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aboard_epsilon
04-16-2009, 07:48 AM
Knowing bugger all about this ..and not willing to spend 100 plus each for new injectors ...or 10 each for so called refurbished (cleaned) injectors

i intend to make a vessel ...to test fuel injectors ...one at a time .

I'm more interested weather i can clean them with ultra sonic tank whilst pulsing them with DC and stop them dripping, than the spray pattern ..sinse my car runs on LPG not petrol.

so have a look at this diagram ...it wont necessarily contain petrol ..maybe kero

http://img.photobucket.com/albums/v190/aboard_epsilon/vesel.jpg

all i have is "dry air gauges" so cant measure the liquid pressure ..

1...will the air pressure multiply or decrease the hydraulic pressure
2 can i expect around about 45 psi out of liquid pressure to the 45 psi of air ..
3,if not what air pressure into ...a vessel.........(you can make up the size of vesel) ..will be required to get 45 psi out the other end.

BEAR IN MIND WHEN ANSWERING ...

that my supplies are limited to max of 3 inch or there abouts diameter thick walled pipe for the vessel....and max air pressure I'm willing to give to it is 90 psi

all the best.markj

Mark McGrath
04-16-2009, 08:12 AM
You will get 45psi out.

digger_doug
04-16-2009, 08:43 AM
What kind of pressure do you want ?

Why not a gear pump driven with an electric motor ?
Kero lubricates enough for a gear type pump (I believe)

Maybe get a used power steering pump from the wrecking yard,
lower down the pressure relief setting.

why not a carbonator pump ? also used as water pumps
on tig torch coolers, but the proliferation of soda fountains
has lowered the cost on these.

The air tank system, look at a paint pot, ready to go,
has a quick opening top for filling, and has a safety valve
built in.

derekm
04-16-2009, 08:43 AM
To get pressure multiplication you need a stepped piston (change in diameter) between the air and liquid

aboard_epsilon
04-16-2009, 08:53 AM
PEOPLE ARE MISUNDERSTANDING THE QUESTION ..
I WANT 45 PSI LIQUID PRESSURE

i have at my disposal ...air pressure to 90 psi
a lathe and milling machine to make the vessel
materials to make the vesel ...why would i want to go out and buy a pump ?

there is no multiplcation going on ..according to marks answer ..he answered it ..unless others know different

all the best.markj

Willy
04-16-2009, 09:01 AM
You will get 45 psi out.
Dry gauge, wet gauge, it does not matter...pressure is pressure, it does not matter.
An air gauge will read hydraulic pressure and vice versa, all that matters is that the gauge has the right pressure range.

wierdscience
04-16-2009, 09:08 AM
Electric fuel pump from a car with a rail injection system(45-60psi) and a fuel pressure regulator with a tank return.This will allow pressurizing the fuel directly with out the need for air in an accumaltor at pressure.

Pressurized air and fuel in a sealed container is a bad idea,flaming death comes to mind.If you must build what you have drawn,please use CO2 or Argon and not compressed air.

digger_doug
04-16-2009, 09:12 AM
"PEOPLE ARE MISUNDERSTANDING THE QUESTION ..
I WANT 45 PSI LIQUID PRESSURE "

Stop shouting, we are trying to help you

"i have at my disposal ...air pressure to 90 psi
a lathe and milling machine to make the vessel
materials to make the vesel ...why would i want to go out and buy a pump ?"

Well now, because some of us have done these things before, and
the road your going down has problems. Problems we didn't
include in our post's.

Just like the litlle snippets of info you didn't include in your question.

aboard_epsilon
04-16-2009, 09:23 AM
Pressurized air and fuel in a sealed container is a bad idea,flaming death comes to mind.If you must build what you have drawn,please use CO2 or Argon and not compressed air.

OK will bang argon into it then ...
any hows, what do they use for propellant of aerosol cans containing ..wd40 ,paint , hair lacquer.
edit ...and come to think of it every spray gun ...im not talking hundreds of psi here ..that is needed to compress diesel to ignight ...and have said will not do it on petrol ..

and im with out any transport ...so cant go hunting around for fuel pumps .

all the best.markj

moe1942
04-16-2009, 09:23 AM
Pressure X area = force. Figure it out. Simple physics lifts heavy objects.

