Only thing is, at higher rpm in neutral the engine manifold pressure will be lower than at normal idle speed, and since gas pressure is relative to manifold pressure gas pressure should be lower at high idle speed so less gas should escape from any leak.
Yeh that's good!
Must have been quite a leak on the 4mm pipe. Even without a spring clip or even if you cut part way through that pipe would still expect the pressure sensor to read system pressure.
Simon
As said, a bit of a leak (hiss when you bend pipes etc) on the 4mm pipe between Matrix and pressure sensor is unlikely to be enough to cause a low pressure reading at the sensor. But you'll want to eventually fix this problem anyway and it would be a good idea to fix it now so you can at least rule this out.
Whilst on the subject of the errors page - The software may show an errors page but we don't yet know if your ECU/firmware are new enough to support error reporting. But it's worth checking to see if any faults register for gas vapour temp sensor... If the ECU picks up on such error it will switch back to petrol anyway.
Recap...
You have ruled out some potential causes such as blocked liquid filter and solenoid. It is very unlikely that the tank pickup pipe has come off, far more likely that there's a problem at the front end such as faulty reducer. The leak(s) as you described them seem to be inconsequential.
Simon
I think it's unlikely that this leak will be cause of the system reading low gas pressure - If the leak was bad enough to have sensor read low gas pressure you'd certainly have known about it before. Also, any leak that you can start and stop by moving pipes probably equates to only a small fraction of the gas that the engine could use if you put your foot down.... so although it might hiss and stink and generally be less than safe, such leak is probably negligible in terms of a proper functioning reducer's flow capability. The one exception would be if you pulled the pressure pipe to the pressure sensor just about all the way off but then you'd smell and hear it.
With the front solenoid guts removed there's still the tank solenoid, so if you create a leak on the vapour side gas will leak for quite a while (until liquid gas between tank and reducer is used up) before dying down.
You can't use petrol hose for LPG.
5mm or 6mm internal diameter pipe between injectors and manifold, 4mm internal pipe between Matrix injectors and pressure sensor.
Simon
super4 wrote:
Have checked wiring and things I can get to, managed to get 12 volts to the solenoid on the reducer which sort of worked but did not seem as active as the one on the tank - it may be that the connection I was making was not very good. But what I want to ask is - does the pressure come from the simple fact that the gas in tank is under pressure and therefore makes its way to the intake manifold provided solenoids etc allow it or does the pressure get built by the reducer in addition. If the pressure is in the system all through then presumably I have a blockage or as suggested, a solenoid simply not opening ? Is it as simple as that ?
The tank solenoid will likely be a lot louder than the front solenoid because it is on the tank.. Tap the tank with a screwdriver and it will make a lot louder noise than if you tap the front solenoid with a screwdriver. Plungers in solenoid posts do get fouled with crud / heavy ends but if they open at all they usually flow enough to allow the engine to run OK and it's a similar story with filters. But you could rule out both the plunger and the filter by simply removing them temporarily to see if the same happens with them removed. Even if removing them seems to effect a cure (which might point to plunger post or filter problem) the real problem could still be voltage drop when the injectors pulse for longer duration (could still be main power feed issue).
Simon
Orangebean wrote:
Handy hint, not LPG related, but...
Wheels stuck on hubs- loosen wheel nuts (sufficient to allow wheel to wobble on hub but not fall off). Drive car forwards and backwards a bit while turning steering from lock to lock.
Most of the time just loosening nuts and turning steering from lock to lock will do it.
Much easier on the back!
In my boy racer days I followed a group of lads who were in a mk1 Escort down the A1 at 100mph, they pulled up due to steering wheel wobble, turned out they'd changed a wheel earlier but can't have done the nuts up properly because 3 nuts were missing and the one remaining was nearly at the end of its threads!
Sorry I missed this thread until now.
Unlikely to be a case of solenoid not opening enough to allow enough flow of liquid gas for idle but not enough flow of liquid gas for blipping the throttle or light acceleration... Unless the electrical feed to the solenoid is intermittent, in which case the solenoid might close when the throttle is blipped or in light acceleration - but unless this was due to a main power feed problem (to the LPG ECU) it would more likely be due to coincidence.
