Poor mileage on my 85 300D--replace Injectors or IP?

[Carrameow]

I am having extremely poor mileage, somewhere around 16 to 18 mpg. This summer it was better at 21 mpg. I've heard that the standard for these vehicles is somewhere around 27 mpg which I once got even with a worn Injection Pump and a bad engine and stretched chain, but that was before I replaced engines. I know Brian is even getting 29 mpg on his 300SD.

On my new engine I am having "mileage" problems.

I'm pretty experienced with Diesels and I know all the leaky rubber line, ALDA, stretched chain & IP timing checks and I have done them. I have already replaced my chain and retimed the pump and replace all those leaky rubber hoses between the injectors.

Something is instinctively telling me to replace the Injectors or IP. I have a spare IP but having just gone through the exercise of pulling mine the last time when I changed the timing, I'm not thrilled about the huge Plumbing Job one has to do to switch it.

I know where a good set of injectors is. The trouble is they have been "exposed" for two months to the elements. Back in August, I found a heavily crashed damaged 300CD with 230K.I was tempted to even salvage the engine but I didnt have the time. I did however get the Injection Pump and a lot of auxilaries. Unfortunately I left the Injectors exposed because I took the lines.

Would there be any harm in using those injectors if I pulled them and if I blew them out? One thing I have never done is take apart an Injector