Circlip
04-16-2009, 09:34 AM
What most are alluding to but saying in different ways Mark is that when you do pressure "TESTS", Hydraulic is good, Air (or ANY gas) is bad. Much SAFER to have a liquid pressure system between the liquid and the "Nozzle" Yer can't compress a liquid, but you can a gas and therebye hangs the problem.

Regards Ian.

Mark McGrath
04-16-2009, 11:20 AM
Pressure X area = force. Figure it out. Simple physics lifts heavy objects.

This is very true but how does it relate to the current question?

oldtiffie
04-16-2009, 11:21 AM
Mark.

This may be a bit OT, but my car has dual fuel - Petrol (UK and OZ - "gas" in the US) and LPG.

My car starts on petrol and that switches off as I release the "start" on the ignition key when the engine starts and then it runs on LPG.

I asked my Mechanic about failure of the petrol system and he said that the car would start OK on LPG but it would be a bit harder - more so in Winter than Summer.

My older LPG system has the LPG delivered into the intake manifold on the engine side of the throttle disc and so is the same as a non-injected car (ie normally aspirated). The petrol is injected from the rail directly into the cylinders.

On my system the fuel system is on and running even when I am running on LPG.

If your petrol pump were to switch off with your "start" switch there should be minimal pressure in your fuel system and rail and injectors and so there will be minimal dripping.

I'd guess that if your injectors are dripping through wear that cleaning them won't cure them. But if they are leaking because of a contaminated fuel (petrol system, including the tank, pipes, rail etc.) then even if they are cleaned it won't be long before they are fouled and dripping again.

My point here is that if your car is anywhere similar to mine that at least you can use it until you find out what is really wrong and do something about it.

Its your call after all.

Weston Bye
04-16-2009, 11:39 AM
If all you want to do is test a few injectors to see if they leak, the setup you describe is completely sufficient, provided you do a reasonable job of welding up your pressure vessel.

I just finished a fixture for leak testing diesel locomotive injector coils at 1100 psi using 90 psi shop air. It involved using a 3" air cylinder to push a 3/4" hydraulic cylinder for pressure multiplication. The area under pressure is so small that the leaks, when they happen, aren't very exciting.

Speaking of pressure vessels, I once loaned a 1000 gallon steel tank to an idiot to use as a temporary water reservoir while he was doing some well work. Seems that the water wasn't draining out of the tank fast enough for the idiot so he hooked up his compressor to "force" the water out faster. The tank held up but was shaped like a football when I got it back. Idiot...

Circlip
04-16-2009, 11:45 AM
From yer sketch Mark, you're quite close to re-inventing a blowlamp. :D

aboard_epsilon
04-16-2009, 12:23 PM
Mark.

This may be a bit OT, but my car has dual fuel - Petrol (UK and OZ - "gas" in the US) and LPG.

My car starts on petrol and that switches off as I release the "start" on the ignition key when the engine starts and then it runs on LPG.

I asked my Mechanic about failure of the petrol system and he said that the car would start OK on LPG but it would be a bit harder - more so in Winter than Summer.

My older LPG system has the LPG delivered into the intake manifold on the engine side of the throttle disc and so is the same as a non-injected car (ie normally aspirated). The petrol is injected from the rail directly into the cylinders.

On my system the fuel system is on and running even when I am running on LPG.

If your petrol pump were to switch off with your "start" switch there should be minimal pressure in your fuel system and rail and injectors and so there will be minimal dripping.

I'd guess that if your injectors are dripping through wear that cleaning them won't cure them. But if they are leaking because of a contaminated fuel (petrol system, including the tank, pipes, rail etc.) then even if they are cleaned it won't be long before they are fouled and dripping again.

My point here is that if your car is anywhere similar to mine that at least you can use it until you find out what is really wrong and do something about it.

Its your call after all.

Yup exactly ..may have to disconnect the fuel pump to get it through the mot on LPG ..run it on petrol then 'till the pressure has gone
that i know ...

