Ok. I have an 81 F100 with a 300. I hauled a small fiberglass bass boat to the lake and back, not even 10 miles round trip. Every since then my truck has not been running right at all. When i got back to my uncles it was dying while in gear trying to park the boat. When I went to leave after hauling the boat it took me forever to get it started, but I finally did and when i was going down the road it was acting like it was running out of gas (the guage said it was between and 8th and half and its right as far as i know) so i put some gas from a gas can in it and hauled as to a station. I put some gas in it and headed home. The truck was acting like the transmission was going out, it would quit pulling the start pulling again and so forth. So I let it sit in a parking lot and the side of the road over night. My stepfather and his friend went to tow it home the next morning because i had to go to work. His friend got in it and it fire up and he drove it probably about 15 miles to where i work instead of taking it to my house. I was looking at it while on lunch and noticed that the linkage rod seems loose where it connects to the bracket on the transmission, and that the passing gear isnt even hooked up. I was going to try and tighten it but the bolt goin through the bracket and where the linkage rod connects has a carter pin on one side and the nut stops so far up letting it still move (Automatic C4 trans if that helps anything). The transmission is pulling now but when its idling in gear it dies. It chugs down like it trying to stay running but shakes and rattles and after a 4 or 5 tries it dies. It was a little low on trans fluid, bout half a quart or so, so i put some lucas trans oil in it to fill it. I made it home from work (approx 7 miles) but it would sit there and chug along and die every time i came to a stop while in gear. It idles fine while in park or neutral but when its in reverse or drive it dies.

Someone suggested to me that it might be a vacuum leak, but i havent been home to check it yet.

Im just wondering if any of you guys would possibly know what is wrong with it. This is my only vehicle and i gotta bum a ride to work and back till i get it fixed.

Sorry for the wall of text but if you have any idea whats causing this I would greatly appreciate the help.

 

Sounds like a vacum leak to me also. Your carb might be tuned. Or your not getting gas fast enough. Possibly fuel pumps starting to go bad??

 

Or maybe a clogged fuel filter. Unhook the fuel line at the carb and crank it over with the coil wire pulled. Put your thumb over the end and see if it builds some pressure. Let it flow into a (1lb., or 12oz. whatever the heck they are these days) coffee can. It should fill it half full in a minute or under. The pressure won't seem like a whole lot, but the gas should go everywhere if you let it go, (kinda like a garden hose barely turned on).
If either one of these doesn't happen, you have a fuel delivery problem, which could be in the tank filter , any inline filters that may be present from the tank to the fuel pump, or the fuel pump itself. If you find a steady supply of fuel when disconnecting the line from the tank to pump (at the pump) via gravity, (maybe 1/4 coffee can in a minute), you can be 98% assured the problem is elsewhere.
If that checks out ok, with the engine off, the air cleaner off, move the carb linkage back (opening the throttle) while looking at the top of the carb. You should see 2 streams of fuel shoot down into the carb. If you don't, the problem is either a fuel filter between the fuel pump and carb, or the carb.
I should have probably told you to do this first, but carefully inspect all vacuum hoses for cracks and to make sure they are hooked up. If the truck was running OK before, they are probably not misrouted, but one may be leaking or unhooked.
You could have a leak on the intake manifold (not likely, but not impossible). There are several different agents you can use to check this ( ranging from oil to WD-40 to Propane to carb cleaner or brake cleaner), but carb cleaner is my favorite. With the engine running and idling, spray (or apply as indicated) the product selected around the manifold and carb base. If you apply it to an area where there is a vacuum leak, the rpm's will rise. ( This can even detect vacuum hose leaks as well).
I don't think it's related to a linkage problem (especially the down shift linkage you suspect, as it really only functions on WOT, not idle), unless it is an idle solenoid adjustment. If giving it slightly more throttle solves the problem, do that while looking at the throttle linkage and what to adjust should become obvious.
If none of this seems to be the problem, check the timing, (if you can), or have it checked at a quick lube joint. These folks are usually pretty good about doing stuff like that for free or next to it, especially if you get an oil change at the same time.
Since you were towing when it first started, it might be a bad torque converter,(or trans) but let's hope is one of these easier and cheaper probs first.

 

Ill check the fuel lines and filter when I get off work. I took the carb off and cleaned it about a month or two ago. I didn't change the filter but I took it off and spray carb cleaner through it, then covered one in sprayed sone in and shook it up. I need to just get another one for good measure.

I need to adjust the linkage anyway because it's hard to get it in park now. Sometimes it's starting and throwing its self in park. And that's not good.

That's funny cause I work at a walmart tire and lube but I can't do anything like check the timing because walmart has all kinds of retarded rules and policies. But I'll get a timing light and check it.

But I really appreciate yours guys help.

 

I had that simular problem about a month ago on my 81 F-100. It was stumbling at idle but you put the pedal down a little and it would run fine. The HUGE filter they had in those days put so much weight and it had the left nut/bolt (dont remember) that holds the carb to the intake manifold was loose. You can turn it with your finger, tightened that up and it runs fine now. I dont know it can be any of the above all sound about right.Taylor