help wiring colours

[bully]

Can some one help me with some info please.
I'm fitting a pair of su hif44e carbs to my triumph 2000. I have no loom from the ecu to the carbs. I've got info for all connections except the 5 wires to the plug on the stepper motor. I know which colours leave the ecu but not the order they arrive at the plug.
Could some one take a peek at theirs and let me know using the diagram below please. I'd be very grateful.

__
/ 1 \
|2 3| loom connector looking into it
|4 5|
----

Regards..Brian

[Russ]

Do you really want to fit thse carbs Brian? Most people want rid of the ecu and the problems it causes. I dont know if its still available but there used to be a kit you could get that replaced the stepper motor with a choke quadrant.

Cheers

Russ

[bully]

Can some one help me with some info please.
I'm fitting a pair of su hif44e carbs to my triumph 2000. I have no loom from the ecu to the carbs. I've got info for all connections except the 5 wires to the plug on the stepper motor. I know which colours leave the ecu but not the order they arrive at the plug.
Could some one take a peek at theirs and let me know using the diagram below please. I'd be very grateful.

__
/ 1 \
|2 3| loom connector looking into it
|4 5|
----

Regards..Brian
Hi Russ, I didn't know man choke conversions existed. I'm converting the old girl to LPG and am hoping to use the solenoids on these carbs to enable automatic switching from petrol to gas rather than having to switch the pump off and basically run out before manually switching to gas.

Regards.......Brian

[Russ]

Ah right, can you get the linkages for twin electronic carbs?

[E_T_V]

Fairly sure the solenoids won't completely cut off the fuel on the carbs, but it will lean out the fuel massively so it may work just as you plan.

[bully]

Ah right, can you get the linkages for twin electronic carbs?

Made up my own linkage with small ball joints. Starts and runs but obviously on choke. Could take stepper apart I suppose and set mixture when warm, Might be difficult to start though without at least 1 carb able to be choked.

Brian

[Russ]

If you are good at electronics (or know someone that is) Why not replace the ECU with a stepper motor driver,I think maplin does a kit but not sure if it will run the carb motor. I thought of this many years ago when I had my turbo but it never went wrong. I wanted a rotary switch for a choke control.

Russ

[bully]

If you are good at electronics (or know someone that is) Why not replace the ECU with a stepper motor driver,I think maplin does a kit but not sure if it will run the carb motor. I thought of this many years ago when I had my turbo but it never went wrong. I wanted a rotary switch for a choke control.

Russ

Back to square 1 Russ, I will still need to know the order in which to connect to the 5 pins on the stepper motor.

Brian

[G Force]

Hi Brian

1. Orange White ECU pin 6
2. Orange Slate ECU pin 10
3. Orange Blue ECU pin 7
4. Pink Blue ECU pin 8
5. Orange Green ECU pin 9


Cheers Gary:)

[bully]

Hi Brian

1. Orange White ECU pin 6
2. Orange Slate ECU pin 10
3. Orange Blue ECU pin 7
4. Pink Blue ECU pin 8
5. Orange Green ECU pin 9


Cheers Gary:)

Hi Gary.
Thank you very much, thats brilliant.
All the best.......Brian

[G Force]

__
/ 1 \
|2 3| loom connector looking into it
|4 5|
----



Hi just to clarify something Brian the wire positions I have supplied for you are as connected to stepper motor. So that is to say as viewed from the back of the plug where the wires run into. I think looking again at your diagram if you view the plug looking directly at the female pins then you will need to transpose 2 & 3 and 4 & 5 on the info I provided. Hope that is ok for you.

Just picking up on your reasons for converting the carbs to HIF44E, using the overun fuel cut off valves (ORFCO Valves) will only weaken the mixture they won't cut the fuel off 100%. It might make the transition from petrol to gas a bit more seamless but you will still need to cut the power to the fuel pump.

I also think that you will eventually run into problems with the orfco valves sticking open when you return to petrol from gas, this will cause flat spots and poor performance running on petrol.

Im all for the idea of converting to autochoke using the stepper motor set up though, that will be an interesting modification for your triumph. I don't know what cars you sourced the carbs from but the Rover SD1 2000, 2300, 2600 around D & E reg all ran a twin carb HIF44E set up with no vacuum switches, they used a more advanced ECU that indexed more stepper motor steps for acceleration enrichment on choke, which proved more reliable than vaccuum switches. The 2000 would be a closer tune to your triumph in terms of needle profile and choke enrichment, you would also have the bonus of probably being able to easily sort the linkage making the carbs easy to balance.

Cheers Gary:)

[bully]

Hi just to clarify something Brian the wire positions I have supplied for you are as connected to stepper motor. So that is to say as viewed from the back of the plug where the wires run into. I think looking again at your diagram if you view the plug looking directly at the female pins then you will need to transpose 2 & 3 and 4 & 5 on the info I provided. Hope that is ok for you.

Just picking up on your reasons for converting the carbs to HIF44E, using the overun fuel cut off valves (ORFCO Valves) will only weaken the mixture they won't cut the fuel off 100%. It might make the transition from petrol to gas a bit more seamless but you will still need to cut the power to the fuel pump.

I also think that you will eventually run into problems with the orfco valves sticking open when you return to petrol from gas, this will cause flat spots and poor performance running on petrol.

