Have you verified the terminals at the coil are not corroded, mine were a while back.
Are your spark plug wires in good shape ?

With your issues, and what seems like, lack of ability, it might be better to find a local repair shop and have them trouble shoot the problem.

 

the spark plug wires are new.

to be fair i did remove engine from the head gasket up and replace almost all systems then reassemble. i also replaced most of the lifters, adjusted engine timing, replaced most hoses then worked on the fuel system. the truck is extremely old and maintenance was not regular so when i do take parts off what ever is connected to it breaks. its very true that i have compound issues and its hard to run diagnostics for me on something mechanical vs a computer then it would be easy. your generation grew up with a wrench helping dad in the shop, my generation grew up with a ide running on a single core pentium while making pages on geocities. i remember in the past thread there was some doubters on if i could reassemble the engine and get it running and i did. i have ruled out major areas of trouble for the engine and its very much a problem of "problem of the gaps" where the areas where i can focus on narrow.

 

I understand what you mean about of a different mind set. I find electrical stuff, hard, at work, when the Design Engineer came down to trouble shoot a problem that the Test Engineer didn't understand, I found it easy to follow the Design Eng, when we worked together.

So, you should be able to follow the things the experts here will tell you.

Take a step back, look things over, and think about it.

Again, make sure all the electrical and vacuum connections are good.

Have you used a vacuum gauge to set the adjustment screws on the carb ? you want to move the screws until you get the highest vacuum on the gauge, 17-18 is the # your looking for. My may have to adjust idle to keep it in spec.


Hard starting, is that slow cranking, or does the engine spin at normal speed but not firing up and idling. Does it sound like it's not getting fuel during the starting process?

 

I dont have a vacuum leak tester but i will order one. Since i dont have that i still checked for leaks.

My findings are:

1. the vacuum multi port has dirty threads and does not seal enough, the hoses lack clamps. While the hoses themselves are not leaking how they connect do leak. here is a picture: https://i.imgur.com/necLbsd.jpeg
2. in this picture: https://i.imgur.com/7Zb84CR.jpeg there is a round large brass connection to the right of the egr, it has a black hose that snakes to the left over the exhaust manifold - everything about this part has leaks including the hose. My guess is the hose must have been in contact with the manifold and burnt a hole but the hose needs to be replaced, and the bass needs to be removed, cleaned and put back on.
3. when i installed the carb on the intake port I only installed a single gasket, turns out there is a gasket i did not install that connects the egr to the carb.
intake (engine) -> missing gasket here -> egr assembly -> gasket for carb -> carb

method for testing:

i did not use a vacuum tester tool (dont have) and i refuse to set the engine on fire using carb or brake cleaner and spraying that everywhere. the safest method i found was using propane. i have a 100k btu weed dragon propane torch. I turned the torch on low then passed propane over the hoses, if i found a leak the engine rpm increases.

intake manifold gasket missing, multi port vacuum leaking, hoses ok, large round bass hose and connection leaking.



I did install the new ignition coil and was super easy. I cleaned the terminals and the mounting bracket and the wires it was just covered in oil and dirt, wire brushed everything. Even when its probably not needed ill leave the new one on because its painted and just looks better.

 

OH MY OH MY
I can tell you you got a lot not right going on in this picture and why it may not run.
See where all the hoses connect to the vacuum tree under and to the rear of the carb?
Remove all the hoses from it. Find a hose that fits the nipples of the tree that is long so we can make plugs.
Also find screws or small bolts to fit tight in the hose. Cut the hose long enough to fit on the nipples and get a screw / bolt in it.

The hose going to the front of the carb and to the thing in the valve cover (the PCV in the cover). The hose for the PCV needs to go on the fitting just below the carb that you have the other large hose on that looks to be going over to the drivers fender where dose that go?
The hose hooked to the top of the carb remove it as that is for the choke.

At this point you should have all vacuum ports plugged off with short hoses with bolts / screws in them and the PCV hooked to manifold vacuum.
From what I can see you should be able to start the motor and have it run so you can adjust idle speed, timing when up to temp.

