So as a new old truck owner I am learning new tidbits of useful info by the day. Now that I've got the oil leak down to a couple drips per day I was gonna work on a few creature comfort things.
We'll start with the idle and vibration. My wife really wants to drive the truck but the rough startup idle and the vibration of the cab and bed have her a little unsure of safety. I've put 2k miles on her already and I'm comfortable with the structural but she isn't.
I guess the questions is, where to start with rough idle and cab/bed vibration? Motor mounts, cab mounts, bed mounts? I'm assuming there's some sort of bushings that can be replaced that have disintegrated over the years. Remember, my replacement capabilities have to be doable in the driveway. I don't have a lift.
I know lot of folks have posted on rough idle and some trace it to vacuum issues. Without knowing my rpms it's hard to know if my idle is too low or high, which could also be making the vibration worse while sitting still. Any pointers on how to reduce the vibration/ where to look would be appreciated.

 

I've lost track over the weekend. Are you the one that needs new and better spark plug wires? A FULL tune up would prolly negate the engine from running too rough. Right down to even new vacuum hoses. Make sure the PCV valve is on the suction side of the PCV system. ( carb spacer to r/s valve cover the closest). Cap, rotor, wires, fuel filter, air filter, PCV valve, Motorcraft spark plugs, vacuum hoses, any and all rubber it may need. Like belts.

 

That's a negative on the weekend discussion.
Belts are new, plugs are new, ac filter is new. Will check pcv and fuel filter.
Spark plug wire brand and size recommendation?

Any suggestions on the body vibration?

 

Sounds like you need some basic tools, timing light, vacuum gauge for starter.
#1. Check for bad dizzy vacuum advance
#2 points gap
#3 set timing
#4 adjust carb.
#5 set idle rpm's.. no tach then you'll have to guess.

Don't know all the specs, look in glove box hand book manual, If none then you'll need to find out this stuff. Or buy a manual covering your truck for starters.
Orich

 

Motorcraft wires are good. Not too pricey. You may want to clean and gap the points. Generally the truck stops working if the points and or condenser are in need of maintenance or replacement. Could need a mixture adjustment on the carb. Also could be a vacuum leak which could be detected by using an unlit propane torch allowing the gas to flow around the base of the carb and see if the idle changes if it pulls in gas.

 

Well, depends on what's causing the vibration. I assumed the engine is not running smooth considering all the stuff the PO rigged via "presidential solution".
1st you have to figure out what's causing the vibration. Do you feel it JUST idling or when driving also? If when driving also is it worse when? Does it look like the PO replaced the original 302 with a later model?

 

1972 F100 WITH A 302:
PCV....D0AZ6A666A (EV50)...Discontinued so buy a Quality Name Brand one.
Spark Plugs.....BSF42C (SP420). Next time you buy plugs buy Ford Motorcraft ones. Still available on-line, your local Dealer, or from me at my dealership. PM me if interested in a price.
PLUG WIRES....D1AZ12259A,replaced by D6PZ12259A, replaced by D6PZ12259AR, replaced by E5PZ12259NR. This also still available on-line, your local Ford Dealer, or from me at the Dealership I work at. PM me if interested in a price.

 

Ya, is the shaking from the motor idling or while driving down the road? Can you put motor in neutral/idle and the truck still shakes?

A good solid tune up and setting everything "right" will help with motor shaking. If it is while moving, then you need to check U joints, tires and things of that nature. A bum tire will give the truck a shake that you can chase for eternity.

 

Mostly when sitting at the stop lights is where the shaking begins. While driving I can feel a slight bit of surge in the pedal in a sort of "methodical way"...if that makes any sense.
The vibration doesn't really exist when moving or at least it's not noticeable.
I have no reason to believe the motor is different. Not that I'd know what to check for. The PO didn't change it since he had it or so he told me.
The motor itself doesn't appear to run rough. It doesn't stumble or have pedal lag.
I'm wondering if it could be something as simple as motor mounts. Surely they can't be hard to change and after 40+ years, it might be worth doing just to eliminate something basic. But I think I need to do plug wires too.
I haven't messed with the carb mixture settings because I'm a newb with carbs...rofl, and honestly don't want to screw it up after I spent all that time last time getting it to run this well.

 

Sounds to me that your engine's vibration dampner is bad. This is the piece that is behind the crankshaft pulley and has the timing mark on it. This part helps balance the engine and absorb vibrations in the crankshaft. With the engine running look at the vibration dampner. Is it spinning smooth or wobbling? Wobbling is not a good thing and prolly what you'll see. Also crawl under the truck. With the engine OFF grab on to the outer part of the vibration dampner. If you can spin it by hand it's bad.

 

Motor mounts will not cause a rough idle. To check them put one foot on the gas and one the brake with the transmission in drive. If the mount is bad the engine will stand up a little. To check the opposite side do the same in reverse.

 

Not reviving a dead thread here but I did want to follow up so it's not just another. " SO WTF WAS IT" thread with no ending. after replacing my spark plug wires getting new plugs and gapping them to the right dimensions.... the rough idle is virtually gone. The plugs were toast. And while I didn't realize it at the time... I had flooded it two times badly in a matter of a couple weeks which surely didn't help the plugs life span. Some of the hesitation when starting from a stop has gone away too.

 

So what about the points any replacement of them??
Orich

 

I actually still havent touched the points yet. Being a novice at working on the dizzy and such I'm a bit nervous to get in over my head. Sounds like a simple enough job, but this is my daily driver so I can't get into something that could lead to something else.... yada yada yada and end up with the truck not running for a few days.

 

You might think about buying a Pertronix Ignitor and coil. No more points or timing to mess with ever. Less than $100 @ amazon.