The brake booster is a good size vacuum line. You want to suck it into the intake and then let it sit. Once it has sat for 15 mins start the truck and let it run and burn the seafoam out. It will smoke a lot, but thats ok, it will be really clean afterwards.

 

well the expensive plugs are a waste of money. platinum is a bad conductor, copper is far better and your truck will run better with basic copper plugs.

did you recheck the timing with the spout connector removed.

 

Well I think it's dying a slow death. It won't run at all now, sputters and farts like its running on 2 or 3 cylinders (timing chain has skipped?). Went on a 150 mile road trip Saturday, all seemed fine (except the stalling at idle). After we returned home, I went to move the truck in the driveway and BOOM.....nothing. The rotor is pointing to 3 o'clock (#1 wire is a noon) when the line on the fliywheel lines up with the marker. Tried rotating the distrubitor to get it to run, but no such luck.

 

when you turn it over does it sound different almost like its spinning with no resistance? if so then your timing has for sure slipped or chain let go.

 

No, not like that, I spun the chain on my '69 Cougar years ago and it was just like that. But this? It's trying to fire, but no on all cylinders, it will turn by itself a few revolutions but shudders badly like only 2 or three are firing and quit. The plugs and wires are fine.

 

I am not sure I read a post right, did you say that the distributor rotor was not pointed at the right wire?

How did you replace the wires in the truck, i.e. did you pull the wires one at a time and replace before moving to the next or pulled them all and replaced based on the number 1 making on the distributor cap?

 

The wires are fine, I did them one-at-a-time, and the wires I bought are numbered. When it wouldn't start Sunday, the way it behaved I thought the chain had skipped or spun. I cranked the flywheel to line up the timing mark, and the rotor was pointing at the #7 wire (that would be roughly 3 o'clock if you use the #1 as 12 0'clock). But this is not exact and doesn't account for the 10 degrees BTDC, which is probably very close to 3 o'clock since the distributor rotates once for every 2 crankshaft rotations.

I'm now quite sure it's not the chain, but I dunno, it's at the shop right now.

 

Maybe check distributor drive gear. Maybe the metal got weak and broke. Only way it would not be out of valve time, while out of ignition timing. Pull the distributor out and check the gear. Maybe one of the cogs broke on the drive. I sold a guy a new distributor for his bronco II because he was missing two cogs. Maybe yours broke off.

 

might just need a new dizzy. Now i havent looke at my dizzy in awhile but isnt post #1 at 3 oclock. get out your haynes or chiltons manual and double check the wiring on the dizzy.

 

Haynes shows a 5.0L dizzy firing order. Looking at about 1:00 o'clock and going counterclockwise. 1, 5, cap clip, 4, 2, 6, 3, cap clip, 7, 8 then back to 1. Good luck.

 

Yes, thats the firing order. If the front of my engine was 6 o'clock, then my #1 is at roughly 11:30.

What I was meaning is that if you put a clock-face on the dizzy with #1 being 12:00, then my rotor was pointing roughly at 3:00 when the timing mark on the flywhell was lined up with the timing marker, which is roughly where #7 is. The truck ran fine until I changed the plugs and wires.

Coincidence or not, it has gotten worse and worse. I never changed the timing or altered the firing order. The code reader at the garage I went to wouldn't work on my truck. He says the computer is hooped. He told me I needed a new Map senser, which I replaced, which made no difference.

Now it won't start and I'm getting exasperated. Maybe a carburetor system is not such a bad idea, no computer to act up.

 

you just said what the problem is. you need to start truck getting to op temp. losen dizzy bolt,remove spout connector and adjust until the number 1 post on the distributor is around 1o'clock. then hook up a timing light and see where your at compared to the timing mark on the damper and get to 10-12*btdc. use chalk on the damper marks so you can see better.. your running rich because the dizzy is to far retarded.

Or you have the distributor cap on wrong.

 

You could pull the distributor out and reset it again or you can take all the plug wires off and find where the rotor is pointing at what lug when at TDC on the timing marks. The easiest way to find if the number one piston is at TDC is to take the plug out of it, put your finger in and have someone crank the engine over SLOWLY until you hear the air pushing past your finger, dont put anything down the hole including your finger. Then you can turn the motor over until it is at TDC on the timing mark. Then find where the rotor is pointing in your distributor and what lug it is at. That lug will be your number one lug, then follow the firing order on the distributor and go in a counter clockwise direction from number one plug wire until you are back to number one.

 

Everything you say is correct, but I was sure I had the wiring right and never messed with the timing before this problem began. I could not start the truck to get it to op temp.

As it turns out, a multitude of problems "synchronized" to create a difficult situation to diagnose.

The fuel pressure regulator was behaving erratically.
It was flooding the engine which was fouling the plugs (the black smoke).
I changed the plugs, it seemed fine.
It happened again, and eventually fouled the oxygen senser (the "hunting).
The code reader didn't figure it out.
The oxygen senser was so bad, and the fuel was so rich, the engine wouldn't start (the chugging, not starting, hence the "apparent" timing issue)

So.... replaced the fuel pressure regulator, oxygen senser, and plugs (again). It is like a new engine.

As for the sea foam idea, it may not be necessary now, as there was a ton of fuel in my crank case, so I would think it's pretty clean (yes, I changed the oil and filter...again).

I thank all of you who offered good advice. This site is invaluable to the do-it-yourselfers.

For what its worth, the mechanic who alerted me to the fuel pressure regulator problem told me that (in his opinion) Bosch plugs are not a good choice in domestic engines, as they will not rid themselves of minor carbon deposits like an NGK or Champion will. If they get the slightest bit fouled, it will increase exponentionally. They never get better. He also told me in his experience, which predates EFI, he has never replaced, or heard of anyone having to replace a MAP senser.

Anyone want to buy MAP senser, like new, still in the box?

 

sounds like you found a better mechanic. glad things got going for you. I would drain the oil again and replace the filter 1 more time. gas will wash the bearings and cause major engine failure. by the way dont use Fram oil filters ok.