Dose that large hose going to the drivers fender go to the power brake booster?
If so find a nipple on the vacuum tree that will fix and make sure it is tight.
In the picture below the small hose connected to the lower right of the carb where dose the other end go?
I hope not the EGR valve. Remove it from what ever it is connected to and put a screw / bolt to plug it for now. Will it run better now!


We still have some hoses we need to track down and hook up but the motor should run with out vacuum leaks now.
Let us know how it goes and we can move on from there.
Dave ----

ps wish you were close, 5 to 10 min I could have this vacuum hose thing all fixed for you

 

https://imgur.com/a/0aO4YHu

https://i.imgur.com/6N6EdQw.jpeg
https://i.imgur.com/nOi11bk.jpeg
https://i.imgur.com/xfSrPMn.jpeg
https://i.imgur.com/NOXqdw2.jpeg
https://i.imgur.com/WXhWUF8.jpeg
https://i.imgur.com/3MnRTTI.jpeg
https://i.imgur.com/mkUgm46.jpeg
https://i.imgur.com/57FnpP2.jpeg
https://i.imgur.com/FdmonQd.jpeg

i routed the important stuff to the manifold and kept it as minimal as possible.
-brake booster to lower manifold tree

everything else i put plugs on it.


So I can start the motor no problem, i can get it up then put it under load. Then about one minute under the highest load the engine chokes, sputters and turns off.

 

The hoses look good for now but we will have to come back and check / hook some of the others up but I just wanted to get the vacuum hoses hooked up that was needed to run.

When it "chokes out" when under heavy load is it like someone turned the key off or like it ran out of gas?
When it "chokes out" when under heavy load will it restart?
If not under a heavy load will it stay running?

I am trying to see if it is running out of gas or no spark.
When it happens, with motor off choke should be open, look down the carb and move the throttle do you see gas squirt?
If you see gas squirt then you need to check for spark. Remove the coil wire from the dist. cap and hold it 1/8" from ground and crank the motor.
Look for spark and if it is good you should hear it "snap".

Once we know why it "choked off" we can look into fixing that.
Dave ----

 

When it "chokes out" when under heavy load is it like someone turned the key off or like it ran out of gas?
It feels like gas is temporarily restricted, the engine restarts with no issues like it never happened.

If not under a heavy load will it stay running?
It only chokes out under heavy load.

The inline filter that is next to the fuel switching valve has never been changed but i always change out the inline filter that is next to the carb. So that filter has been in the truck for maybe 20+ years.

So today i will change that filter out (ordered that part last night should arrive in the store today) then for good measure ill change out both filters along the fuel line including the carb because its only like 10 dollars. I will also blow the fuel lines with compressed air to ensure nothing is causing a restriction, then ill check engine timing. The alternator has been making a squeaking sound but it works i have been thinking of just replacing it. I also want to change out all the pulleys. Now if it is spark and the alternator is failing i would think we got a suspect that it wont be able to keep up with the voltage/amps the engine is drawing right?

So yesterday I fixed the vacuum leaks and i replaced the ignition coil, today ill be swapping both fuel filters out and rechecking ignition timing and also feeling out the distributor wires to the plugs maybe some issue exists got to rule it out.


I readjusted the timing and it was at 6 before top dead center and moved it to 10 seemed it came out of alignment. I bought the truck up to a heavy load and the engine stalled. So nothing has changed. The engine is running very very smooth with little vibration.

 

Dont do too many changes at once!
If it runs worst you will not know what of the changes caused it.
Same goes if it runs good but more if it runs bad.

I dont understand the "choke out"?
If it is like the key was turned off it just shuts off.
If it runs out of gas it spits and sputters before it stops running.
Depending how it"chokes off" will depend on were to look for fixing.

I would do this first and test.
There should not be a filter before the switching valve so someone added that.
If it has not been changed like for ever then it is good to change it out.
Also change out the rubber hoses. You can do the filters & hoses at the same time as it is fuel and I think this is the issue but?

