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1986 f-150 4.9L inline 6 with YAF 1 bbl. Can't figure part located under carb.

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Eric's 86 f-150

1986 f-150 4.9L inline 6 with YAF 1 bbl. Can't figure part located under carb.

Rusted piece connected to large hose. Connects to 3-4inch piece with hex nut on end.

Any help identifying this part and where to buy a new one? Truck idle is very rough now almost wants to stall out when initially stepping on accelerator.

1986 F-150 Lariat 2wd, 4.9L engine, YAF 1 barrel Carb.

85lebaront2

Re: 1986 f-150 4.9L inline 6 with YAF 1 bbl. Can't figure part located under carb.

Administrator

If you are pointing to the rusted out piece, it looks like the Thermactor system check valve. On the YFA carburetors, first thing to check is the float bowl to throttle body joint (it is the one between the aluminum bottom portion and the gold part above it) if you can get any movement there, then that is the problem.

Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

mat in tn

Re: 1986 f-150 4.9L inline 6 with YAF 1 bbl. Can't figure part located under carb.

i hope that check valve is sealing, or it could get loud

Eric's 86 f-150

Re: 1986 f-150 4.9L inline 6 with YAF 1 bbl. Can't figure part located under carb.

Thanks for the tip. It has gotten loud. Having a hard time finding the part. The auto part stores that have a replacement are telling me my truck takes a shorter version of this part. As you can see my part is 3-4 inches long. Theirs looks like 2 inches long in the photo. (No one carries it in stock) Another problem I am having is getting the old one off! Too funny. Been spraying it for 2 days with penetrating oil. Scared to torch it being so close to fuel. About ready to get some metal tape and jerry rig it.

1986 F-150 Lariat 2wd, 4.9L engine, YAF 1 barrel Carb.

mat in tn

Re: 1986 f-150 4.9L inline 6 with YAF 1 bbl. Can't figure part located under carb.

well it threads into the plate between the carb and the intake itself. not a real difficult task to remove it and place in a vise in order to get a real wrench on it. that plate is aluminum btw, the steel part threaded into it is a taper thread 3/4npt i believe, i have "seen" them with a pipe plug before. heck you may not even have to get new carb mount gaskets.