I noticed a while back that my exhaust analyser ...would shoot up to 4 percent on co randomly when engine was ticking over..........then when i seen a petrol wetted plug...after the car hadn't been started for three weeks ..my mind began to suspect that injector ..(first in line on the rail ) was at fault

i can start on LPG from dry without any petrol being involved ..just keep the LPG switch pressed in when i start .

i have this feeling ...that because it runs mainly on LPG ...that the injectors may have that creamy brown coloured scale in them, from drying out ...that you often see in a carb float bowl of an engine that hasn't been used for months ..eg ..lawn mowers, chainsaws and outboards.........i have a feeling that this may be hampering proper closing off of the injectors...then again i may be totally wrong.

I don't know ..anything about injectors ..but i believe these are "disk type injectors"

they have D3184GB written on them with a blue stripe around them ...and are rover part number MJY100460..........they also fit BMW mini turbo ...there are two in the mini four in mine.....

hell of a price at 96 plus vat !! EACH
worn out ..i don't know ...cars only done 84,000


warnings about fireballs ....like what do you think is in a spray gun ..they don't explode and some are in excess of 45 psi...white spirit will probably be my testing medium.

all the best.markj

wierdscience
04-16-2009, 09:01 PM
It sounds like you do have an injector stuck open.It could be fuel line smut,or it could be garden variety trash picked up at the local filling station.I'm leaning towards the lone piece of trash.If it were the tan goo then there should be more than one injector giving fault.I know the feeling buying injectors,new ones for my Ranger set me back $54/each x's 6:eek:

Fireballs,there isn't much chance of one,but adding pressurized air increases those chances.All it takes is a flash of static at the wrong time to cause problems.Maybe fill the tank nearly full and keep headspace to a minimum.

Rattle cans used to use CFC's for propellant,now it's down to propane,butane and co2 depending on product.

hardtail
04-16-2009, 09:14 PM
It sounds like you do have an injector stuck open.It could be fuel line smut,or it could be garden variety trash picked up at the local filling station.I'm leaning towards the lone piece of trash.If it were the tan goo then there should be more than one injector giving fault.I know the feeling buying injectors,new ones for my Ranger set me back $54/each x's 6:eek:

Fireballs,there isn't much chance of one,but adding pressurized air increases those chances.All it takes is a flash of static at the wrong time to cause problems.Maybe fill the tank nearly full and keep headspace to a minimum.

Rattle cans used to use CFC's for propellant,now it's down to propane,butane and co2 depending on product.

The old 7.3 Navistar injectors were running $400 a pop up here in their day, for $3200 most just dug a lil deeper and got a full rebuilt w/ injectors.......

davidfe
04-16-2009, 09:58 PM
http://www.jalopyjournal.com/forum/showthread.php?t=318385&highlight=injector+cleaning

Jason has a thread above that is recent and deals with ultra sonic
cleaning.

He is a good guy and will help.

Good luck.

wierdscience
04-16-2009, 10:00 PM
The old 7.3 Navistar injectors were running $400 a pop up here in their day, for $3200 most just dug a lil deeper and got a full rebuilt w/ injectors.......

Same here,guys were buying ex-county school buses at auction for $1,200 for the engine for that reason.

oldtiffie
04-16-2009, 11:18 PM
Yup exactly ..may have to disconnect the fuel pump to get it through the mot on LPG ..run it on petrol then 'till the pressure has gone
that i know ...

I noticed a while back that my exhaust analyser ...would shoot up to 4 percent on co randomly when engine was ticking over..........then when i seen a petrol wetted plug...after the car hadn't been started for three weeks ..my mind began to suspect that injector ..(first in line on the rail ) was at fault

i can start on LPG from dry without any petrol being involved ..just keep the LPG switch pressed in when i start .

i have this feeling ...that because it runs mainly on LPG ...that the injectors may have that creamy brown coloured scale in them, from drying out ...that you often see in a carb float bowl of an engine that hasn't been used for months ..eg ..lawn mowers, chainsaws and outboards.........i have a feeling that this may be hampering proper closing off of the injectors...then again i may be totally wrong.

