Reverse roll start

will an engine be destroyed if it is roll started in reverse, that is wheels rolling forward and transmission in reverse?

It won’t start when pushed forward with the transmission in reverse. It would be difficult to push forward while in reverse, but if continuously forced by a vehicle pushing it engine damage would soon result. The timing system isn’t capable of sustained reverse rotation and something would likely fail there. I would also suspect damage to motor mounts and the drive train if pushed very far in reverse.

it was for a second or two, enough for a cloud of smoke to come out the air intake. the car wouldnt start before this happened, and still wont, though it did 2 years ago when it was parked. when roll started in the normal fashion now the engine will start, but the rpms will slow down eventually stopping.

I believe the distributor turns off the camshaft. If so, turn the crankshaft to the top dead center position and look at the distributor rotor position. It should be very nearly in line with the #1 or #4 plug contact on the distributor cap. It might not be much trouble to pull the timing cover off to know for sure. It is very likely to be out of time.

I thought this was a diesel.

it is a 1986 jetta 1.6l turbo diesel

I’ve heard of diesels can be roll started in reverse. But I don’t know if their oil pumps work in the reverse direction.

No, it won’t destroy the engine. The engine won’t start or run in the wrong direction. If the car sat for two years, I’d say the problem keeping it running is from that, not the push-start in reverse.

You’re working with a 24-year-old car. Try replacing the fuel filter. Good luck.