Backfiring And Popping Carb

[Guest vigor]

Hi there have a 1993cc pinto that is playing up, when pushing throttle down fast it delays then pops in the carb then picks up but it is very sluggish and when decelerating it backfires a lot. have taken the carb apart a 30-34 dfth weber. Found a little bit of rubbish in the carb filter and can see some in the inline filter but looks as though its flowing ok. Any one know where I can find a diagram of the carb have looked on web.. Found the jets in the center with the 2 emulsion tubes and blown these out with bike pump are there any more jets in the carb? have checked the float needle valve as well. any other ideas would be welcome.

cheers John

[Guest ncoll]

Hi there have a 1993cc pinto that is playing up, when pushing throttle down fast it delays then pops in the carb then picks up but it is very sluggish and when decelerating it backfires a lot. have taken the carb apart a 30-34 dfth weber. Found a little bit of rubbish in the carb filter and can see some in the inline filter but looks as though its flowing ok. Any one know where I can find a diagram of the carb have looked on web.. Found the jets in the center with the 2 emulsion tubes and blown these out with bike pump are there any more jets in the carb? have checked the float needle valve as well. any other ideas would be welcome.

cheers John

 

Hi

for a diagram look in the haynes manual for ford sierra 1982 -1993. The carb was fitted to 2 litre models from 1985 onward.

 

neil

[agent_zed]

i had the same. used my compressor to blow through. If you can get some rubber tubing about 4/5mm and tape it (or secure it somehow) to the airline then cut the tube at an angle so you can put the tubing up into the venturi and get it onto the tiny holes that i think are the idle jets. You can see them just by the butterfly valves. Then you can blow through the other way than you probably already have.

 

Check the accelerator pump is clear. If you look down the primary venturi there is a small arm sticking out which should squirt fuel out when you pull the throttle open (engine should be off).

 

With the engine running if you manually pull the arm that opens the secondary venturi you should see the fuel vapour being sucked out of the venturi. Careful not to over rev the engine.

 

These are things ive done and it eventually worked, might not be the proper way to do it, so if anyone can see a reason not to do this feel free to say. hth

[Guest Deano 777]

you could also try carb cleaner, or add a cleaner to the fuel tank and go for a drive, have you checked you ignition timing? Dean

[Guest vigor]

Hi guys well I am happy to report that I have found the problems

 

1, poping back in the carb and and running like a pig was the timing, rotated the distributor about 5degrees anti clockwise and no more popping in carb and it goes like a rocket now.

2, backfiring when decelerating is caused by the 4 into 2 manifold joint to the stainless pipes...can rock the pipes and feel the movement.

 

thanks to all for their suggestions and help

 

cheers john