I don't know ..anything about injectors ..but i believe these are "disk type injectors"
....................................
...................................


all the best.markj

Mark,

I was advised by my Mechanic to use an upper-cylinder (and other related parts - including injectors - 1ml/litre) lubricant (formulated for LPG/dual-fuel engines) in the petrol and to run the car on petrol for 50+KM (30 miles) at least once a month - which I do - and so far (200,000KM ~ 120,000 miles) I have not had any problems at all - not even an injector clean. He also advised against service/petrol stations in cheap/discount fuel arrangements with large super-market chains as the (here) "AU$0.04/litre off" is false economy in many cases as he had had a lot of repairs in with that problem (including contaminated petrol.LPG) the costs of which ate up an awful lot of "4 cents per litre savings". I took that advice too. No problems.

I had an engine change at about 300,000 KM but use the original injectors.

Sometimes "cheap fuel" is not unlike some cheap deals on eBay!!

One of the big advantages of dual fuel is that if you have a fuel failure or run out of fuel in one fuel you can instantly change fuel and get going. I had a petrol pump failure just after I bought it but was with a couple of hundred meters from the trader I bought it from - so it went straight to his garage and a new pump was shipped there and then - it was under warranty - and that rather than cost-savings was the main reason I had the LPG system fitted. I have never regretted it.

My fuel cost in terms of $/KM is about half on LPG as to that on petrol so the LPG system has well and truly paid for itself a long time ago.

Thruthefence
04-16-2009, 11:28 PM
I am an aircraft mechanic by trade, and back in the day before there were so many specialist shops around, we would field clean & test Pratt & Whitney PT-6 turbine engine fuel nozzles with a rig very close to what you have sketched. While the injectors themselves are 'apples & oranges' the process sounds similar. We ran nitrogen as the pressurizing gas, at 100 psig. The nozzles were checked for the proper cone pattern, lack of streaking, clean shut off(no dribbling allowed) and as the pressure is reduced ( using a simple regulator) an symmetrical "onion" shape was supposed to appear at the nozzle tip. This was done to the nozzles at 400 hr intervals. The fuel passes through the nozzles was JP4, really just highly refined kerosene, and having done this, and having seen it done scores of times, I have never seen a fire, or a ruptured vessel. Fortune favors the prepared, of course, so no smoking, or doing this in an enclosed area. There are processes now where the nozzles can be cleaned in sitsu, by pulsing a high pressure cleaner thru them. Mostly, they are removed and sent in to a shop that specializes in turbine engine work for cleaning, or you simply install an "exchange" set. If your nozzles are to be actuated electrically, be sure & match impedance, or you'll burn out the coils, and watch out for sparks!!

moe1942
04-17-2009, 08:36 AM
This is very true but how does it relate to the current question?


Mark if you exert 45 PSI on a liquid in the pressure chamber figure out how much area it is and multiply by 45 PSI and that will be the resulting pressure. Do a search on hydraulics and it will become clear.

Just from your drawing with no dimensions I would say that the final pressure would be much greater than 45 PSI.

What I would suggest is to use something like a port-a-power with an in line gauge. Just pump til you get the desired pressure on the injector and see if it leaks.

aboard_epsilon
04-17-2009, 09:51 AM
Mark if you exert 45 PSI on a liquid in the pressure chamber figure out how much area it is and multiply by 45 PSI and that will be the resulting pressure. Do a search on hydraulics and it will become clear.

Just from your drawing with no dimensions I would say that the final pressure would be much greater than 45 PSI.

What I would suggest is to use something like a port-a-power with an in line gauge. Just pump til you get the desired pressure on the injector and see if it leaks.

yes

That's what i was thinking when i originally asked the question ..and why i used the word hydraulic
however people with much more mental capacity than me, have said it would be exactly the same pressure coming out as going in ...
you're the only doubter .

if there was a sealed metal disk over the liquid then your case would stand the point ..

with it being air over liquid ...something else happens

no doubt ...others will contribute ...

the more that say it will be the same ...the more I'm inclined to believe it

all the best.markj

Mark McGrath
04-17-2009, 10:23 AM
Mark,
consider the air receiver on your compressor.If the gauge shows 45psi in the receiver,to what pressure can you blow up a tyre?
Scots Mark.

