________________
www.blazegas.com


Top
 Profile  
Reply with quote  
PostPosted: Mon Jun 23, 2014 12:05 pm 
New member

Joined: Wed Mar 16, 2011 12:40 pm
Posts: 123
Location: North Essex
On the subject - this one amused me for several reasons.

http://www.ebay.co.uk/itm/Lexus-LS-400- ... 2ed3533081


Top
 Profile  
Reply with quote  
PostPosted: Mon Jun 23, 2014 2:06 pm 
Junior Member

Joined: Wed Jul 03, 2013 11:38 am
Posts: 225
Images: 0
Stuzewheels wrote:
On the subject - this one amused me for several reasons.

http://www.ebay.co.uk/itm/Lexus-LS-400- ... 2ed3533081


You looking at MY car?
Wiltshire - photo taken at Longleat?
Did the ariel work before his mate swung on it?
My area - I'm allowed to laugh at the locals - I'm one of 'em.


Top
 Profile  
Reply with quote  
PostPosted: Mon Jun 23, 2014 6:59 pm 
New member

Joined: Wed Mar 16, 2011 12:40 pm
Posts: 123
Location: North Essex
I know this will be vexing (with apologies to all) but got me thinking how many of those 340, 000 miles were covered on the single point system? OK how many head gaskets and valve changes, inlet conduits, etc etc. has the car gone through.
And this is a later model "w" reg.


Top
 Profile  
Reply with quote  
PostPosted: Mon Jun 23, 2014 7:55 pm 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7882
Images: 0
Location: Peterborough
Running on gas isn't going to cause a head gasket to go, it could cause valve seat recession but the Lexus does not appear on the Prins list of cars that suffer. However that may be because not enough have been converted for meaningful data to be available, as it is generally accepted that Japanese cars do suffer.. Not sure what you mean by inlet conduits but suspect you may mean the intake trunking. Who knows and who knows when it was converted, as you say, how many of this miles have been done on gas?

I suppose if nothing else, it does prove that an LS400 can be made to work with a single point although he does admit that it doesn't work particularly well. He also doesn't mention how many times it has gone pop either. I still wouldn't take the chance though.......

_________________
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.


Top
 Profile  
Reply with quote  
PostPosted: Wed Jun 25, 2014 1:43 pm 
New member

Joined: Wed Mar 16, 2011 12:40 pm
Posts: 123
Location: North Essex
I asked a few Q's.
Ad states he replaced the tank, which I think was installed in 2002?
He's never had a blowback but said that he has taken car revs up to 8000 which you couldn't do on multi injectors which would only go up to 6k. (not recommended in my book)
Looking at his set up he hasn't got the Vap North to South or East to West but its flat on its back or belly. Could be cause of his unevenness problem, I imagine. Standard mixer in throttle control body.


Top
 Profile  
Reply with quote  
PostPosted: Wed Jun 25, 2014 3:11 pm 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7882
Images: 0
Location: Peterborough
Stuzewheels wrote:
taken car revs up to 8000 which you couldn't do on multi injectors which would only go up to 6k. (not recommended in my book)
Say's who? Where did this 6k limit come from? With fast acting injectors using the correct nozzle size and gas pressure, you'd get them up to 8,000 rpm. There's been the odd Mazda RX-8 converted and they rev to 9,000 rpm.
Stuzewheels wrote:
Looking at his set up he hasn't got the Vap North to South or East to West but its flat on its back or belly. Could be cause of his unevenness problem, I imagine.
Maybe, more likely to cause rough running on bumpy roads though.

_________________
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.


Top
 Profile  
Reply with quote  
PostPosted: Wed Jun 25, 2014 4:05 pm 
New member

Joined: Wed Mar 16, 2011 12:40 pm
Posts: 123
Location: North Essex
Gilbertd wrote:
Stuzewheels wrote:
taken car revs up to 8000 which you couldn't do on multi injectors which would only go up to 6k. (not recommended in my book)
Say's who? Where did this 6k limit come from? With fast acting injectors using the correct nozzle size and gas pressure, you'd get them up to 8,000 rpm. There's been the odd Mazda RX-8 converted and they rev to 9,000 rpm.

Says he.


Top
 Profile  
Reply with quote  
PostPosted: Wed Jun 25, 2014 4:31 pm 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7882
Images: 0
Location: Peterborough
Who is he? Not the bloke trying to sell a car with an incorrectly mounted vaporiser?

