1989 Force 50 507Y9B lower unit nightmare

Icr242005

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Aug 14, 2017
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First thing before I get started, any help at all would be greatly appreciated. I keep getting water in lower unit. So I tore the lower unit apart and have several question. (1)Does the cup on the water pump seal go up toward the motor or down toward the gear case? (2) The seal under the water pump, does the cup go up toward the water pump or down toward the gears in the lower unit? (3) Shift rod leakage seal, metal part up toward motor or down in the case. (4) should there be any end play in the prop shaft. If to much end play and where does the shims go? (5) Does anyone know how much clearance should be on the gear bearing/bushing? I currently have 3-5 thousands. (6) Should the drive shaft be perfectly straight or in there a run out tolerance? I know this is a lot but if anyone knows any of this, please help me out.
 
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GA_Boater

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May 24, 2011
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49,038
I would say how to orient the seals, but I'm not familiar with Force motors and don't want to give you bad info.

I can help of the selling section - We don't have one in the forum, in fact buying and selling isn't permitted. However, the store does have a pay classified section. Click on Boats For Sale on top of the page.
 

jerryjerry05

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May 7, 2008
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18,084
I believe the open part(might have a spring) of the seal goes away from the housing
#1The top seal on the pump housing, it really doesn't matter.
#2 Up
#3 Metal up. Make sure the housing is spotless and any build up is gone.
#4 No side to side but it might push in.
#5 The shims are usually under bearing cup in the front.
#6 The shaft when running should have no wobble, and run true as you look at it.
They say there can be a bit out of true but I've never seen one last that isn't absolutely straight .
 

Icr242005

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Aug 14, 2017
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Thank you, Jerry this is a big help. might as well cover the last seal for someone else that might look at this post. Prop shaft seal, cup side (or spring) facing the prop or gears ? I am a small block Chevy guy and on the seals for them you want the cup facing in so the crank case pressure will help push seal lip in and help seal it
 

jerryjerry05

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May 7, 2008
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You should be able to see the old one as you take it out.
The book says spring out from the housing.
 

Icr242005

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Aug 14, 2017
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36
Jerry, I could but I don't trust last person to put it together. I have 3 lower units, 1 come tore apart and the other 2 have them going in different way.
 
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