Barrington
04-17-2009, 12:15 PM
Mark if you exert 45 PSI on a liquid in the pressure chamber figure out how much area it is and multiply by 45 PSI and that will be the resulting pressure. Do a search on hydraulics and it will become clear.

Just from your drawing with no dimensions I would say that the final pressure would be much greater than 45 PSI.

No, this is not correct. I'm afraid you are confusing pressure and force.

Say for example the area of the surface of the liquid is 10 sq ins. The total force pressing down on the liquid is then 45 x 10 = 450 lbs.

However this force is applied to the liquid over the same area of 10 sq ins so the pressure in the liquid is 450 / 10 = 45 lbs per sq in.

It would be exactly the same if there were a freely moving piston between the air and the liquid. The 450 lbs applied to the top of the piston by the air pressure acts on the 10 sq ins of liquid under the piston to create a pressure of 45 psi in the liquid.

Cheers

aboard_epsilon
04-17-2009, 01:23 PM
No, this is not correct. I'm afraid you are confusing pressure and force.

Say for example the area of the surface of the liquid is 10 sq ins. The total force pressing down on the liquid is then 45 x 10 = 450 lbs.

However this force is applied to the liquid over the same area of 10 sq ins so the pressure in the liquid is 450 / 10 = 45 lbs per sq in.

It would be exactly the same if there were a freely moving piston between the air and the liquid. The 450 lbs applied to the top of the piston by the air pressure acts on the 10 sq ins of liquid under the piston to create a pressure of 45 psi in the liquid.

Cheers

weather he's saying it the wrong way round or not ..

is not the argument .

from what youre saying ..my 45 psi over the liquid of an area of 10 sq ins
..is now going to become 4.5 psi .. ????

where as others have said ...45 psi in...45 psi out .

so who is right and who is wrong ?

all the best.markj

Barrington
04-17-2009, 02:04 PM
from what youre saying ..my 45 psi over the liquid of an area of 10 sq ins
..is now going to become 4.5 psi .. ????

I'm certainly not saying that - where on earth did that come from ?? !!!

Again:-

Pressure (psi) = Force (in lbs) / Area (sq.ins) i.e. lbs PER sq in

so Force (lbs) = Pressure (psi) x Area (sq.ins)

The air pressure is producing a force against the surface of the liquid.

This force is found by multiplying the pressure by the area.

45 psi acting on an area of 10 square inches produces a force of 450 pounds

BUT the force of 450lbs is spread over the area of 10 sq ins of liquid so the pressure in the liquid is 450 / 10 = 45 psi

The pressure in the liquid is the same as the pressure of the air above.

I'm sorry to have confused you - I was attempting to explain why the fact that one fluid was air and the other was liquid was not significant...

Willy
04-17-2009, 02:35 PM
Barrington is correct in his explanation of hydraulic theory as it relates to your pressure vessel.

If you multiply the 45 psi by the number of square inches inside of your pressure vessel you will have the total amount of force applied to the vessel. This figure rises quickly, either due to the number of square inches or the amount of pressure involved. This is why pressure vessels are heavily constructed...the forces are large.

Think about it this way...twenty psi will easily support an automobile that weighs 5000 lbs., the bigger the tire the less psi required because there is more surface area for the air pressure to work on.

So in your example 45 psi in = 45 psi out. The size of the vessel determines how much force it must contain.

Willy
04-17-2009, 02:49 PM
Mark if you exert 45 PSI on a liquid in the pressure chamber figure out how much area it is and multiply by 45 PSI and that will be the resulting pressure. Do a search on hydraulics and it will become clear.

Just from your drawing with no dimensions I would say that the final pressure would be much greater than 45 PSI.



Moe, think about the term psi, pounds per square inch. The pressure that is applied to the container and the liquid inside of it is 45 psi...how could the pressure intensify?
Only the amount of force on the container would increase if the container were enlarged.

aboard_epsilon
04-17-2009, 02:52 PM
BUT the force of 450lbs is spread over the area of 10 sq ins of liquid so the pressure in the liquid is 450 / 10 = 45 psi

ok but...it takes some very carefull reading of it ..to understand :)

all the best.mark

Norman Atkinson
04-17-2009, 03:23 PM
MarkJ,
less than 18 months ago( November), I was in HongKong.
They have or had 18000 taxi cabs running on LPG and carrying a million people per day. All the cars are Toyotas and despite the dated design, are being replaced like for like.

