Used DT25...poor performance, locked driveshaft bearing.

[MetrixSteve]

I recently purchased a 1990 DT25 oil injected outboard. First time out, 5 mph at WOT is all it would produce (engine is on a 15 Klamath aluminum). Mechanic thought it was over propped, changed to less pitch, only produced 1 mph more. Second time out, engine seized. He found "driveshaft bearing had locked up". He says he'll replace it, but my question is this: was bearing the reason for the poor performance initially? Compression check before I purchased was over 100 psi per cylinder, and the engine revved nicely in neutral, just not in gear. Thank you in advance for you responses.

 

[TwoRivers]

I recently purchased a 1990 DT25 oil injected outboard. First time out, 5 mph at WOT is all it would produce (engine is on a 15 Klamath aluminum). Mechanic thought it was over propped, changed to less pitch, only produced 1 mph more. Second time out, engine seized. He found "driveshaft bearing had locked up". He says he'll replace it, but my question is this: was bearing the reason for the poor performance initially? Compression check before I purchased was over 100 psi per cylinder, and the engine revved nicely in neutral, just not in gear. Thank you in advance for you responses.

Welcome to the forum.
That could definitely slow you down. Check compression again before putting too much cash into repairs.
good luck
rob

 

[99yam40]

only drive shaft bearing I know about is in the lower unit
dropping the lower should free up the motor if that is the problem,
and it that locked up I am sure the metal from it got into the other bearings and gears

 

[MetrixSteve]

Driveshaft bearing and propshaft seal replaced. Engine starts and runs nicely at shop, however, 1st trip out it will only produce 5 mph and has a slight miss. Putting boat on the trailer, it wont move boat 6 inches at WOT. Shop is buying back engine.