I have known plenty Zavoli reducers fail in a way where the maximum gas flow is severely restricted, in some cases the restricted gas flow has been enough to maintain vapour pressure for idle but for no greater load than idle... so blipping the throttle or light acceleration would cause pressure to fall away very quickly (can't maintain pressure of volume throughput is restricted, so pressure falls away, system senses lack of pressure and switches back to petrol). The situation described here would call for a new reducer but this may not be the case and it's worth doing other checks first.
The gas vapour temp sensor will need fixing, it's worth checking the solenoids and for issues such as bad main power feed / earth.
You could monitor voltage to the solenoid(s) while switching to gas, at idle on gas, and when you blip the throttle. The injectors pulse for longer with higher engine loads (such as when blipping the throttle) soif there's a bad main power feed to the LPG ECU the extra current drawn can cause voltage to all LPG components to lower which could cause solenoids to close or sensors (including pressure sensor) to read incorrectly.
After the system has beeped and switched itself back to petrol you could read vapour pressure on screen again, N/A (not applicable) means no pressure... If you do a pinch test on a vapour pipe (or disconnect a pipe) you'll know if this seems to be a true or false reading. False reading points to pressure sensor, voltage or ECU problem. True reading points to solenoid, voltage or reducer problem.
Another thing about Zavoli reducers is that they only really like to work at the pressure for which they were designed (1.2 or 1.5 bar depending on model). Like other reducers they have a pressure adjusting screw but on Zavoli reducers if you turn pressure down they tend not to be capable of flowing nearly as much gas (throughput) as at standard pressure.
This is all assuming the feed from the tank is good - If the tank were outputting vapour instead of liquid (on a single hole tank, particularly 30 degree tanks) if the flexible pipe that picks up liquid from the bottom of the tank has come off inside the tank the tank will output vapour. The reducer needs to be fed liquid gas but might flow enough for idle if fed vapour.
Simon
Yesterday I removed a complete LPG system from a Disco3 with Jag engine.
System comprises 95L 4 hole full toroidal tank (was underslung), Agis electronics and injectors, KME reducer, BRC style forced lube system.
The owner will be selling the lot, probably on Ebay.
He said he doesn't much like LPG anyway, and besides, Guy Salmom (his preferred Landrover dealers) won't have the vehicle in their shop with the LPG system installed, not even just to service it. I did mention he could have taken it to one of the many other LR specialists but he wanted it removing and had me spell out very specifically on his receipt that all of the LPG system was removed to appease Guy Salmom!
The tank was a pita to remove, bolts all seized and difficult to access... angle grinder job! Cut the rear bolts easily but couldn't get to the front bolts until I'd slipped a jack in between the tank and Disco underframe to pry the tank down a bit, even then I had to put a 9" cutting wheel on a 6" grinder to reach a front bolt... the big disk spinning so close to my hand in a hard to reach spot wasn't something I enjoyed! With only 1 bolt remaining I fatigued it off rather than repeat the risky cutting.
The bits would fit and work on other LR models including P38s but the front end bits would be a bit difficult to get spare parts for, The 4 hole tank will be the most valuable and useful part here but will need a bit of work - new solenoid post, coil, will come without a filler or JIC filling pipe, I'd advise a new level sender, it'll need wire brushing and paint.
If anyone contacts the seller don't mention this post ;-)
Simon
As Gilbert said.
The 4 hole design can also be mounted internally or externally.
The advantages of the Icom and zero degree design over 4 holes are that they don't have that big box on the side so you might keep your jack storage etc,.. and the flat valve base on 4 holes can mean you lose a couple of litres capacity compared to a 0deg tank of same dimensions, though not usually in 720x270 tanks.
Not that I'd be concerned but all internal pipes should run inside external venting.
Simon
Bigas was a surprise to me, most often where I've seen Icom tanks fitted on aftermarket installs the front end components are a bit unusual too (e.g. AG / Voltran / etc), there's nothing unusual about Bigas.
You'll probably need to change or at least fix the tank valve, would start by looking under the tank's gas tight housing cover to see what type of valve(s) it has, Icom tanks with this type of gas tight housing may have one of a few different types of valve setups. Your type of tank has it's advantages over single hole and 4 hole tanks, I could think of a few applications where they'd be ideally suited but I'd like them more if parts were more easily available.
