Ok, I have a 1986 EFI 302 - Put new cam and lifters, chain, rear seal and oil pump and put back in truck. It turned over alot before gas made it to the rail. (I was worried about wiping the cam) When it did start it was running rough. Broke in cam 1500 for 15 min. When I backed down it stalled. Started it back up and it ran then stalled after about 1 min. Seems like if I give it gas it smoothes out, also it is running very rich (burns eyes). After messing with it for awhile, now it won’t start unless you give it gas. I haven’t checked the plugs yet, and didn’t put on new wires. How do I know if I damaged the cam lobes? Any other ideas or suggestions will be appreciated. Thanks, Red

 

It sounds like something went wrong here. I'm guessing the cam was off time, or not the proper cam for that engine. I'm not the expert on those engines, but I think the 351 / 302 have different firing orders. are you sure the cam is correct?

Anyway, here's what you need to do:
1. remove the valve covers.
2. remove all spark plugs and main coil wire
3. crank the engine over and examine the valve action, check to see if they all seem to be about the same.
4. if you question any of them, you can measure the spring height at the lowest point on each one.
hand crank the engine with a long wrench or bump the engine until the intake moves to the highest point (valve spring is compressed the most), measure and compare to the others.

You might be able to eyeball the cam with the valve covers off, you can on the FE.

Now do a compression test with the TB open and all plugs still out. The compression should be above 140 and should be nearly equal (within 10%)

Next recheck the firing order and dist placement (if you had to remove the dist) put the engine at TDC with #1 valves down and check roter is pointing to #1

Check for a wire not connected, the fuel system could be getting bad info from a temp sensor.

One other question, don't these newer trucks have some kind of computer readout setup with trouble codes?

>Ok, I have a 1986 EFI
>302 - Put new cam
>and lifters, chain, rear seal
>and oil pump and put
>back in truck. It
>turned over alot before gas
>made it to the rail.
> (I was worried about
>wiping the cam) When
>it did start it was
>running rough. Broke in
>cam 1500 for 15 min.
> When I backed down
>it stalled. Started it
>back up and it ran
>then stalled after about 1
>min. Seems like if
>I give it gas it
>smoothes out, also it is
>running very rich (burns eyes).
> After messing with it
>for awhile, now it won’t
>start unless you give it
>gas. I haven’t checked
>the plugs yet, and didn’t
>put on new wires.
>How do I know if
>I damaged the cam lobes?
> Any other ideas or
>suggestions will be appreciated.
>Thanks, Red

 

Thanks for the reply, I am sure that the cam and the firing order is correct. I will check the spring compressed height. If they all aren't consistant, does that mean that I damaged the cam? I will also do a compression check at this time. Thanks, Red

 

If they are not all the same, it means either bent push rod, bad rocker arm, bad lifter, worn cam lobe...
You should change the oil filter, tear the old one open and look for metal. Don't forget that hydro lifter will bleed down, so you want to give them time and some pressure to bleed down the same.
On some engines, you can remove the lifters easy and inspect the wear pattern, but the compression check should give some answers and it's the easist to do.

 

My 85 302EFI did the same thing until I replaced the fuel pressure regulator. I had bent the vacuum fitting while changing engines.

 

Ok, so far compression is ok, I'm not sure yet about the spring height. I opened the filter and don't see anything. Sometimes when I start the truck it starts without me giving any gas, sometimes it doesn't. Replaced plugs but still runs rough, even rougher with a load. Timing could still be off, as I dont have a timing light. Where is the fuel pressure regulator located? Thanks, Red.

 

That says it all when he said he doesn't have a timing light.
Why don't you get somebody to keep it running while you slowly
turn the distributor. Better yet, go buy a timing light.
Remember, you have to unplug a wire when timing the engine to
release it from computer control. I think it's a single wire
connector that goes to the distributor.

 

The wire you need to unplug is called the "SPOUT" signal wire.
It is yellow with a green stripe. It should have a plug
by-itself that you can unplug.

 

Thanks for the info. about the spout signal wire. I didn't know about that. I will borrow a timming light this weekend and see what happens. Thanks again.

 

tx064deer check on the cam if it is newer style HO cam it is what they call windsor cam and firing order will have to be changed