Good day all, Looking for some guidance. Fora while now I've known that my cylinder 3 on my 4.9l '87 f150 wasn't firing. I finally got around to installing new plugs, and wires. When I start it, which it does, it runs exactly how it should, but it doesn't like starting, it usually takes 4-5 seconds of cranking these days to start, but is happy after that. Any thoughts?

 

A mistake is trusting the gap on spark plugs from the factory. If you didn't check gap I would recommend it. .044 is the suggested gap.
What brand and type of plug did you install? 1-5-3-6-2-4 is your firing order of the plug wires. Distributor turns clockwise.

 

I've installed motocraft bfs44ca, it's all Oreilly's had in stock. I pretty sure that the firing order is correct though, but I'll double check.
Thanks!

 

Tighten gap 3 thousands from spec.

 

If the tapered seat isnt clean I have found this can happen: It lead to rough running since my cylinder wasnt sealed technically, it also lead to loosening plugs but that was after a little while

 

Thank you very much! Cleaning the taper seems so obvious, and there were clear symptoms of that on the old plugs, as well as them being loose, I reckon that should fix more than one of my plethora of issues!!

 

I used a drill and a wire wheel to 1) reach 2) rough up the area. I had some fine sand paper that I used where I had buildup but I tried to keep the abrasives out of the equation. A little carb spray and a stick magnet help to. Try to limit the junk inside. IF you buy a thread chaser at the store (part store) for plugs, you can chase the threads. I was able to hand thread spark plugs in and then torque wrench them , 5 /6 are still ggood. I just didnt do 6 because it didnt have any issues and I cant reach it without a step ladder and it was hot as hell then. Im gonna do it soon since its cool so I have matching plugs.(platinum on 5 copper on 1)

 

the first three are my engine, Im just showing you incase you needed to reference plug wires and spark plugs positions. the last one is one that I had used for referencing

 

Thanks again! I've got the whole firing order figured out, I've just gone and done one at a time. Thanks for the tips on cleaning, I'll give that a go when I get home from school today.