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Discussion Starter · #1 ·
i rebuilt my carb yesterday and put it on this morning. it idled nice and smooth for about 5 minutes, then it died. ever since then it will not idle.:banghead

i was wondering how far out your idle screws are. mine are as far out as they will go and i know this can't be right. anyone know what is going on with my carburetor. :confused:
 

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Screw them all the way in and the back them out about 1 1/2 to 2 turns and go from there. With them being all the way out, you're probably flooding the carb.
 

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House of Windsor 4ever!
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In the five minutes it idled, was it on the high or curb idle steps? First blush: you have a massive vacuum leak, possibly with the EGR spacer plate, or elsewhere on the manifold if you eliminated it. It'll idle just fine when cold and enriched, but take the enrichment away, and it won't run. Was this "won't idle" problem the reason you rebuilt the carb?
 

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Discussion Starter · #10 ·
In the five minutes it idled, was it on the high or curb idle steps? First blush: you have a massive vacuum leak, possibly with the EGR spacer plate, or elsewhere on the manifold if you eliminated it. It'll idle just fine when cold and enriched, but take the enrichment away, and it won't run. Was this "won't idle" problem the reason you rebuilt the carb?
i am pretty sure it was on curb idle. i checked all vacuum lines and the spacer plate is new. yes, i rebuilt the carb because it wont idle.
 

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Discussion Starter · #12 ·
i got it to idle and advanced the timing and got it to idle really strong. i turned it off to tighten the dist housing, went to turn it on and it wont idle now.

i have noticed that every time i got it to idle the choke plate is closed and when it dies the choke plate is partly open.
 

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That proves you have a vacuum leak somewhere. The intake, vacuum lines and PCV valve, vacuum brake booster, worn valve guides, etc. should be checked for leaks.
I've also run into something caught between the carb base, the EGR spacer, and the intake when I bolted down the carb. I even had a setup with no EGR spacer, so the power valve housing was up against the intake; broke the ear off the carb when tightening it down. Cost me $150.00 for a replacement.
 

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Discussion Starter · #17 ·
i checked vacuum and found that the brake booster was leaking. i plugged the port on the tree and also eliminated the pcv. i now know for certain that it dies when the choke plate opens. when i got it to idle i manually opened the choke plate and it died. how far is your choke plate open when the engine is cold and hot?
 

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Don't take out the PCV valve. In fact, replace it.
If the PCV system is not functioning properly, the flow of crankcase vapor into the intake manifold will not be properly metered.
This will wreck the fuel/air mixture for combustion and cause a rough idle
or it won't run at all. Don't know why I didn't think of that before.
 

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House of Windsor 4ever!
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i checked vacuum and found that the brake booster was leaking. i plugged the port on the tree and also eliminated the pcv. i now know for certain that it dies when the choke plate opens. when i got it to idle i manually opened the choke plate and it died. how far is your choke plate open when the engine is cold and hot?
On cranking, the choke plate should close down to the specification (and I'll come back to that in a sec); then when the engine catches, the plate should open a little more, controlled by the choke pull-off (which is adjustable. Then, after 30-45 seconds, rev the engine, and the choke t-stat should turn the choke cam from high idle to curb idle and the speed should come down 200-400 RPM and the choke plate should be almost fully open. Then one more rev, before you put it in gear, should pull the idle cam to low idle position, and the choke plate should be fully open.
 

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House of Windsor 4ever!
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Does your carb still have its number tag? It would've been held on the top of the bowl with one of the two bowl screws. If you do have it, give me the number, and I'll see if I have it listed and give you all the specs on your carb.
 
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