Driveshaft stuck in flywheel OMC 85 hp- advice?

[ledgefinder]

I have two of these on some old engines I'm messing with - a 1969 OMC 85 and a 1971 Merc 80. One needs an impeller (run in 1969, then sat in a shed for 33 years...), one has a leaky shift seal.<br /><br />Any words of wisdom here? I know I can burn through the exhaust housing & shaft with a torch - just wondering if there are any less-drastic measures worth wasting time with first. Does running the motor for a bit first help?. Doing chin-ups on the propshaft? Running the engine a bit in forward and reverse, in the water with a prop on? <br /><br />I can get replacement midsections for either engine easily. If I do torch an access panel through the midsection, any tricks on getting the shaft out without cutting it? Thinking heat, PBBlaster & patience. Both lower units are nice so I hate to start sawing things up...<br /><br />I know ultimate solution...only work on motors from 1990s, right?

 

[sparkroost]

Re: Driveshaft stuck in flywheel OMC 85 hp- advice?

you could cut 2 access windows 180 deg apart and weld a goober on each side of the shaft, then use 2 pry bars. When you are done, grind off the goobers and re-assemble.<br /><br />If you can get access to the bolts holding the driveshat in place, you could remove the drive shaft from the lower unit(have to remove the prop shaft and pinion gear). Once you get the lower unit off you could make a slide hammer using the driveshaft and a heavy enough socket with a through hole to fit around the shaft. Use the old pinion nut to secure a stop to the bottom and slide hammer away.<br /><br />3rd choice, you could put some dynomite in there and detonate it

 

[sparkroost]

Re: Driveshaft stuck in flywheel OMC 85 hp- advice?

You might even be able to remove the cowling, lower trim pieces and un bolt the leg from the adapter plate. Then pry from both sides at the same time.