Detroit 60 12.7 cyl3 misfire

Drove to look at a truck I'm considering buying. Guy told me it has a cyl 3 mis and thinks its an injector. He has an extra one. Take that with a grain of salt. Temp on cyl 3 is lower.

Is there anything I can do to make sure its not anything major? Injector or doing an overhead adj is cool id really not rather deal with a dropped valve or bad cylinder or something.

It starts right up, doesnt smoke. He says no oil water or diesel mixing. I suppose id have to sit and let it run for quite a while to see evidence.

Scanner I can buy, taking the intake manifold off, maybe a scope? What can I do?

 

Thank you. Trucks a 91 i suppose I can grab a scanner?

Any mechanics in the mo area?

 

Yeh...then I may have to reconsider... I dont want to do an inframe out the gate. My truck just caugt on fire, was totalled out, and paid off. I got 1500.00 bucks. Would have been 2500 except for the deductible. So this is what I have to work with money wise. I wanted to go with pre eld and less expensive I don't however want to dive into a hole. I understand the slightly oxymoronic situation believe me...

 

Im thinking about it...he said it has sat, (sold his other truck, works on a farm now) he had to clean the tanks to get it running but only got one cleaned good...; I peeked into the other tank and I was thinking varnish but I just ran across some pics and it actually kinda looks like algae /varnish. Any chance that could be it?

 

And yes I would but this is bfe Missouri, Ive also sold an item or two and didnt give as much of a #### as I should, but thats not typically how i sell things. Clean it up disclose the issues and let the chips fall‍♂️

 

I havent messed with detroits before but Im assuming I can pop the valve cover off and inspect that right? Dude doesn't have a problem with me doing it.