It is possible to safely fit a normal 95L zero degree (external) tank in the wheel well of a P38. The old way of doing this was to have the valve protrude through the side of the spare wheel well at about 315 degrees (too far North and the anti-roll bar will catch it, too far West and the valve won't reach the tank from the outside of the wheel well due to the squared off bit of well where the jack etc fit)but it's a lot of extra work for the extra few litres the full toroidal external tank offers over the 30 degree internal tank of same measurements because not only does the valve have to go through the side of the well in the correct position but also brackets have to be made to secure the tank from it's top (which is where an external tank's mounting lugs usually all are... there are exceptions, but suppliers don't tend to know which of their external tanks have lugs at both the top and bottom). Internal tanks are secured with a couple of bolts straight through the middle of the boot floor. In case you ever decided to change tanks rather than fix yours, these days it would be possible to fit an external tank upside down in the wheel well using a flexible valve cover, with the tank upside down it's mounting lugs could then be bolted through the well floor saving work making brackets and work fitting the valve, this type of setup would also allow you to keep with much of your existing piping. But an internal 30deg toroidal wlll hold just as much gas if it's valve is bent a bit, is much easier to fit and costs less.
This valving arrangement by Icom is unusual on aftermarket conversions but many are fitted on factory converted vehicles.
They're a pain when they go wrong and it seems yours might have gone wrong. If the problem is only at the tank end then it's likely the float is sometimes sticking or the fill shut off sometimes doesn't work. Or one (or both) of those issues could be constant, in which case the reason you don't always get 95L in it would be because you don't always run the tank empty, maybe because of a problem with the under bonnet components.
Obviously something went wrong at the tank end when you managed to get 95L in it, so, perhaps different subject - do you know what parts are fitted under the bonnet?
Simon
blueplasticsoulman wrote:
I used a 9v square battery and just did short clicks.
Yeh, I wrote in case anyone else tests injectors, some might not realise and just connect injectors to a fuel pump and battery for a while when checking spray pattern etc.
Thought I'd better write this, just in case...
Be careful not to apply power to petrol injectors for too long if testing them with a battery. The ECU employs 'peak and hold' current to control injectors,i.e. the injectors might get 1ms of near 12v to provide fairly high current to get them to open but then a much lower current to keep them open. It doesn't take long to break an injector if powered by a constant high current (and given the inhumanly short timescales injectors pulse for, even a second or so is some ways like constant to an injector). Only connect power to test for a split second and leave plenty time between tests to prevent the test becoming the cause of a new problem. I've known injector coils get burned out during such tests and I've known a previously fully working injector to become stuck open even when it's coil hasn't been damaged when such tests have been done to check spray pattern.
Simon
blueplasticsoulman wrote:
With manifold off, you can't see if an injector is leaking. You'll need to remove the whole fuel rail and injector assembly. Take each injector one by one and test. 2 of mine were letting fluid through before the battery was clicked on. I could even blow through them which means they were stuck open and leaking petrol in even when on lpg.
I really blasted the dodgy injectors with carb cleaner and let them sit for a few minutes. Then I clicked them on and off whilst spraying more cleaner through the rig. Got them freed off and they stopped letting fluid through when closed and I couldn't blow through anymore either. You'll see when it's clean cause it will spray through like a mist rather than like water through a shower head.
"I've fixed it" means I have indeed fixed it. (I hope) lol. I did coils, leads and spark plugs too. Reason being, I was on a mission to cure the fault so I just bought everything that it could possibly be. Didn't need the rest of the stuff as it turned out to be duff injectors but I fitted the rest of the gear anyway since i'd already bought it. Spark plugs had seen better days so i'm pleased I did them.
I've been off over the weekend due to my daughter's wedding so have just caught up... Nice one Chris, so we were right about leaky injectors!
Simon
Ferryman wrote:
I cleaned my block before relining at a manual carwash (on a not so crowded hour). Hot + shampoo, flush with hot water. I skipped the wax program.
Near here there's a 4x4 off-roading course (formerly Frickley pit tip) frequented by lots of 4x4s on a Sunday, all of which get very sludged up. Some local garages don't allow scruffy 4x4's to use the jetwash on a Sunday but a woman behind the counter at one of them (just an employee but a 'difficult' type even in the opinion of her workmates) is over vigilant and personally gives any tall vehicle the once over before she will sell a jetwash token even midweek. So seeing me pull up in a people carrier and get out with boots and scruffy workclothes on she gave my car the once over but sold me a token. Then I proceeded to jetwash the gunk from around the solenoid pack on my gearbox, gearbox sump and engine sump.
