WANTED Carb Vent Valve
WANTED Carb Vent Valve
Hi All
i think i have found the cause of my intermitent lack of power.
i believe it may be a dodgy solenoid in the carb vent valve.
i have searched everywhere to no avail.
i have been told i can just block the pipe (by Avonbar) but i thought it was supposed to help with hot starting so would prefer to replace it if possible.
my problem it that as soon as the turbo starts to produce boost the car dies like it has a lack of fuel. it is only intermitent and there are no split hoses.
i am going to try running with the pipe off to see if i get the same prob, then block it to see if it is cured. i am just waiting for a dry weekend first.
if anyone has a spare they would be willing to sell please let me know. i will give the pipe blocking a try before i change it just in case it is something else.
If you can help please let me know.
Thanks
Darren
i think i have found the cause of my intermitent lack of power.
i believe it may be a dodgy solenoid in the carb vent valve.
i have searched everywhere to no avail.
i have been told i can just block the pipe (by Avonbar) but i thought it was supposed to help with hot starting so would prefer to replace it if possible.
my problem it that as soon as the turbo starts to produce boost the car dies like it has a lack of fuel. it is only intermitent and there are no split hoses.
i am going to try running with the pipe off to see if i get the same prob, then block it to see if it is cured. i am just waiting for a dry weekend first.
if anyone has a spare they would be willing to sell please let me know. i will give the pipe blocking a try before i change it just in case it is something else.
If you can help please let me know.
Thanks
Darren
- Attachments
-
- vent valve.jpg (89.68 KiB) Viewed 23794 times
Re: WANTED Carb Vent Valve
Hi darren
have you tryed ebay or looked through the back of miniworld or minimag
regards
James
have you tryed ebay or looked through the back of miniworld or minimag
regards
James
GOT BOOST
Re: WANTED Carb Vent Valve
Yep. Ebay at least 3 times a week since the start of december
I have checked minimag & miniworld too.
i have also tried rover, minispares, med & avonbar.
Cheers
Darren
I have checked minimag & miniworld too.
i have also tried rover, minispares, med & avonbar.
Cheers
Darren
Re: WANTED Carb Vent Valve
thanks
Re: WANTED Carb Vent Valve
Hi
If I am looking at the correct bit, this was put on MG Metro's due to their tendancies to run on when you turned the ignition off, this in turn drew more fuel in as they created vacuum ahead of the carb and more fuel meant they run on a bit more, so Rover put this valve on that vents the vacuum to atmosphere as soon as ignition is turned off and thus solving the problem.
The valves though are know for sticking either open or closed. Sticking open would mean no boost closed would mean tendancy to run on a little. Shouldnt be that much of a problem on a turbo as they have lower compression.
I would blank it and see if you have power or boost issues.
However all issues I have had with ERA's arround intermitant boost and low power has been fuel pump or pressure or carburetor related.
Regards
Paul
If I am looking at the correct bit, this was put on MG Metro's due to their tendancies to run on when you turned the ignition off, this in turn drew more fuel in as they created vacuum ahead of the carb and more fuel meant they run on a bit more, so Rover put this valve on that vents the vacuum to atmosphere as soon as ignition is turned off and thus solving the problem.
The valves though are know for sticking either open or closed. Sticking open would mean no boost closed would mean tendancy to run on a little. Shouldnt be that much of a problem on a turbo as they have lower compression.
I would blank it and see if you have power or boost issues.
However all issues I have had with ERA's arround intermitant boost and low power has been fuel pump or pressure or carburetor related.
Regards
Paul
Re: WANTED Carb Vent Valve
Thanks Paul
I have already rebuilt the carb when i first had the problem.
I have a brand new regulator to put on it if i don't have any joy with the pipe.
The fuel pump will be the only thing that will not have been changed after that, so i will have to see what happens.
see you at the shows.
Darren
I have already rebuilt the carb when i first had the problem.
I have a brand new regulator to put on it if i don't have any joy with the pipe.
The fuel pump will be the only thing that will not have been changed after that, so i will have to see what happens.
see you at the shows.
Darren
Re: WANTED Carb Vent Valve
hi
If you have a low guage worth plumbing in this to the fuel supply to tha carb, and routing the pipe out the bonnet vent and then have the gauge under a wiper so it can be viewed while driving.
When driving about you should then get a static fuel pressure about 4.5PSI without checking, it shouldn't fluctuate flutter or drop or peak, if its doing anything weird like that then look at pressure regulator, these are factory set though I have had to tweak two of them on mine to get the correct fuel pressure. If you can't maintain relaible pressure swap the fuel reg, if its still not right then suspect the rest of the fuel system.
As yours is a replica what did you do for fuel lines pump and tank?
Paul
If you have a low guage worth plumbing in this to the fuel supply to tha carb, and routing the pipe out the bonnet vent and then have the gauge under a wiper so it can be viewed while driving.
When driving about you should then get a static fuel pressure about 4.5PSI without checking, it shouldn't fluctuate flutter or drop or peak, if its doing anything weird like that then look at pressure regulator, these are factory set though I have had to tweak two of them on mine to get the correct fuel pressure. If you can't maintain relaible pressure swap the fuel reg, if its still not right then suspect the rest of the fuel system.
As yours is a replica what did you do for fuel lines pump and tank?
Paul
Re: WANTED Carb Vent Valve
Hi Paul.
The fuel feed is standard mini (metro is identical) the fuel return is a large bore galvanised pipe of the same diameter as the metro return pipe. I have put the return into the top of the tank opposite the filler neck.
i will try the pipe with the valve first, but if there is no difference i will give the guage a try.
See you soon
Darren
The fuel feed is standard mini (metro is identical) the fuel return is a large bore galvanised pipe of the same diameter as the metro return pipe. I have put the return into the top of the tank opposite the filler neck.
i will try the pipe with the valve first, but if there is no difference i will give the guage a try.
See you soon
Darren
Re: WANTED Carb Vent Valve
Hi All
i think the vent valve is the problem. i disconnected the hose from the valve and the car ticked over nicely. i got the engine up to temp then drove down my road. as soon as boost started i lost power as if there was fuel starvation just like i had experienced before. I had a job to keep it ticking over but after a 10 seconds or so it would tick over ok.
I blocked the pipe and i flew. i went out for a drive and it was a bit spluttery at 30mph but after i got back i richened the mixture a little and it smoothed out no end.
The only problem it gives is a little overrun now
Only about 50 miles till it is run in and can get it tuned. MOT due in 2 weeks so i will see about rolling roading after that.
I hope this will sort it out for the show season.
see you soon
Darren
i think the vent valve is the problem. i disconnected the hose from the valve and the car ticked over nicely. i got the engine up to temp then drove down my road. as soon as boost started i lost power as if there was fuel starvation just like i had experienced before. I had a job to keep it ticking over but after a 10 seconds or so it would tick over ok.
I blocked the pipe and i flew. i went out for a drive and it was a bit spluttery at 30mph but after i got back i richened the mixture a little and it smoothed out no end.
The only problem it gives is a little overrun now
Only about 50 miles till it is run in and can get it tuned. MOT due in 2 weeks so i will see about rolling roading after that.
I hope this will sort it out for the show season.
see you soon
Darren