Stringer Upper Gear Case Interchange?

[TruckDrivingFool]

Short question will this work for my 18ss? Mine is a model# 990243s

I've noticed a slip every now and again and read that the usual suspects are the ball gears and the water pump shaft. Are the stringer intermediate and upper boxes all the same through the years and across the makes (elec. and mech-elec.)? I saw that one on Ebay and thought it might save the day for parts if mine kicks the bucket.

 

[Scott Danforth]

no, they are not all the same. why not replace your ball gears and the shafts on your existing outdrive?

 

[TruckDrivingFool]

Boat is 90 miles away and I wasn't smart enough to tear it apart and take care of it over the winter.

Depending one the shape, rebuilding parts from that one to have new parts on hand to swap out on a trip down was the next option.

 

[Scott Danforth]

you need a dial indicator and a bunch of other tools to rebuild the upper. you will also need a few shim packs. the ball gears are a maintenance item (I replaced mine every 4 years). the shaft replacement is because the design is flawed, and they all appear to fail.

 

[TruckDrivingFool]

Any idea what years I should look for to work on my 79?

 

[Scott Danforth]

1978-1980, or 1981 to 1984/85

 

[TruckDrivingFool]

Thanks Scott

 

[TruckDrivingFool]

I'm still searching for a spare and came across a v6 outdrive. Any ideas about how different the gearing would be for an 82' 3.8l complared to what my 4 cyl is backed by?

 

[TruckDrivingFool]

Best as i can figure mine is a 21:18 the v6 one is 21:20 any guesses how much and which way rpm would be effected?