My `86 F250 had the tach not reading correctly or most of the time not at all.
I figured it was the sensor on IP housing.

Did some reading about swapping different things that worked. I wasnt going to spend $70 just to get the tach working. But didnt mind being creative.

I checked the old sensor and had no continuity. I dug out an old crankshaft sensor left over from a Jeep 4.0. It had mounting wings to attach to bell housing. Cut them off with a hack saw and ground down the plastic.

I took a punch and knocked the plastic center and magnet from old sensor. The Jeep sensor dropped right in and was flush with bottom of threads like old one was. Mixed up some JB Weld and glued the two pieces together.

Cut the pigtail and spliced in the original connector. Plugged it up and now a perfect working tach.

One more problem worked around. I have been chasing the bugs on my truck for the last 5 months since purchased. Tomorrow is its maiden voyage for any significant miles being put on it. It will be put to work this weekend and hopefully without issue.

 

Awesome, Sweet hack ... It is just a very simple VR sensor!

-Enjoy
fh : )_~

 

Yup, good work.
These also work the same way and there seem to be quite a few out there: Honeywell Variable Reluctance Speed Sensor 2874A003 Perkins Engine 728062 02 New | eBay
For $10, if you don't already have a usable sensor, this will work, but it also requires modification.

 

If someone had a catalog of pics to search thru, they could find one with a pigtail that would be easier to adapt. I stated looking before remembering there was a used one sitting around here somewhere.

 

Good job! When I bought my 87 I had completely forgotten about how many things need attention, repair or replacement - (just from age if no other reason) on a vehicle 25-30 years old. At my age and health condition it's not easy to do the work so it's going slow. Therefore it's going to be a long project. It didn't look 'old' to me and this is the truck I wanted. It just became an unexpected fairly long term project that I instantly became passionate about because I love the truck for exactly what it is and what It will be when I am finished.

I won't mention here all of the reasons I like it - there are very many. Yes, I unexpectedly bought a "project" with work and money needed but it instantly became a passion to make it a very nice truck when it's done. Compared to gas trucks which are a dime a dozen I consider this one a treasure.

I wish you the best on this 'maiden voyage.' You have done a lot of work on your truck! DO come back to this topic and let us know how this 'maiden voyage' went. That will be coming up next month for my truck - 600 miles, full bed and loaded 5x10 construction/utility trailer towing over a mountain range and then back empty. A "shake down cruise" and it is going to be FUN!
That is what I bought this truck for - one or two long hauls over several mountain ranges pulling a trailer. After that, some local work for it also towing the same trailer and probably a fifth wheel.

Off topic: I have sound insulation on the firewall, the inside fender wells and under the hood. I don't know if your 86 has that. It was still loud inside because I had no carpet. THEN I put a nice carpet in it recently (from an F350 parts truck). It is now quiet inside and and it sure is a pleasure to drive now! Front end was aligned a couple of weeks ago after new Moog tie-rod ends and now I can drive it anywhere. (needs more work though but nothing mechanical or in the drive train)

Check your private messages for 2 relating to the VRV for the C-6.