Loctite or antiseize grease

ferdly1

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Recently I posted a question about proper torque values on a 1997 75 hp force. I was wanting the torque values for the bolts that hold the adapter plate to the engine and the adapter plate to the motor leg. I found the torque values although I think the torque is rather low for a 9/16 bolt holding an engine in place. The value is 22.5 ft lbs. I plan to torque them to 25 ft lbs. This leads to my next question. When I attempted to remove these bolts previously I ran into some problems with rusted bolts even had to drill one out (boy that was fun). Seeing as how the bolts were so tuff to get out, I thought I would use anti seize on bolts going back in. However my one area of concern is the torque of 25 ft lbs. Being that this is a two stroke motor which vibrates a lot, I am going to use medium strength loctite on bolts during reassembly so they dont vibrate lose. Right now my plan is to use loctite on bolts holding adapter plate to motor since i cant see the bolts once engine is installed. I will then use antiseize grease on bolts holding adapter plate to motor leg these are bolts I can see and get to if they come loose. This motor will be used in salt water. Is my thinking correct? I would appreciate any suggestions.
 

Chryslerman123

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You should not need loctite if you torque them to specification. Not sure about anti-seize, probably won't hurt though.
 

jerryjerry05

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Anti-seize is not a grease.
​It turns into permanent seize when you introduce it to salt water.
They don't mix well.
​The 25# is enough to not wiggle free.
How hard was it to remove them?
​You don't need lock tite.
​If your worried use a marine grease or ANY grease to coat the threads.(any grease is better than none. Bondo)

​As soon as you put it in salt water the corrosion starts and the screws will rust in place.
​I just broke down a 87 125 salt water motor and it didn't have 1 screw that came out easy.
I use grease on headbolts too.
 

Scott Danforth

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stainless and aluminum dont mix in a salt water environment.

if a fastener torque is 22.5#, going 25# is 10% over its recommended torque. torque values may be set to thread strength. long story short. if the torque value is 22.5#, I would suggest torquing it to 22.5#

if you want the bolts to come out, tef-gel, however that slippery stuff is a bit too slippery. Im a big fan of blue loctite
 

ferdly1

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Thanks thats exacly the input I wanted. So no antiseize. I have had good luck with the blu loctite. I use that on everything cars boats motorcycles. Just was unsure with saltwater. Someone asked how bad were the bolts. Couple of the bolts were rusted so bad I had to use an easyout. One bolt which had an allen head I had to drill out. It was almost against the motor. What a pain to remove. All stainless steel going back in 316 stainless. So if stainless reacts bad with aluminum what is another choice?
I was gonna order the bolts thru website but they wanted 5-7 bucks a bolt and they arent made of gold.
 

Scott Danforth

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Doesnt matter if the bolts are 316L or 18-8. Galvanic corrosion isnt indiscriminate
 

jerryjerry05

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Like Scott said: stainless in alum? Gonna have a reaction.
I just tore down 2 88/125s and have lots of bolts and nuts that are still usable?
​You pay postage they're yours free.
But Home Depot has a good selection of Stainless or even the good old one that rust.
 

dingbat

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Doesnt matter if the bolts are 316L or 18-8. Galvanic corrosion isnt indiscriminate
Big alloy (composition) differences between 316L and 18-8 stainless. Huge difference in corrison restance. 316L only on a boat
 

Scott Danforth

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They both cause galvanic corrosion when you add aluminum and salt. You can actually light a bulb as the voltage is about 1.5 volt. Add a bit of copper and you may as well put an eveready decal on it
 

gm280

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Jun 26, 2011
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I have noticed over the years that higher grade bolts don't rust as easily as the standard grades do. And at merely 22.5 ft/lbs, there are probably using standard grade bolts. So maybe use grade eight bolts could help resist corrosion. :noidea:
 
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