mercruiser 260 hp motor mount to boat bolts?

kershawD

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what size type and length of hardware is used to attach motor mounts to the boat?
 

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kenny nunez

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Stainless steel 3/8” X 3” with stainless washers is what I have seen and used the most of. Also try to inject some 3M #5200 sealer in the pre drilled hole before installing the lag bolt.
 

alldodge

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Agree, in most cases its lag bolts, and size depends on how much wood is available to fasten into. Many have been 3/8, but would use the largest that would fit in the slot, and length depends on depth available

Others use bolt and nuts when plates are mounted and thru bolts used in stringers
 

Bondo

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but would use the largest that would fit in the slot, and length depends on depth available

Ayuh,..... 1/2" galvanized lags with washers,....... could go ssteel,.....

The condition of the wood is more critical,.....
 

kershawD

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thanks . I found 3/8 x 4'' SS lag bolts and washers at my local big box. 3/8 x 4'' was the largest they carry. the stringers and wood is in excellent shape for a 1978 boat.
 

Bondo

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Ayuh,..... I hope the motor mount wood is more than 4" deep,....

In some hulls, those 4" bolts would be stickin' through the bottom of the hull an inch or so,.....
 

Scott06

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X2 I don't think mine were more than 2" long when I swapped motors
 
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