1981 Diesel 2WD pickup “runaway”
 

I recently purchased a 1981 diesel pickup (“L Series” engine). It had been sitting in the weed for 15+ years. After a little bit of work I got the pickup running. The kicker is as soon as it start running it was like the fuel pedal was to the floor. It got up to very high rpm’s before we plugged off the intake and killed it. The pickup still starts fine but will basically try to run away if you let it. (Blows lots and lots of smoke)

The problem appears to be something with the injection pump. All the linkage going to it is good and working fine.

Any recommendations on what to look into?

There is not much info on injection pumps out there and very few, if any rebuild kits or even new pumps.

Would like to keep this project pretty cheap if possible.

Any info helps. Thanks!

Diesel runaways often have nothing to do with the injection pump. Given that this truck has been sitting 15+ years, you could have one or more of the following issues:
One or more stuck open injectors (fuel not regulated), worn or broken oil control ring(s) allowing engine oil to act like diesel fuel, Leaky or broken valve stem seals (same problem, allowing engine oil into the combustion chamber and acting like diesel fuel), possibly stuck open PCV valve (same issue).
You didn't say what mileage is on this truck, but it would have to be fairly high for it to be the rings. The other issues are far more common.

Most often it's engine oil getting into the combustion chambers without regulation and the engine is running away on that. Check your engine oil level; I'd almost be willing to bet it's low now.

I think what you may have is a model LN40 diesel truck; check your door tag to verify. If so (or even not so) here is a link to parts lists and diagrams for that truck:
https://toyota-usa.epc-data.com/pickup/ln40l/2453/

If a different model (LN50 or LN55) you can also use that site to find the relevant parts lists and diagrams. There is also this thread on Yotatech about an "82 injection pump: https://www.yotatech.com/forums/f114...repair-309817/

If it comes down to the pump (or any other not commonly US available parts), you may be able to find rebuild parts for it on Ebay. There are a lot of sellers offering kits, most of them either in southeast Asia or Australia, where these engines are more plentiful.