How hard would the conversion be for a 12 Valve Cummins in a 65 Ford F100

 

Not all that hard. It's going to be very tight though. I was going to do this very swap as a next truck project. I think the 91-93 Dodge intercooler will fit. Another thing to make it easier, some guys use a manual pull cable instead of wiring the shutoff sol. There's adapter available to use Dodge's 47RH/RE, GM TH400, Allison(SAE pattern), and I think a C6 also. I'd say to stick with a trans that has an overdrive.

 

Your truck is no where near strong enough to handle the twist or weight of that cummins. You should plan on seriously beefing up your suspension if you intend to go throuhg with this.

 

If you're still thinking about the convert, You should watch where the oil pan reservoir is, If you've got a 65, it'll have twin I beam and steering behind the axle. thats where the sump is on a 5.9. I am planning to power a 66 F100 with a small diesel and a T5 5spd so we can afford to drive it for more than just shows. Truck is for the wife and the diesel will remind her of her ARMY days, thats what she says about driving my VW. A3.9 cummins would probably work better for a F100.

A 5.9 would be fine if you're not planning on pulling anything, otherwise you'll have to beef up the chassis and the front coils. Bunjee frames are not fun!

 

The easiest way of "beefing up the frame" is to purchase a rusted out, but well running cummins Dodge pickup about the same wheelbase as your F100, then make new body mounts, and sling the body from the Ford frame, to the Dodge frame.

Then everything is strong enough, in the right place, and aside from body mounts you'd have to make some wiring modifications and find a berg fitting to use the Ford column in the Dodge, so it "looks right".

Long time ago a friend of mine swapped a cummins into an 86 full size bronco (I think it was an 86... maybe it was an 84...) anyway, the bronco body was moved over to the dodge frame, which had the body mounts moved and the frame/driveshaft shortened.

Came out really nice too. He should have repainted the bronco body while it was off... but oh well.

 

If you can get a rusted out cummins Dodge cheap it will propably be a pre 94 and they had frame strength problems even when they were new. If you could find a 94 or later dodge they are somewhat better but seem to bring big money here in the Great White North where rust is king. If you want a strong frame, use a pre 1980 Ford F350 Chassis/cab frame and your cab/front will bolt on and you box will line up with the frame all you have to do is drill your own holes, and shorten chassis to taste. Your 1/2 ton I beams will even fit. Don't Dodge IT!

 

I would also say try the 3.9 instead, then at least you keep the 1/4 or 1/2 ton part of it. Also those trucks came factory with a 4cyl diesel. Maybe not the F-100s but the 3/4 and 1 tons would have.

 

The only diesel application back then was in a "P" series Ford and I don't think I have ever seen one. It was a UK built 6cyl diesel, but I can't remember who, Leyland comes to mind but don't quote me. The P series was a stepvan . I agree that the 3.9 cummins would work excellent, but they're hard to find in a "road" application. We had a77F250 with a 6cyl industrial Isuzu diesel and it was an interesting truck to drive. It was underpowered, so full throttle was usually the position anyway. I think you can still buy one of those w/an adapter to a C6 for irrigation pump use.

 

Hmm, I'll have to take a look and see if i can find the owner's manual for my buddy's '69 F-100 and see if i can find out what it says again. I know it said dump a teaspoon of either down the intake to start it, thats just what stuck in my mind.