I have a Military 1984 6.2 CUCV, my current problem is that my bearings on the crank-shaft siezed. I am in the process of trying to replace the engine. The 8th digit on my vin number is "J", but I have v-belts not serpintine. I am going to get a lonk block from a remanufacture source. What should I be asking for? I am assuming the Military 6.2 is not the same as the civilain 84 6.2, correct? I am looking to do an apples to apples replacement, not an apples to prunes replacement.
I really need to get this truck on the road again ASAP so any help would greatly be appreciated.
Thanks

The J code on the 6.2 doesnt specify serpintine belts. that kind of belt sytem came into play in the early 1990 trucks I believe.

as far as the military trucks and blazers go, the 6.2 engine was pretty much the same as the civialian models. all military trucks had J code engines, and only difference I know was a more HD IP that could handle several types of fuels.

civilian trucks/suburbans/vans came with C and J code models, while C code engines were in blazers as well. after a 8000GVWR(I believe) the J code engine was specified.

J code specifies the HD version of the engine. where the C code had the EGR in the intake manifold and a lesser duty model of the IP, the J code had no EGR and a higher fuel delivery type IP. engine itself is pretty much the same between the 2 codes.

as far as military 6.2 goes, the HMMWV was an exception. I beleive there might be a few more differences, but the addition of exhaust headers, and a different type of intake manifold was a few.

remember your CUCV should be a 24 volt system. minor changes will have to be made to a civlivan setup engine but I doubt anything extensive. perhaps the starter? find a 80 something civlian 6.2 and drop her in. I believe there are other posts on here about the 24 volt situation.

only real 24v thing on the mil engine is the starter...

look on ebay, tons of military takeouts listed!

buy any running 6.2, put your accessories on it.

I thought I heard the military 6.2's had higher nickel blocks or some such thing. I can't say for sure, but I'd go for a military block and J code if you can get it. Shouldn't be too hard since lots of people want the heavy duty CUCV drivetrain without the diesel.