bad acceletator pump?
Thread Starter
|
Senior User
Joined: Sep 2009
Posts: 379
Likes: 0
bad acceletator pump?
i got an 86 bronco with a 4.9l 1 barrel carb. the truck died on me the other day in which it backfired trhough the carb and just died. it ended up being the distributor but now my carb isnt working right.
it seems when you pump the throttle by hand i dont see any gas dripping into the intake. i did rebuild it then got it running then it would only run for a certain amount of time then die unless i really gave it gas.
- now i did buy an adapter kit for a 2 barrel carb down to 1 to see how that works. i got a GM rochester twojet carb i rebuilt and now when i threw the carb on it only ran for a sec then died. now the only way it will run is if i spray starting fluid in it. i pulled the line off and it is getting gas but maybe the bowl isnt filling up. i see no gas pump into the intake. when i spary starting fluid in and open the throttle it goes into high idle.
on both carbs could it be a bad accelerator pump?
im thinking i might just save up money and buy a rebuilt 1 barrel for the truck. i would like to try a two barrel to see if i can get a little more power.
it seems when you pump the throttle by hand i dont see any gas dripping into the intake. i did rebuild it then got it running then it would only run for a certain amount of time then die unless i really gave it gas.
- now i did buy an adapter kit for a 2 barrel carb down to 1 to see how that works. i got a GM rochester twojet carb i rebuilt and now when i threw the carb on it only ran for a sec then died. now the only way it will run is if i spray starting fluid in it. i pulled the line off and it is getting gas but maybe the bowl isnt filling up. i see no gas pump into the intake. when i spary starting fluid in and open the throttle it goes into high idle.
on both carbs could it be a bad accelerator pump?
im thinking i might just save up money and buy a rebuilt 1 barrel for the truck. i would like to try a two barrel to see if i can get a little more power.
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
The answer is: you're not far enough into your troubleshooting yet to know. If it's dying one second after you start it up, the accelerator pump hasn't even come into the equation yet. The accelerator pump only comes into play when you open the throttle and increase RPM suddenly.
Is the choke closed when you go to start it for the first time (cold)?
Is the choke closed when you go to start it for the first time (cold)?
Thread Starter
|
Senior User
Joined: Sep 2009
Posts: 379
Likes: 0
i got it to run on the one barrel but it idles weird like it is high sometimes then low then sometimes dies but when i was bringing it to stoarge it would die every stop light i slowed down at, my dad thinks it is a bad float. but i rebuilt this carb. i did adjust the timing so it would run better so now i might try the 2 barrel again to see if it works otherweise i will just buy a rebuilt one barrel. if i go the one barrel route can i just change the jet to a little bit bigger to try and get a little more power out?
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
Bigger jets aren't a "performance upgrade;" they are sized based on what is required by altitude, engine displacement and RPM among other factors. For each use case there is a small range that's optimal, anything smaller is too lean; anything bigger is too rich.
Thread
Thread Starter
Forum
Replies
Last Post
EDMist
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
4
Dec 20, 2009 09:48 PM
boggerted
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
12
Jun 2, 2008 03:50 PM
ghunt
General Automotive Discussion
4
Nov 18, 2007 12:42 AM
matareno
1948 - 1956 F1, F100 & Larger F-Series Trucks
3
Nov 1, 2003 08:25 PM
