Good luck
Mark
spent the best part of the day in the wind and cold fitting the 40's and new ignition system to my pinto.
wired everything up, plumbed everything in decided to go for it. ignition was a mile out so sorted that got a spark when needed and in the right
place.
fettled with the dizzy and in the end started but missing so again fettles the dizzy a bit, only made it worse not better. do the idiot checks make
sure all 4 are sparking and sure enough they are. starts engine took plug leads off 1 at a time and basically 3 and 4 made no difference at all.
conclusion, no fuel!
so there's my situation, 1 and 2 are getting plenty of fuel and running perfectly but 3 and 4 are getting nothing. took the top off the carb
checked the floats they are moving fine and there's fuel in the float chambers but it's going nowhere from there.
whats next to do folks?
bit worried i might learn a harsh lesson here about buying 2nd hand carbs from ebay!
Your jets are probably blocked.
Unscrew them and soak in carb cleaner.
Also get a copy of "how to build and powertune webers and dellortos" - will help a great deal.
S
May sound like a daft question but have you checked that the linkages between the two carbs are, well linked. and activating both carbs at the same time. have a look down the throats and see if the butterflies are opening. just a thought?
carbs are both working together all linked up.
i did think jets steve but my dad argued with me about it being both sides letting no fuel in but i have to confess i work mainly via guessing with
carbs! basic stuff i can handle but all i work on is oil burners at work!
By the process of elimination theres no harm in taking the jets out and soaking them as steve suggests, at least then you'll know its not them. Failing that it may be a top off and have a look job, will probably mean an overhaul kit though. Good luck!
Double check inlet manifold gaskets/seals are not leaking on rear carb . No/low vacuum causing no suction on fuel?. Does the engine run OK with open throttle ? if so sounds like rear carb is not open enough. Adjust on balance screw . Try screwing idle screws in fully and turn out a couple of turns . If/ when running on all four balance the carbs using balance tool or small hose to listen to suction. While you have the jets out check them all and note the sizes , make sure each is the same? at least you should have a starting point for jetting . Also check the choke sizes are all the same. Are the carbs a matched pair? check the numbers
I thought I had that problem once - turned out it was my head gasket failed between pots 3 & 4
Good luck
Mark
You havn't got No's 3 & 4 plug leads the wrong way round have you?
Paul G
rusty, manifold is as tight and it's gonna get, tightened everything up before trying to start it. makes no difference really what position
throttle is in it still misses but when i open the choke on the carb for 3/4 it runs faster but still missing?
also with the engine not running, open the throttle fully and i get vapour out of front carb but nothing from the rear.
mark, shouldn't be a head gasket problem i hope! it ran fine last time i had it out before i fitted the 40's
quote:
Originally posted by 907
You havn't got No's 3 & 4 plug leads the wrong way round have you?
Paul G
With it running on 1 & 2, squirt petrol in the carb inlet of 3 & 4.
If it's blocked jets it should briefly run on all 4
Paul G
Simple things first
Most likely case is the carb (throttle) balance between the front and rear carbs is a mile out
After that you have to set the balance then set the mixtures then rebalance then the mixtures again.
fuel float valve stuck shut is another possibility ( no fuel to resovior will mean no fuel to jets )
Long shot but what about swapping the two carbs over if problem stops with the suspect carb at least you know where you are heading.
does the beer mat trick work with those in the same way as a blocked su ( ie getting it running and blocking it of so it pulls neat fuel through ?
Just a thought
regards agriv8
Hi John
I had a similar problem when I set mine up, it turned out to be the balance between the front and rear pair. When I balanced them and set up the idle
mixture they ran fine.
Keith
Keith I've ggot a pdf file here on DCOE's that might help you out. U2U youe email and I'll send it to you.
quote:
Originally posted by john_p_b
when i open the choke on the carb for 3/4 it runs faster but still missing?
also with the engine not running, open the throttle fully and i get vapour out of front carb but nothing from the rear.