So the technology is there and well understood and well established.

So what is the problem?

Norm

John Stevenson
04-17-2009, 03:55 PM
He doesn't live in Hong Kong.

.

Willy
04-17-2009, 04:14 PM
He doesn't live in Hong Kong.

.

No.
He's driving (read...working on) a Rover.:D

Jeffw5555
04-17-2009, 04:23 PM
Pressurized air and fuel in a sealed container is a bad idea,flaming death comes to mind.If you must build what you have drawn,please use CO2 or Argon and not compressed air.

Nonsense. Danger is only present at or near stoichiometric ratios of fuel to air, which is impossible as the air will absorb a much higher ratio of fuel vapor in this situation.

Plus you need a source of ignition, and I don't see any spark plugs or other ignition devices in his drawing.......

The only danger comes from the vessel rupturing under pressure, or a leak from the outlet on, which he will not be able to shut off easily until the air pressure has subsided. This can easily be rectified by putting a shutoff valve on the outlet....

This group often exaggerates danger of fairly safe situations.....

Norman Atkinson
04-17-2009, 05:10 PM
But John, the British Government are going to give 3000 for each Rover- dead and alive.

We may have a millionaire waiting in the wings.

N

John Stevenson
04-17-2009, 05:39 PM
It's 2,000 and only if you buy a brand new car.
It's not been announced yet but I'll bet it's on a sliding scale. They won't give two grand against a six grand Fiat and two grand against a thirty grand Land Rover.

I'll bet the fiat guy gets eighteen shillings and sixpence and the two grand is only applicable on certain models.

Anyway none of this sorts Marks problems out.
He's trying to sort out his only affordable ride and I dare say he doesn't have much choice about replacing his vehicle the way things are.

You in next week Norman ? Got to do a new machine installation and a half days training at Morpeth, that's near you innit ?

.

pressurerelief
04-17-2009, 05:52 PM
Jeffw5555,

"Plus you need a source of ignition, and I don't see any spark plugs or other ignition devices in his drawing......." Your ignition source is static electricity.

In the US the pressurizing of a flammable liquid in a DOT vessel (cylinder, cargo tanker, truck, etc) is prohibited by law because of the danger of fire. At some point the flammable mixture is just right as you go through the flammmable range. If you build it yourself you can do whatever you have the brass one's to do, but the Darwin Awards are coming up too. I know he is in Europe but the logic is the same.

If you change the fuel from Petrol to a combustible fuel such as kero the risk goes down exponentially.

P/R

aboard_epsilon
04-17-2009, 06:29 PM
When i used to work down the mines ..
they had air hoists that regularly seized ..
the cure was to put diesel in the airline ...

this resulted in smoke coming out of the exhaust ..not vapour ..
defo smoke ..

and me .............i wasn't there for long ..

i was gone ...in another road ..in another part of the mine .

despite my protests, they still did it ..

It wouldn't have been a problem to me ...out in the open .......but in a confined place like that ...and the most gaseous mine in the country..it was my nerves.... couldn't take it .

so............DARWIN WONT GET ME UNAWARES .

all experiments with this device will be done outside !!!

all the best.markj

Jeffw5555
04-17-2009, 06:46 PM
Jeffw5555,

"Plus you need a source of ignition, and I don't see any spark plugs or other ignition devices in his drawing......." Your ignition source is static electricity.

In the US the pressurizing of a flammable liquid in a DOT vessel (cylinder, cargo tanker, truck, etc) is prohibited by law because of the danger of fire. At some point the flammable mixture is just right as you go through the flammmable range. If you build it yourself you can do whatever you have the brass one's to do, but the Darwin Awards are coming up too. I know he is in Europe but the logic is the same.

If you change the fuel from Petrol to a combustible fuel such as kero the risk goes down exponentially.

