I have a 1986 F150 300 6 that has a 1 bbl carb. However, I was told I have a EFI engine because its gray and 1989-86 had blue engines. I'm thinking everything remains the same other than the carb part. Do I use different plugs or gaskets or internal parts? I've been talking auto parts store I have an 86' engine. Should I be telling them it's a carbonated 87-96 engine? Please some clarification on this as I didnt see any threads related to this topic

 

SD, sorry no one answered this question for you.
EFI motors did not have an opening in the block for the fuel pump. It had the boss and I think the 2 bolts holes maybe drilled & threaded but I am sure no hole for the pump.
On the head there are a few extra holes for manifold bolts think on the ends but not 100% sure on that also.
I would not worry about the color paint used on the motor, heck it could be painted purple, as long as it has a carb that is how I would order parts for an 86 motor / truck.

Now I will toss in a wrench.
Your 86 truck would of come from the factory as a feed back system. It used a computer to make fuel adjustments to the carb and timing to the dist.
Over the years some of the things that tell the computer how the motor is running go bad and you cant get a new part.
That computer go into "limp mode" and makes the motor run like crap. Because you cant get a new part we do what is called a DSII retro fit.
We change out the feed back carb for a non-feed back 80 - 82, and do the same with the dist. you will also need the dist. wiring and the ICM that bolt to the inner fender.
Then you can remove all the feed back wiring, hoses & computer and have a good running truck again.

Now you may want to check to see if someone had not already done the DSII swap.
Does the carb have a lot of wires going to it and does the dist. have a gray box with a lot of wires to it also?
If so they would be feed back. A dist. with a vacuum hose is non-feed back.
Dave ----

Oh welcome to FTE

 

I can't remember the dates Bill said, but I'm pretty sure if was way before EFI days when factory swapped to gray paint. Look for the engineering ID number cast on the block. Passenger side I believe. Post what you find and we'll decide it for you.

 

Think you are right, I forgot to say once I got my motor de-greased I found gray paint on it.
it is not a EFI motor I painted it blue and ordered parts for a 1981 truck.
Dave ----

 

Ford switched to grey paint for the 83 model year. Some early 83's were still fitted with blue painted engines as the previous years stock was used up.
If you have a grey engine in an earlier vehicle chances are it has been replaced or painted at some point and time.

 

My son's 1984 with 4.9L as well as my 1986 [now sold] 4.9L engine came original with grey colored engines.

 

My 86 block was blue with factory gray valve/ timing/ push rod cover. I am thinking it was a warranty replacement or rebuild. You have a computer controlled carburetor. Just order parts for the 1986 but verify first they are for the computer model you have...