Bumping the timing from 6*BTDC to 10* BTDC should not change the choke off.
But as a test when you do check / adjust you will have the vacuum hose off the dist. and plugged as you should.
Before hooking the hose up do the test under heavy load and see what happens.

Hook a vacuum gauge to intake vacuum when doing the tests.
what is the vacuum reading at idle no load?
Vacuum at 2500 no load?
Vacuum at under heavy load before it chokes off?

BTW how are you doing the heavy load testing, driving and throttle to the floor or foot on the brake and throttle to the floor?
Dave ----

 

Great news!

So i picked up today an air filter, inline filter, and a carb inline filter and changed everything except for the air filter i think i can get a few more miles out of that. When i pulled off the inline filter that is located next to the fuel switching valve omg... Well for one i could not stop the fuel flow, i had opened both tanks to ensure no pressure build up was in the tanks but that was not the case it just came out so fast. Then the fuel filter was stuck to the fuel line. The diameter of the fuel line is the same as the diameter of the filter so a bit larger bit of tube is used to fit on top / though the smaller line. I had to yank the tube off and i need to recheck it because it looks like it has cracking but seems fuel tight but for best practice it needs to be replaced. So i reattached the new one, tightened everything down and that was not complicated.

The fuel filter connected to the carb had its own issues, the bolt connected to the metal tube that is flared was not wanting to come out so i cut into the fuel line then removed the filter from the carb. I reflared the fuel line then attached the bolt into the fuel filter. i always have problems attaching the flare + bolt into the fuel filter it never wants to thread but that took about 10 minutes and was the most difficult part of this job. I reconnected the negative battery terminal then started the motor and the fuel filter was not leaking from the flare but leaked very little bit from the connection to the carb so i tightened a very little until no vapor came off and i saw no gas. So both filters are on, and not leaking.

When i took off the inline filter next to the switching valve it was completely clogged, it looked like brown, light red sludge ill cut it open so i can examine it more. Also the inline filter to the carb was very clogged to because of the first filter. It had not been changed in at least 20+ years. I think because from time to time i add seafoam into the tank that might have broken down stuff in the fuel filter and caused the clog, i have also been banging in that area trying to fix the fuel switching valve so i must have knocked something lose.

I started up the truck and its running great im going to stress test the engine a bit more to confirm it was a clogged filter causing fuel starvation. fuel, air, compression + spark, so we did indeed break the triangle. So far i have not been able to stall the engine. Since its 105 degrees outside and the truck has no ac (something i got to work on in the future) i cant test drive it right now but ill test it later today.

I tested the manifold vacuum and the result is 15 pounds of pressure so its a little low.

 

Good to hear you may have found the problem, plugged filter(s).
That brown / red stuff is most likely rust. Let it dry a little and then look at it and rub a little on a white paper towel bet it will look like rust.

When it cools down and you did more testing and you are happy we can look at more of the vacuum likes as I believe there are 2 or 3 that need to be hooked up yet.
Dave ----

 

Keep an eye on it. If the filters clog again, you are going to need new tanks. Very common on these trucks.

 

I was able to use the vacuum gauge when setting the idle screw to get the engine into the 17-18 range i tried getting high pressures then that and found it impossible because i would just turn and turn the screw. If i screwed the screw in i could stall the engine or get less then 10 pounds vacuum pressures but with about 2 1/2 turns was over all best. So the engine is in good shape because it has high vacuum pressures vs somethings <15 pounds.

 

I am very grateful for the help but i got another problem: the tail gate handle is broken its very hard to open the tail gate. Are there any rebuild kits where would i source the items.

so far i found this:
https://www.summitracing.com/search/...rd/model/f-150

its internal damage so ill have to disassemble and figure out whats going on.

 

Funny, my truck had the same issue in the rusty tail gate about 2007, I went to the local junkyard and bought a used, rust free tailgate. Well, a few years later, its levers did the same thing. That's when I put eye bolts in the tailgate top edge and use a turnbuckle to hold it closed.

But my truck is not a good looking truck, but it runs well.