P/R
Again, nonsense.

Static electricity applied to the OP's question is not probable inside the vessel, and I revert back my origninal point that a near stoich mixture will not exist in the vessel.

Your point about DOT rules for flammable transport is non-relevant.

aboard_epsilon
04-17-2009, 07:18 PM
It's 2,000 and only if you buy a brand new car.
It's not been announced yet but I'll bet it's on a sliding scale. They won't give two grand against a six grand Fiat and two grand against a thirty grand Land Rover.

I'll bet the fiat guy gets eighteen shillings and sixpence and the two grand is only applicable on certain models.

Anyway none of this sorts Marks problems out.
He's trying to sort out his only affordable ride and I dare say he doesn't have much choice about replacing his vehicle the way things are.

You in next week Norman ? Got to do a new machine installation and a half days training at Morpeth, that's near you innit ?

.
bugger the new fangled crap .....had enough of this one ..

new car ......these are hybrids they are on about .......

the new Honda 15,000..........100,000 mile 8 year warranty....as long as you have it serviced by them ...at 400 a time.........because its a hybrid ...you get it for 10,000

after eight years its worth 2000

so 1000 pound a year in depreciation and another, perhaps another 4000 to Honda for servicing it....some years two sevices will be needed...hmmmmmmmm don't sound like a good deal to me...............my car is trouble i know .but it ain't 1500 pounds a year of trouble.

all the best.mark

John Stevenson
04-17-2009, 08:18 PM
Too right, I have the figures for the car and van in front of me.
Not counting diesel, tax or insurance in the last two years the car has had one service which was done here and consisted of oil change and 3 filters. It's also had two wiper blades and a set of heater plugs.

The van has had 2 services, again oil and 3 filters, two wiper blades, one exhaust rubber and a front brake pipe.
53 pounds total for the car and 65 for the van, that's two years running.

If we move up on both vehicles they will have to go to a dealers because of the computerised servicing and they will no longer have mechanical injection but computerised electronic injection.

The scrappies Volvo truck had a miss fire and it was diagnosed faulty injectors, 6 injectors later at 650 each and it still had the miss fire :mad:

aboard_epsilon
04-17-2009, 09:18 PM
Looks like my lpg injectors have had it too

proper cure is a new 180 injector rail...at 14,000 miles only

this is a fecking joke !!!

all the best.markj

jb-mck
04-17-2009, 09:35 PM
Regarding the aerosol question, WD-40 uses compressed CO2. Most others use blends of Propane and butanes. If you tried to use the LPG, say propane, it will simply blend with the other hydrocarbons.

oldtiffie
04-17-2009, 10:07 PM
Looks like my lpg injectors have had it too

proper cure is a new 180 injector rail...at 14,000 miles only

this is a fecking joke !!!

all the best.markj

Injectors? What injectors?

As I said, my system - old technology - which has no LPG injectors - and which just passes LPG from the regulator/control to the intake manifold venturi (just after the throttle disk) is "normally" aspirated, but "petrol" is injected as normal (that is very reliable as well).

It may lack a bit of "high/er tech" and perhaps be a bit less efficient but its been pretty well "bullet-proof" to date to the extent that any real or perceived "savings" had I upgraded would have been swallowed by repairs such as yours.

I have the gas (LPG) and petrol systems "tuned" each time the car goes in for service. Its just another "line item" while its in there - about every 6 months - depending on service intervals and "mileage" traveled. The car also goes to the "Panel shop" every 2 years to have any "dings" and rust etc. taken out and anything else that needs doing.

Did I mention that my 6 cylinder 3.9 litre car is a 1989 "Ford" with an Italian LPG "set"?

With a bit of luck, that car is good for another 5 years.

Parts are readily available and a damn side cheaper than a lot of "later" and more "modern" or "exotic" car part are. A service or tyre-change on some of them costs more than my car or a reasonable replacement costs (or is worth).

I am not too sure how much "savings" and "efficiency" I can afford - or need.

