20 Most Recent 1981 Ford F 100 Questions & Answers

anything will fit with gentle persuasion from a oxyacetalyne torch and a mig welder

1981 Ford F 100 | Answered on Jul 09, 2018

There are several possible causes for this problem. Two of them from the newer gasohol fuel that was not used in 1981. I believe the trucks were the last vehicles to convert from carburetors to fuel injectors which originally were hybrid carburetors with injectors in the venturies.

The gasohol can dissolve the rubber valve in the front of the carburetors. The gaskets were not made for gasohol either. The rebuild kits for carburetors use a blue gasket which can handle the new fuel. The old gaskets swell and block the passages inside the carburetors.

You could check that filter you mentioned, seems like it is a low cost guess to replace as a possible solution.

Think about your past fuel sources, like where you could have bought bad gas. There are products like "HEET" which are suppose to draw moisture out of the fuel. It might help to try before you change filters and run the tank low with the additive and then put some good gas in; maybe a midgrade to insure octane rating.

1981 Ford F 100 | Answered on Jan 13, 2018

Hello Shinning5
Here's a source to the shop manual.
May have wiring diagrams.


1981 Ford F 100 | Answered on Dec 02, 2017

probably need to replace power valve in carb

1981 Ford F 100 | Answered on Nov 07, 2017

Make sure that the primary wire between the distributor ignition points and ignition coil is not damaged anywhere and grounding the circuit out. This is not a ground wire.

Replace the ignition points condenser, if this is shorted your points will never be able to work. With the condenser removed, use an ohm meter to check the resistance between the end of the condenser wire and the condenser caseing, there should be infinite resistance or an open loop, but it should not show any kind of a connection between the two, or it is grounded or "shorted to ground" and it will prevent the ignition system from working.

Are the ignition points adjusted properly? They have to open and close to send a dwell signal to the coil.

Connect a test light to ground and on the NEG. (-) side of the coil, have someone crank the engine and look for the test light to flash, the test light should flash indicating a dwell signal or coil pulse. (Do not use the POS. + side of the coil for this test, because you will not get a dwell signal).

If no dwell signal, then...

1. Turn off ignition and remove the distributor cap and turn the engine over until a high spot on the distributor cam lobe is on the rubbing block on the ignition points.

This is the fully open position for the ignition points and where they need to be to set them. and if you do not know the feeler gauge size, or the dwell angle to set your points at (according to manufacturers specifications), then tear off a piece of a match book and place it between the two point breakers.

2. Loosen the point hold down adjusting screw and move the base of the points with a screwdriver (look for adjusting nothches), until there is a light drag felt pulling on the match book. For the newer GM's up to 1974, just use a 1/8 allen wrench to obtain the same light drag on the match book.

3. Remove the matchbook and there should still be a small gap between the point breakers, rotate the engine and you should see the points open and fully close.

4. Pull the coil wire out of the distributor cap and ground the end of the coil wire well or you might get shocked.

5. Have someone crank the engine and re-check for a dwell signal, you should also see a blue-white spark flashing between the point breakers as they open and close.

If you now have a dwell signal then replace the distributor cap back onto the distributor and the the coil wire back onto the distributor cap, the engine should now start.

If you did not grease the rubbing block of the ignition points with die-electric grease when you installed them, then the rubbing block on the points will wear down prematurely, the points will close down, and the engine will no longer start.

If you crank your engine over and the ignition rotor turns clockwise (looking down at the rotor) then you need to put the die-electric grease along the right side of the rubbing block edge (looking down at the points) so that the grease is trapped between the points and the distributor cam lobe, and the distributor cam lobe can pick up the grease. (Grease the left side of the rubbing block edge if the ignition rotor turns counter-clockwise). Only use die-electric grease.

1981 Ford F 100 | Answered on Nov 21, 2015

un hook safety cables , lower gate till you see an opening on right side that holds gate ( a steel cup with one side missing ) lift right side past opening , lift out ,& up and pull to right to remove from left side.

1981 Ford F 100 | Answered on Oct 13, 2014

find the wires for the land right indicators and join them through a switch. So get the two lh wires together in on terminal and the two rh wire together in the other terminal and when you switch the switch on the power from one indicator lights powers up the other side as well

1981 Ford F 100 | Answered on Aug 02, 2014

here is a picture that i labeled to help you figure out the ones that you need. i hope this helps ~ Zach

1981 Ford F 100 | Answered on May 21, 2014

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