2005 135 Optimax: Owned since brand new, never had trouble. Backing off a sand bar - Hangs up in reverse. The throttle will move into the forward position, but clearly the lower unit is stuck in reverse.
Take to shop: Mechanic says: Reverse gear has welded itself to the output shaft - never seen this happen before. Replaces output shaft and gear set (cha-ching $800). Boat runs like a top, everything is fine.... for about 5 hours of run time.
Backing off a sandbar... Hangs up in reverse. Shifts just fine, except that the lower unit is staying in reverse. Take to shop: Mechanic says: Reverse gear has welded itself to the output shaft (again!) You must be some kind of throttle jockey with this rascal. Replaces output shaft, gear set AND bearings. (Cha-Ching $1200). Boat runs like a top....everything is fine.... for maybe 5 hours of run time. CapnDean then gets aboard this vessel, and goes to tug a fellow boater off a sand bar (in reverse of course). Boat loses the ability to shift from reverse to forward. Shifter works fine, throttle works fine... but the lower unit is stuck in reverse. Take to shop: Hmmm reverse gear is welded itself to output shaft AGAIN.
CapnDean orders a brand new (SEI knockoff aftermarket lower unit) Installs it and puts 5 hours of break-in run time on it with no issues. Changes gear lube at 5 hours. No shavings no worries. Deliver the boat back to the owner. Owner takes the boat, launches it and says HOLY SMOKES it started in gear and tried to drive itself back onto the trailer. Owner takes it to mechanic, mechanic adjusts shift linkage says everything checks out just fine.
Backing off a sandbar last night, it has hung up in reverse AGAIN. I have not been inside the SEI gearbox....it will go back to the manufacturer because it has a 3 year warranty. I suspect however that we will learn that the reverse gear has again welded itself to the output shaft.
My question for the rest of the world: What the heck can the top half of a motor be doing to the lower unit, that is causing it to seize into reverse? Obviously the problem continues to occur despite replacing the entire lower unit.
I can confirm that at no point in time has their been any issue getting the motor to shift properly from fwd to neutral to reverse PRIOR to the seizing issue. It's not like the linkage is out of whack and the motor isn't shifting all the way into gear or anything like that. As far as the owner being a throttle jockey? That's a non-issue as well, it isnt being used any different than it was the first 10 years of it's life..... For the life of me I am stumped.
What can be wrong with the top or the shift linkage.....that would cause this motor to weld revers gear to the output shaft 4 separate times?
Take to shop: Mechanic says: Reverse gear has welded itself to the output shaft - never seen this happen before. Replaces output shaft and gear set (cha-ching $800). Boat runs like a top, everything is fine.... for about 5 hours of run time.
Backing off a sandbar... Hangs up in reverse. Shifts just fine, except that the lower unit is staying in reverse. Take to shop: Mechanic says: Reverse gear has welded itself to the output shaft (again!) You must be some kind of throttle jockey with this rascal. Replaces output shaft, gear set AND bearings. (Cha-Ching $1200). Boat runs like a top....everything is fine.... for maybe 5 hours of run time. CapnDean then gets aboard this vessel, and goes to tug a fellow boater off a sand bar (in reverse of course). Boat loses the ability to shift from reverse to forward. Shifter works fine, throttle works fine... but the lower unit is stuck in reverse. Take to shop: Hmmm reverse gear is welded itself to output shaft AGAIN.
CapnDean orders a brand new (SEI knockoff aftermarket lower unit) Installs it and puts 5 hours of break-in run time on it with no issues. Changes gear lube at 5 hours. No shavings no worries. Deliver the boat back to the owner. Owner takes the boat, launches it and says HOLY SMOKES it started in gear and tried to drive itself back onto the trailer. Owner takes it to mechanic, mechanic adjusts shift linkage says everything checks out just fine.
Backing off a sandbar last night, it has hung up in reverse AGAIN. I have not been inside the SEI gearbox....it will go back to the manufacturer because it has a 3 year warranty. I suspect however that we will learn that the reverse gear has again welded itself to the output shaft.
My question for the rest of the world: What the heck can the top half of a motor be doing to the lower unit, that is causing it to seize into reverse? Obviously the problem continues to occur despite replacing the entire lower unit.
I can confirm that at no point in time has their been any issue getting the motor to shift properly from fwd to neutral to reverse PRIOR to the seizing issue. It's not like the linkage is out of whack and the motor isn't shifting all the way into gear or anything like that. As far as the owner being a throttle jockey? That's a non-issue as well, it isnt being used any different than it was the first 10 years of it's life..... For the life of me I am stumped.
What can be wrong with the top or the shift linkage.....that would cause this motor to weld revers gear to the output shaft 4 separate times?
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