Hi all,

I have recently bought a vehicle with the 250ci 6cyl running the stromberg carb, the Fuel is via a fuel cell through an electric fuel pump. the problem I have is the motor starts sweet, idles sweet, but as you get down to about half throttle the motor coughs, f@rt and backfires and dies.

Would anyone have any ideas what to start with getting this motor running sweet, I've changed the Plugs (all were carbon fouled) leads and Dizzy..
I'm thinking maybe the pump is overfueling??
What pressure should the pump be pumping fuel to the carb??


Help Please

Cheers

Tony

Try replacing the fuel plunger in the carby, I'd use a leather one if you can get it as they last longer than the neoprene.

G'day,I'm a bit worried about the electric fuel pump - its not for an EFI car is it? If so, its probably providing way too much fuel pressure for a stromberg... from memory, you should be looking around the region of 7 - 10 psi for a carby application like this, EFI pumps can be like 10 times this pressure - if so, it might be overwhelming the needle and seat in the carby...

If this is the case you could look at a regulator - or , if its just running a strommie on a 250, hook it back up to the mechanical pump only, they're up to the job...

remove the electrical pump and go back to the mechanical one. the electrical one is giving too much fuel pressure,thats why it back fires and stall's when you give it rev's. its fine at 650 rpm's but go back to the mechanical one,they go for ever and never f**k up.

Its funny, Mark-xdf, was reading your comment and it reminded me of once, on an XA, I had one stuff up - near Ceduna, and found an old cortina abandoned by the side of the road. It had been there for years and years, it was a six and half the engine was actually buried in the dirt - I had to dig down about a foot to get to the fuel pump - unbolted it, not thinking it would be too good but worth a try - dismantled it that night in the hotel room in Ceduna, full of mud and crap but seemed OK. Put it back together and ran some water from the tap into it (in the hotel room this is) give it a pump on the lever and it shot muddy water across the room and up the wall...so it worked...put it in the next day, was still in that car when I sold it, never gave any probs.

huh????

I don't get what you mean by huh? Just saying that what you said about their reliability reminded me of that story..