I think the hydro was phased in through the 86 model year.
Billybobf, I think he has had that for sale for awhile. Best ask for other pictures before driving over. Sure it is a short two hours but I think it looked worse for wear. Hard to remember them all. But you would be into 1. a new set of pistons and rings possibly. Maybe they are just coked up and not sealing well from that. 2. fixing the veg oil system or removing it. could he have just not flipped it back to diesel when he drove it last? 3. all the other general fix its that come with a 1985 diesel car.
Not much info in the ad which always makes me leery of them.
Got parts mostly installed on the WVO system this weekend. Waiting on fittings from Grainger.
I have 1st oversize pistons ready to go with about 2700 miles on them, Might even run the rings that are on them, might take a while for them to break in. and I have the boring bar to take it over.