carb flooding

after spending the last 3 months restoring the atmo finallygot back on the road to day only to get a tow back after a mile!!!. The problem seems to be the single carb flooding.car starts fine choke goes off and ticks over and revs fine. then fuel starts to come out of overflow and back into carb flooding it. l have rebuilt carb with kit and checkedfloat and new valve. i know the last owner fitted a new pump just wounder wether its the right pressure? . has any one else hasd thiproblem? any help would be apprecieted. brian.

What does the pump look like? It only needs a lifter pump.
About 3 psi and 90l/hr

IMG_20191007_140800.jpg

[mettersl]

When I first got my Atmo going I had flooding and starvation. Flooding caused by a new but no good needle valve, I suspect the parts available now aren't genuine and may not be of the best quality...another replacement solved that.
The starvation was caused by a blocked return pipe, this stopped the fuel pressure regulator working. The car would not go up steep hills,but was fine otherwise (a real puzzle).
If the system is working correctly, the pressure at the carbs is regulated by the fuel pressure regulator in the metering set up on the RHS of the engine bay behind and above the coil. The pump and filter up front should have no impact on the pressure at the carb. Might be worth checking that the front the rear pipes are flowing properly, but my money is on a sticky needle valve.

yes it looks the same as your picture magnet marelli no mam000841235509? not sure what psi. will check needle valve any idear were i can get areplacement. thanks to all for your help.brian.

[mettersl]

The single carb is used on renault 30 and peugeot 604, so not that rare, but solex france died a long time ago so spares are specialist items.
I googled the Carb, 34TBIA, and then called the most lily looking websites.
https://www.dellorto.co.uk/product-cate ... rs-spares/
http://www.webcon.co.uk/shopdisplayprod ... rburettors (I used these guys)
https://classiccarbs.co.uk/products/solex-carbs-parts
https://www.morepartz.co.uk/for-sale/ca ... ugeot/604/

Happy hunting.

lee

thanks lee forgot to say i tried both the new and the old vavles old one lasted longer ran fine before test run. the spindle that goes throght the float seems abit loose is it mnt to be tight. many thanks brian

[mettersl]

I guess it's possible that the fuel pressure is too high, but that will be the regulator not the pump.
Do you have a fuel pressure gauge to check?
The second carb is fed from the first, so maybe it gets marginally lower pressures, but otherwise it seems odd that both carbs aren't leaking.

[johnb]

The single carb is used on renault 30 and peugeot 604, so not that rare, but solex france died a long time ago so spares are specialist items.
I googled the Carb, 34TBIA, and then called the most lily looking websites.
https://www.dellorto.co.uk/product-cate ... rs-spares/
http://www.webcon.co.uk/shopdisplayprod ... rburettors (I used these guys)
https://classiccarbs.co.uk/products/solex-carbs-parts
https://www.morepartz.co.uk/for-sale/ca ... ugeot/604/

Happy hunting.

lee

Simon Auto have the overhaul kit 031021 which I used on my A310V6 which has the same carburettors.

Mecaparts also do the kit MP1010 and list the single choke carburettor membrane as MP1010A. Not sure whether this is included in MP1010. The illustration of the MP1010 kit doesn't show all the items but if you click the photo it does seem to have all the items except MP1010A.

https://www.simon-auto-shop.de/epages/S ... cts/031021

http://www.mecaparts.com/Equipement/pag ... page=10#ok

yes i did use the rebuild kit john and have sourced a spare needle valve so the battle goes on.!! one thing is when i took tank out ididnt mark pipes could i have put them on wrong way round? facing front of car does flow go left or right and would it make any difference? thanks brian.

[johnb]

Can’t help with that Brian as my A310 could be different to your GTA regarding the pipes.

[mettersl]

I'd need to look at the diagram to work out what happens if you send the flow up the return pipe to the pressure regulator.
If I was in your shoes, I'd get hold of a fuel pressure gauge and check what the pressure that carb is.
This kind of thing :-
https://www.ebay.co.uk/itm/Engine-Fuel- ... 3922458973

I'm not able to do it today, but I can take a picture of the plumbing on mine , pretty sure that LHS pipe (looking in direction of travel) is the return and the flow is the RHS (with the pump and filter in it).
If the fuel pressure is excessive, its the pressure regulator up near the RHS suspension turret that will be the culprit or the piping in that area. I have a complete spare of the pressure regulator and flow meter assembly I can photograph too, once I find it , but I'd measure the pressure first.

Good luck, it's worth it once they start working properly.

yes have orderd pressure guage and have found diagram in work shop manaulthat confirms what you thought but picture would be good! have new pump and needle valve and plan to strip out and clean return side wish i had done it when engine and gear box were out!! just hope flow meters alright but will worry aabout that when it happens .will let you know how i get on. many thanks brian.

[mettersl]

I managed to clear a blocked pipe in situ with brake cleaner and compressed air...the hoses are accessible from the engine bay and if air will pass through, so will fuel.
I don't think the pump will be the source as the regulator sets the pressure at the carb, not the pump. If the return line is blocked, the pump is stalled and this REDUCES the pressure as its a centrifugal pump (counter intuitive I know). If the flow line is blocked, you get fuel starvation.
The gauge will tell you about pressure in. Good luck...

On my Stag there was an issue as a replacement fuel filter and pressure regulator - Malpassi Filter king - effectively meant a nice reservioir of fuel sat cooking in the engine bay which caused no end of issues (especially hot starting). Once removed and back to original small filter no problems.