Transom Assembly Repair Considerations

alldodge

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First sorry someone got me thinking about an ongoing issue and need to bounce it off more folks

Currently there are two methods to repair the steering pinion and seal. The Merc method drills a hole on each side and installs plastic plugs to reseal. The JR Marine method cuts out a section on the rear of the assembly and installs a stainless steel plate.

My thoughts:
Merc uses plastic plugs and while there is less room it doing the steering pin replacement, there is no issue with corrosion due to dissimilar metals.

JR uses a stainless steel plate and screws, and allows a bit more room it doing the pin replacement, there appears to be issues due to corrosion and dissimilar metals.

So after the JT repair, one needs to keep an eye on stainless and aluminum being bonded together. I am assuming these differences can cause some serious issues later.

These comments all come from the last few folks which have had issues with the upper assembly corroding and causing a hole in the upper transom assembly. My additional thoughts was that anyone which has their boat in salt water needs to remove the decal on top the transom assembly. This decal can hold the salt behind it, IF the decal becomes loose from the upper plate
 
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Scott Danforth

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aluminum and stainless dont play nice together. the JR marine kit needs a layer of plastic between the stainless and aluminum. I recommend UHMW tape on the back side of the plate as an isolator
 

alldodge

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aluminum and stainless dont play nice together. the JR marine kit needs a layer of plastic between the stainless and aluminum. I recommend UHMW tape on the back side of the plate as an isolator

Good point but what about the screws? Its my understanding is they are also stainless.

If an aluminum plate was used and aluminum rivets, I'm thinking this would help
 

Scott Danforth

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Stainless screws dipped in 5200 would be fine too. That would somewhat isolate the two metals
 

Bondo

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If an aluminum plate was used and aluminum rivets, I'm thinking this would help

Ayuh,.... 'n no reason to buy any "Kit",...

Epoxy, 'n glass is another option,....
 

muc

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When S.S. Screws go into aluminum

Above the waterline I recommend 1- Tef Gel. 2- Lanocote

Below the waterline- Perfectseal

When S.S. screws go thru aluminum it's best to use a plastic bushing

Trying to separate them electronically is important
 
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