Originally Posted by rjrcmr03
Yes turning the coupling turns the input shaft and turns the flywheel which turns the crankshaft all this with the engine off. The other trans no problem some resistance but so very little.
There is good news and there is bad news.
The good news is you have air in your lungs and you have a nice boat.
The bad news is your transmission is hosed and you've got to yank your boat, yank your engine / transmission assembly, disassemble your transmission and fix the problem(s).
On a good transmission the input shaft is powered from the engine and the control block directs the 312-377 PSI to push the input shaft to compress the clutch pack A (near the engine) to cause the output to rotate opposite to the engine, or to compress clutch pack B (away from the engine) to cause the output to rotate the same as the engine.
Clutch pack A directs the torque to the output shaft. Clutch pack B directs the torque to the intermediate shaft, then to the output shaft.
It sounds like your problem is that one clutch pack is always / permanently engaged. Then when shifting / moving the input shaft to engage the other clutch pack, the transmission stops the engine from rotating.
The path for the binding torque is input shaft => clutch pack A => => output shaft => intermediate shaft => clutch pack B => input shaft (opposite direction).
IMO, the BIG problem is that all these parts have been subjected to the very, very abnormal shock forces of stopping a big block V8.
IMO, all these parts should all be Magnafluxed, even if they look okay, because they have been abused and some may / will fail.
Download the Operating Manual and the Transmission Manual for your Hurth
Please post images
of the failed parts.