_________________
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.


Top
 Profile  
Reply with quote  
PostPosted: Wed Jun 25, 2014 4:46 pm 
New member

Joined: Wed Mar 16, 2011 12:40 pm
Posts: 123
Location: North Essex
Not sure if it was his personal opinion or that of someone who helps him with the LPG side of things. Something about a limiter being on fuel injected systems if I understood correctly?? Anyway, irrespective of the accuracy of such comments the Car certainly has done a good mileage without a sophisticated system, it would seem. Without his permission I can't show his Vap set up. Lets see if the car goes beyond its reserve and sells. Bids seem to have stalled for the moment. There are a few negatives


Top
 Profile  
Reply with quote  
PostPosted: Wed Jun 25, 2014 6:24 pm 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7882
Images: 0
Location: Peterborough
The multipoint ECU piggy backs onto the existing petrol ECU so any rev limiting would be that fitted by the manufacturers in the Petrol ECU, the LPG ECU simply does what the petrol one tells it. That could be seen as a big downside to a single point if you are a 'spirited' driver. Most rev limiters built into petrol ECUs cut the pulses to the petrol injectors when they reach the limit that the manufacturer has decided is the maximum revs the engine components can stand, with a single point you could rev an engine to destruction.

Anyway Stu, we are going off on a tangent and not answering the original question. It seems that a Lexus engine will run on a single point although these days it wouldn't be recommended as there is something much better available. When only the single point was available lots of vehicles, such as your Merc and my P38, were fitted with a system that wasn't ideally suited but it works. Not as well as it could, but it works nonetheless. Considering how cheaply you can get a multipoint for these days, it would be foolish to save maybe £100 and fit something that won't work as well and will give poorer economy. The difference in price for the components would be recouped in a couple of hundred miles.

_________________
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.


Top
 Profile  
Reply with quote  
PostPosted: Thu Jun 26, 2014 9:10 am 
New member

Joined: Wed Mar 16, 2011 12:40 pm
Posts: 123
Location: North Essex
You are of course rights as to the cost of parts, but the V8 engine looks a far more complicated animal to me than the straight six Mercedes. At least with the Merc or a four cylinder car you can see the inlet manifold. Not with the V8 which means you have to be very sure of where to put the spuds if that is you know what you are doing in dismantling to get the manifold off to drill. the crud that builds up is like sand and getting the engine clean before start is not something I am experienced in doing. So, factor in a £1000 labour charge for someone else to do the job and the £800 car starts to look a poor choice especially after the £450-£600? Cambelt change thats booked.
I haven't ruled out M/P but it will have to wait until after our next trip to France toward end of July whereas S/P could be done before then and save me a £120 petrol cost. Have you installed M/P on a fuel injected Landie?


Top
 Profile  
Reply with quote  
PostPosted: Thu Jun 26, 2014 9:38 am 
Advanced Member

Joined: Wed Apr 09, 2008 9:00 am
Posts: 7882
Images: 0
Location: Peterborough
My step-father, who started me pulling cars apart in the first place (when I was 11), looked at my Range Rover V8 and said it looked complicated. Then I told him it's only two 4 cylinder engines bolted together with an inlet manifold joining the two together. I can have the inlet manifold off in half an hour. In fact, as all the bolts go straight down into the heads, they are easier to get to than on a straight 4 or 6 engine where you are fiddling around trying to get to the ones underneath. How easy it is on a Lexus engine I've no idea, I don't know what else would have to come off to get to it. A pressure washer would clean the crud off pretty quickly......

Not installed a multipoint but thought about it a number of times on mine and have intended doing it every summer since I've owned it. Now I've got a second one with a multipoint already fitted, I've pulled it off and put it back on to my engineering standards. If you are paying someone else to do the install, then it could get expensive although £1k does sound a lot.

_________________
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....

Proud to be a member of the YCHJCYA2PDTHFH club.


Top
 Profile  
Reply with quote  
PostPosted: Fri Jul 04, 2014 3:23 pm 
New member

Joined: Wed Mar 16, 2011 12:40 pm
Posts: 123
Location: North Essex
There are occasionally Sequential systems on ebay which have not been put in cars and are being sold cheaply.

Is it possible to use a V8 sequential system but linked to a single point stepper motor?

Price wise these bargains often compare favourably to Chinese stuff on sale. Just wondering, then If I decided at a later date to go full multi I'll already have the parts to hand?
Or are the two incompatible?


Top
 Profile  
Reply with quote  
PostPosted: Fri Jul 04, 2014 4:08 pm 
Installer

Joined: Wed May 23, 2007 5:51 pm
Posts: 8096
Images: 0
Location: Wiltshire
Stuzewheels wrote:
Is it possible to use a V8 sequential system but linked to a single point stepper motor?

No. Completely different operating principles. Bit like asking if horseshoes are any use on a racing car.

_________________
www.blazegas.com


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 48 posts ]  Go to page Previous  1, 2, 3  Next

All times are UTC


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group