Im all for the idea of converting to autochoke using the stepper motor set up though, that will be an interesting modification for your triumph. I don't know what cars you sourced the carbs from but the Rover SD1 2000, 2300, 2600 around D & E reg all ran a twin carb HIF44E set up with no vacuum switches, they used a more advanced ECU that indexed more stepper motor steps for acceleration enrichment on choke, which proved more reliable than vaccuum switches. The 2000 would be a closer tune to your triumph in terms of needle profile and choke enrichment, you would also have the bonus of probably being able to easily sort the linkage making the carbs easy to balance.

Cheers Gary:)
Hi Gary
Thanks for clarifying that. My carbs and ecu are indeed from a Rover 2000 SD1 but came without the wiring loom. I'm hoping to be able to switch to gas on the first falling rpm, ie. first gear change so it may help to have a bit of petrol going with the gas initially while the engine is still cold. I'm hoping it will start on gas when hot. I have it setup to kill the pump on switch over. Thanks for your help, I will post up the result, success or otherwise, when I complete the project.

Regards.......Brian

[threelitre]

Apart from the complexities of changing a pair of carburettors and keeping the correct mixtures etc... (i.e. fitting needles with the same profile for a start).

I would like to comment on the use of HIF carbs with a LPG conversion. The biggest problem will be that during prolonged use of LPG the needle of the carb will wear away the jet. These carburettors, as well as later HS6 use a spring-loaded needle, that is in constant contact with the jet, rubbing the needle up and down the same spot on the jet opening all the time. When running on petrol this will only very slowly increase the jet size, as the petrol is lubricating the contact area. But when running LPG this will lead to the carb going out of tune within about 1000 miles, rendering it untuneable after about 10000 miles or so. After I found this on my Maestro I keep the needle in the door pocket, only to fit it when the need arises (about once per year or less).

The way around this would be to use older HS6 carburettors with the fixed, centred needle. These will not show the aforementioned problem. The also have another advantage: The HIF44 being empty most of the time will lead to a leaking float chamber after some time, because the seal will dry and shrink. The HS has got the advantage of a float chamber being closed by a lid on the top.

Thinking about the problem why you wanted to install the HIF44s to start with: On my Maestro, as well as on all other (carb-based) LPG conversions I know, the petrol pump will not be switched off, but a solenoid in the fuel line between the pump and the carb will be closed. This prevents the pump from going dry (and fail after some time). The disadvantage is (as on all non fuel injected cars) is that the float chamber will have to be run empty before the car can be switched over to LPG, which can be a bit unpleaseant when driving in town.

I thought of a possible way around this problem: The aforementioned HS6 carbs use a small rubber hose to connect the float chamber with the jet. If it would be possible to create a new connection incorporating a very small valve, then the switchover can be made spontanous, just like on a fuel injected car, as the float can be left full of petrol, just the connection to the jet will be closed off on the flick of the switch.

I have been thinking about this, but the extreme rare use of petrol I have now - usually to get me to fill up in case I did run out of LPG - does not warrant so much effort. In fact I have thought about removing all the petrol stuff from the car...

Regards,

Alexander

Edit: Oh, and about starting: The Maestro starts on LPG straight away in all weathers down to -10deg Celsius... If the ignition is good then this will not pose any problems.

[bully]

Apart from the complexities of changing a pair of carburettors and keeping the correct mixtures etc... (i.e. fitting needles with the same profile for a start).

I would like to comment on the use of HIF carbs with a LPG conversion. The biggest problem will be that during prolonged use of LPG the needle of the carb will wear away the jet. These carburettors, as well as later HS6 use a spring-loaded needle, that is in constant contact with the jet, rubbing the needle up and down the same spot on the jet opening all the time. When running on petrol this will only very slowly increase the jet size, as the petrol is lubricating the contact area. But when running LPG this will lead to the carb going out of tune within about 1000 miles, rendering it untuneable after about 10000 miles or so. After I found this on my Maestro I keep the needle in the door pocket, only to fit it when the need arises (about once per year or less).

The way around this would be to use older HS6 carburettors with the fixed, centred needle. These will not show the aforementioned problem. The also have another advantage: The HIF44 being empty most of the time will lead to a leaking float chamber after some time, because the seal will dry and shrink. The HS has got the advantage of a float chamber being closed by a lid on the top.

Thinking about the problem why you wanted to install the HIF44s to start with: On my Maestro, as well as on all other (carb-based) LPG conversions I know, the petrol pump will not be switched off, but a solenoid in the fuel line between the pump and the carb will be closed. This prevents the pump from going dry (and fail after some time). The disadvantage is (as on all non fuel injected cars) is that the float chamber will have to be run empty before the car can be switched over to LPG, which can be a bit unpleaseant when driving in town.

I thought of a possible way around this problem: The aforementioned HS6 carbs use a small rubber hose to connect the float chamber with the jet. If it would be possible to create a new connection incorporating a very small valve, then the switchover can be made spontanous, just like on a fuel injected car, as the float can be left full of petrol, just the connection to the jet will be closed off on the flick of the switch.

I have been thinking about this, but the extreme rare use of petrol I have now - usually to get me to fill up in case I did run out of LPG - does not warrant so much effort. In fact I have thought about removing all the petrol stuff from the car...

Regards,

Alexander

Edit: Oh, and about starting: The Maestro starts on LPG straight away in all weathers down to -10deg Celsius... If the ignition is good then this will not pose any problems.
Hi Alexander,
I really appreciate your input. This is still a very grey area for me and any hints,tips and advice is welcome. This installation is on a triumph 2000, (my other car is a diesel Maestro clubman). If it turns out I can start it ok without using petrol then I like your idea of removing the needles. To take this a step further, do you think it would run ok on gas if the complete needle assembly could be held up to the top of the dashpot?. Just a thought.

Regards Brian