Best of luck with the LPG.

aboard_epsilon
04-17-2009, 10:22 PM
yeah had the old tech LPG on my last car ..
vap and mixer

was reliable did more mpg out of an ancient two valve engine and heavier car.

only downer was the car was slower in acceleration ..and lacked top end ..

now I'm a bit older i can put up with that ..

i was told because this car had ecu and 02 sensor that i had to have this new fangled crap on it ...and lapped it up like a soft bugger .

the car performs ..or did perform the same as on petrol .

but down on the fuel consumption ..
the injector system compensates for the slow sluggish attributes of the old system by injecting more gas .

think i would rather have a slow car ...that uses less fuel .

you live and learn .

Italian **** reliability ..who are they trying to kid

http://www.youtube.com/watch?v=npaW-2Q2AGc&eurl=http%3A%2F%2Fvideo%2Egoogle%2Eco%2Euk%2Fvideo search%3Fq%3Domvl%26emb%3D0%26aq%3D%2D1%26oq%3D&feature=player_embedded

all the best.markj

moe1942
04-18-2009, 11:47 AM
yes

That's what i was thinking when i originally asked the question ..and why i used the word hydraulic
however people with much more mental capacity than me, have said it would be exactly the same pressure coming out as going in ...
you're the only doubter .

if there was a sealed metal disk over the liquid then your case would stand the point ..

with it being air over liquid ...something else happens

no doubt ...others will contribute ...

the more that say it will be the same ...the more I'm inclined to believe it

all the best.markj




Mark find Pascals Law and it will become clear. Air over hydraulic is called pneudraulics and same principle applies.

aboard_epsilon
04-18-2009, 12:05 PM
Thats the least of my problems at this mo

I've only done 15,000 and i think one of my LPG injectors are faulty ..

it runs on petrol OK ...very lumpy on LPG

I've checked the plug leads ...OK
changed the coil ..

all LPG filters are spotless.like brand new...both the liquid one on top of the vap
and the vapour one

there is a lot of noise coming from the LPG injectors ..even when hot

The first three injectors on the rail ..when i pull the injector-wiring-plug on each one ...it makes a difference ..
the 4th feeding cylinder four ...hardly any difference at all ...the engine even
sounds happier to run without this one .........and that's the LPG injector that is making the most racket .

I do know, I have a weeping petrol injector on four .........but Ive taken this out of the equation by pulling the inertia switch plug ...so stopping the petrol pump ..and manually releasing the pressure by undoing union on petrol line....so releasing pressure out of the petrol rail,...and starting on LPG only..still the same

So my main goal now is to get the thing happy on LPG .

there are LPG OMVL dream 21 overhaul kits on ebay ..ive posted in other LPG forums ..asking if they are any good ..and I'm still awaiting answers.

omvl dream 21 is the name of the LPG system.

all the best.markj

Tobias-B
04-18-2009, 09:26 PM
That drawing looks a lot like an 'Accusump' minus the discriminator piston.

As made by Canton- Mecca for providing a backup source of
oil pressure to race car engines in high- g corners...

http://www.accusump.com/

...but they're real money...

t

Thruthefence
04-18-2009, 09:42 PM
Or a hydraulic accumulator from an aircraft. Long tube, piston floats in tube, Hydraulic fluid on one side of the piston, nitrogen on the other. Used to provide a sort of 'emergency' shot of hydraulic pressure, should you lose a pump.

moe1942
04-19-2009, 10:07 AM
Or a hydraulic accumulator from an aircraft. Long tube, piston floats in tube, Hydraulic fluid on one side of the piston, nitrogen on the other. Used to provide a sort of 'emergency' shot of hydraulic pressure, should you lose a pump.

Make Great preoilers on vehicles. Prevents dry starts.

aboard_epsilon
04-19-2009, 04:52 PM
I was sure this guy posted here ..
but he didnt

he posted in the other forum

lots of good stuff

http://www.practicalmachinist.com/vb/showthread.php?t=158732&highlight=injectors+escort

well bad lpg injectors ..and bad petrol injectors ..i done a test on it today ....only CO with my snap-on gas analizer

0.2 percent on lpg ... mot limit 3 percent..
0.1 percent on petrol...mot limit 0.2 percent

they are both passes for CO

we will see how the other gases perform tommorow ..in the MOT

all the best.markj