YFA Carburetor wont start

[Aaron Cherry]

I have a YFA carter single barrel carburetor and when i go to start my truck it wont start. I have to spray starting fuid down the choke to start my truck. once my truck is started it runs just fine, and when i turn it off as long as the engine is still warm it will crank right back up. i have a 1986 ford F-250 4x4, with a 4.9 L inline 6, 300 engine. does anyone know what might be causing this issue?

[Gary Lewis]

Aaron - Welcome to the Bullnose Forum!  Glad you joined.  

However, you may have missed the email I sent you, which asked you to go to the New Member's Start Here folder, read the guidelines, and then post an introduction in that folder.  We ask that because we hold everyone to the guidelines and since they are posted in that folder think it is wise to have everyone post there before posting elsewhere.

So, would you do that for me?

[1986F150Six]

Welcome, Aaron! After you reply to Gary's question, the following might be applicable to your situation:

https://www.ford-trucks.com/forums/1110073-choke-adjustment-101-a.html

[Gary Lewis]

Thanks, Aaron.  You've posted in the NMSH folder so I trust you've read the guidelines.

[Aaron Cherry]

i noticed that this is for thew cater YF carboretor but as i have the YFA would adjustment be any different?

[Gary Lewis]

They are very very similar so those instructions should be fine.  But you could also use the ones on this site at Documentation/Fuel & Air Systems/Carter YF & YFA 1 BBL Carbs.

[FuzzFace2]

Arron
You also did not say if this happens overnight or sitting for a week between starts?
Yes mine can sit for a week or more between trash runs and shows.

I say this because there can be 2 different issues going on here.
I did not read the link but a guess it has to do with the choke adjustment and the first place to start.

If it is after sitting for say a week then it is something else and let us know and can walk you thru what needs to be done.

BTW it is a known issue for our trucks to have a hot restart, lot of cranking before starting, and there are somethings to try to fix this also.
This is different than slow cranking when hot and a whole different way you need to go to fix.
Dave ----

[Aaron Cherry]

my truck wont start cold at all, if it is left without running for more then 2-3 hours i have to use starting fluid to get it going then it runs fine. as of yesterday though it doesn't matter how much fluid i use it wont start. i checked all the spark plugs and their gaps, i cleaned them all off and they all seem fine. what would be the next thing to check?

[Gary Lewis]

Did it get colder outside yesterday?  I'm trying to figure out what changed to cause the truck not to start, even with ether.

As for the next thing to check, I would check for spark.  Pull a plug wire and put an old plug in it.  With the plug laying on the engine turn the engine over and see if there is a good blue or white spark.

If you have a good spark then is the choke closing?  When the engine is cold and you depress the throttle just a bit the choke ought to close almost completely, staying open maybe 1/8" at most.

[JimJam300]

Had a similar issue after I messed with the fuel lines and tank on my truck with the YFA. I would start it with a gas can in the engine bay, or pouring fuel in the line from the top and hooked it up to the tank after it ran for a while, or if I had cranked it for 10 or so minutes. Not a carb guy by any means but to me that meant the fuel system was bad on the tank end.

[mat in tn]

let's keep this simple. drive the truck around a bit to get it up to operating temp. as close as you can to the temp where the problem occurs and then park it back at home and wait the same time as you would expect to have the problem. then open the hood and remove the air cleaner but be careful not to touch or disturb any linkage. get a good look of the top of the carb, take a good pic even. then see if the choke has tried to close. if not then look down the venturi and move the throttle 1/4 of its range while watching closely. if you see spray of fuel then you have not run the bowl dry. if you do not see a fuel spray then the fuel has gone somewhere or even not gotten the carb full.  
 the next thing to check can seem odd but it's a real thing. grab the carb by the top and try to wiggle and turn it in place. yfa carbs are a carb that screws to a baseplate which houses the butterfly. these are known for loosening up and creating an internal vacuum leak. sometimes masked by the choke being engaged yet shows up as a very lean start once warmed up and the choke is pulled off. if you notice it being loose at all you will need to remove the carb and tighten the screws from the bottom or by turning it over and spilling fuel. i hate fuel on me !! the screws are either a torx30 i think or a no. 3 phillips head depending on year and or whether it is new or a rebuild.
  the other possibility is a vacuum leak not at the carb. this could be any number of small hoses or even a vacuum operated device like the heat/ ac system.