Mystery hole evinrude 70

maineiac5586

Master Chief Petty Officer
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Feb 14, 2009
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801
So I am breaking down my 1986 evinrude 70 hp and found this hole. I can see threads in there. It's at the bolt that bolts the cases together. Very confused. I applied air pressure to the hole and don't hear it coming out anywhere. Anybody have a clue what is going on here?
 

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maineiac5586

Master Chief Petty Officer
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Feb 14, 2009
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It runs good with great compression and no noise? It's almost like it was drilled too deep when it was made? No air escapes that hole when running and it was dry in the hole no oil or anything
 

racerone

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Dec 28, 2013
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That is absolutely normal.-----It is the bolt hole to hold the block together !-----Once you have this motor apart you will see all this simplicity.
 

racerone

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Dec 28, 2013
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Maybe stick a wee pin in the hole and turn that bolt.-----See what happens.
 

maineiac5586

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Maybe stick a wee pin in the hole and turn that bolt.-----See what happens.
I'm sorry I'm not sure what you mean by bolt hole to hold block together or wee pin? Are you being sarcastic or serious?
 

racerone

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It is a bolt hole I believe.----One of bolts to hold the block together.---I will leave you alone now.
 

maineiac5586

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No bolt can go into that hole. It is actually at the bottom of the bolt hole from the bolt that goes horizontal seen in last picture. Just seems strange to me
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Have you guys seen something like this before?

As stated above many times

The hole is what happens when the drill at the factory drilled thru the casting. The threads are a bit shorter. The bolt is on the other side of the casting split

If it bothers you, shove a bit of bubble gum in the hole, or epoxy, or rtv
 

racerone

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I bought 21 of those 3 cylinder motors at auction one time.----So , yes I have seen it on everyone of them.----I assume you are baffled by your first motor ----Sorry to be blunt.
 

maineiac5586

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Feb 14, 2009
Messages
801
I bought 21 of those 3 cylinder motors at auction one time.----So , yes I have seen it on everyone of them.----I assume you are baffled by your first motor ----Sorry to be blunt.
Lol it's OK. Yes first time seeing this. Thanks for clarification
 
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