i have a 69 amc ambassador, after driving 3-5 mi it chokes out, but after 30 mins or so it will run again, why

Question

its a 290, im running 2 battarys, i had to replace the starter relay switch, from trying to start it when it stalls, it had melted the + termanel, also replaced fule filter fule pump

Answer 1

the choke heater tube in the intake is clogged or broken and should be blanked off if a exhaust leak is present the choke element should be replaced with a electricaly heated one from a mid eighties fuel feed back ford product [still used the motorcraft 5200 series as a base] note if choke opens too quickly after conversion use a chrysler electric choke resistor in line with the choke power wire you just made up , these can be obtained from almost any year 225 slant six w/a 1barrel carb. if it opens too slowly you may need to run a heater hose up close to the element for extra heat also a 190 degree thermostat will help. your going to have to play with this but, if patiant it will work better than it ever did when new.

Answer 2

sounds like the auto choke is sticking

spray some Gumout on the carburetor - and let it sit a few minutes

then spray again and force it in the nooks and crannies
where cables run snf things move with the carb

or get a mechanic to look at it for you

PS may also be a vascuum hose that is leaking?

all the best!

Answer 3

nice car :)
it would be a carb problem, but i think its an internal seal on the carb, or the carb float is stuck. if its the 304/343/360/390/401 v8 then id just go get a new edelbrock carb- theyre easy to set up and readily available, and will get better mileage- if its the old 258 i-6 then youll probably have to rebuild the one you have

Answer 4

could possibly be with dealing with the charging system and the battery, you will be running on the battery but then it runs out but while sitting there it charges. have to get a new alterantor would be my guess but talk to a mechanic first.