Hmm, diesel - also called detergent oil...;-).
I might have pushed the boat out a bit and turned up myself, no P38 but would be good to meet some old and new faces. Better not miss my daughter's wedding though!
Not long before around 10 years ago most AEB systems didn't feature sequential changeover, also instead of taking petrol injector pulse readings on every channel they would only take readings from the blue wires (front cylinder on each bank) and then the rear 3 cylinders on each bank would all get the same pulse duration as the front cylinder (except for any adjustments due to acceleration enrichment, which was calculated by the LPG ECU).. So an older install could have red / green / yellow wires all mixed up with no consequence on how the vehicle ran on LPG but if a newer ECU was later fitted in place of the old ECU (using same wiring) then the LPG injector pulses wouldn't match at least the order of petrol injection pulses, usually affecting at least smooth idle.
Is the 2.5ms at idle measured when running on petrol or gas? Does it stay the same when you switch fuels? What is ginj when pinj is at 2.5ms? If you drive flat out on petrol, what is the maximum pinj?
Simon
Lambda sensor setting in LPG software won't make any difference to autocal, as said earlier the only reason for the connection at all is to allow the installer to see lambda voltages on screen multimeter fashion, the LPG system doesn't take any notice of lambda readings other than displaying them on screen.
Biagotti Fast is the injector setting you want.
Unless your engine is running closed loop autocal has no chance of succeeding.
You also need to have injector routing correct, i.e.each LPG injector sends fuel to the engine cylinder that it should, so if your LPG petrol injector wiring is blue red green yellow respectively for cylinders 1357 the LPG injectors that fuel those cylinders should be ABCD respectively.
Set overlap to zero... Though stumble on changeover is most often due to incorrect routing and/or LPG calibration - If routing is incorrect and changeover is sequential (thus switches each cylinder separately a brief time apart) then when it turns off petrol to a cylinder and is supposed to start sending gas to that cylinder, what happens is that cylinder gets no fuel at all but another cylinder gets both petrol and gas, result is a misfire on 2 cylinders which will occur at least twice during changeover, and this is if routing on 2 cylinders is mixed up (the minimum possible besides no mix up) , it will be worse if routing is more mixed up than just 2 cylinders. Even with sequential changeover set, the engine can run OK with some mixups with routing, because when switchover is complete all petrol injection is off and all cylinders run on LPG. Depending on ECU firmware version and software the software may have facility to aid checking routing. Incorrect routing would also mess up autocal.
Which version of software are you running? Did you 'Reset the ECU' before running autocal? Did you adjust the pressure setting? When fully warmed up and idling nicely on petrol, what pinj readings are you getting?
Instead of running Autocal, try unticking the 'sequential changeover' box for now and setting all numbers in the map to 140.
Simon
Locks might otherwise be useful for practising jumps? Similar speed limit to rivers... I've skied up the Ouse a long time ago, fishermen wave and you wave back lol...
I still need to pull my finger out and see if I can fix my old speedboat's 3cyl Mercury 70hp 2 stroke engine circa 1982. I rebuilt the powerhead, rebore and new pistons (a pain because the cyl head isn't removable so pistons go in from the crank end and the design is such they're all supposed to go in at the same time while attached to the crank - without the special tool I managed 2 at the same time attached to the crank then attached the 3rd bottom end with the crank just off the main bearings), rebuilt the 2 carbs (yes it's a 3 cyl with 2 carbs), yet it still hardly ever runs right. 2 Stroke fumes didn't bother me much as a kid, they do now, in fact I don't like anything about 2 strokes and especially not messing about with fiddly needle bearings... I've thought about ripping the powerhead off (again) and seeing if I can graft on a 4 stroke car engine instead!
Have seen a few inboard engine'd boats with engine coolant to raw water heat exchangers (engine runs pressurised coolant similarly to a normal car) but I think raw water still runs through the marine special exhaust manifold. Marine exhaust manifolds are another rot spot, not far off the price of an engine and are more difficult to pick up second hand than engines.
Cast iron welding specialist?