What do you recommend

[elkhunter338]

Since I am a starcraft guy and we tend to help each other out I have a question on replacement of a thermostate on an outboard. The Johnson/ section guys gave no help.
What I have is a 25hp johnson 1995 that I need to replace the thermostate. it is running cold.

My question is what type of substance should I put on the bolts that bolt the thermostate plate into place. what it has is grade 5 steel bolts into alum., they all came out ok, but have some corrosion.
What does the manual recommend or what in your experience works good so the bolts will come out again.

I was thinking marine grease, high temp anti-seize, or teflon pipe sealer (paste). I am leaning towards using marine wheel bearing grease.

Thanks

 

[Pugetsound]

Re: What do you recommend

I was told once to use Lock-tight as it will hold and make for easy removal. I have used it with no problem. I think the Grease may become hot and stick to the threads. Good spot for adivse.

 

[fshngho]

Re: What do you recommend

If you are concerned about removing them again one day, there is a product called Never Seize. Its a graphite mixture that you apply to any bolt/nut and it will never freeze up.
Dale

 

[ezmobee]

Re: What do you recommend

Pretty sure there are different colors of Loc-tite for different purposes. I do know NOT to use the red one for anything you may someday want to remove.

 

[Gnarly]

Re: What do you recommend

Mastinox, its carcinogenic and nasty yellow stuff but it works. If you have an outfit operating eurocopter helicopters near you head on down and see if you can scrounge some. Wear gloves when applying and it can be thinned if nescessary with MEK.
If you dont want to go that route good old alox works ok but nothing beats mastinox for corrosion prevention.

 

[dozerII]

Re: What do you recommend

There is a loctite brand anti sieze /never sieze made speciffcly for steal to aluminum. I bought mine at a bolt supply house. works great.

Glen

 

[Bob Gilvary]

Re: What do you recommend

A simple solution to all this is to use Starbrite brand antisieze. It's copper colored due to the copper in it I guess. Looks like copper metal flake, anyway.

I've used it for years in repairing marine engines.

I made the mistake of using a grey colored antisieze once, never again, for marine use.

All of my work is in the most extreme marine conditions, SALTWATER. For those of us in the south, don't think that just because you use your boat in so called fresh water, you're safe. These black water rivers have more minerals to cause electrolysis than salt water. The worste I've ever seen was in the Butler chain of lakes in Fl.

 

[Gnarly]

Re: What do you recommend

Im not trying to be a smartass but adding copper to carbon steel bolting it into an aluminum housing and exposing it to sea water doesnt sound like a good idea to me , the galvanic loser is the aluminum housing. I could be wrong, its happened before but the multi million dollar equiptment I work on every day copper antiseize isnt even allowed into the hangar mostly due to hydrogen embrittlement issues.
the standard nickel antiseize on stainless fastners and molydisulphide based grease on most dry splines that require lubrication ( sundstrand spline grease) different greases for oscillating and non oscillating bearings etc. Tectyl grade 1 and 2 are used for corrosion prevention on some fastners (alox mix) and Mastinox , I have never seen mastinox fail to protect a fastner from corrosion, cant get it apart at minus 30 but it'll protect it all right and last a whole lot better than tectyl.
locktite works and might even be a good choice in this application , 242 (blue) should be just about right with cad plated bolts if you cant find the mastinox or tectyl, dont forget to use a sacrificial aluminum washer under the bolt head.

 

[Gnarly]

Re: What do you recommend

Im not trying to be a smartass but adding copper to carbon steel bolting it into an aluminum housing and exposing it to sea water doesnt sound like a good idea to me , the galvanic loser is the aluminum housing. I could be wrong, its happened before but the multi million dollar equiptment I work on every day copper antiseize isnt even allowed into the hangar mostly due to hydrogen embrittlement issues.
the standard nickel antiseize on stainless fastners and molydisulphide based grease on most dry splines that require lubrication ( sundstrand spline grease) different greases for oscillating and non oscillating bearings etc. Tectyl grade 1 and 2 are used for corrosion prevention on some fastners (alox mix) and Mastinox , I have never seen mastinox fail to protect a fastner from corrosion, cant get it apart at minus 30 but it'll protect it all right and last a whole lot better than tectyl.
locktite works and might even be a good choice in this application , 242 (blue) should be just about right with cad plated bolts if you cant find the mastinox or tectyl, dont forget to use a sacrificial aluminum washer under the bolt head.

http://www.onepetro.org/mslib/servlet/onepetropreview?id=NACE-03017&soc=NACE

 

[Bob Gilvary]

Re: What do you recommend

All I can say is, I used your type of antisieze on a prop shaft in salt water, then had to burn the prop off a few months later. This antisieze was what was used at Kennedy Space Center, in that salt air invironment

Starbrite's antisieze is made specificly for marine aplication.

Anybody ever notice bottom paint turning green? Copper in the paint. There's no strength in copper corrossion and as it self sacrifices and comes off, so does the barnicles. This might or might not mean something.

What I am sure of is, I'll take experience over education every time.

 

[Bob_VT]

Re: What do you recommend

Clean the bolts...... I will bet good money that they are not steel but stainless steel. A few drop or two of locktite on the end and a smear of any wheel bearing grease by the head of the bolt.

Be careful with never-seize which contains metal particles and yes can cause a reaction.

 

[elkhunter338]

Re: What do you recommend

Thanks for the info. Sounds like I should stay away from never seize unless it is marine anti-seize.
Mastinox is not available in my area, or at least I cannot find any.
I will probably go with marine spline grease or marine wheel bearing grease.
For a water pump housing I am still unsure if blue locktight is needed. I know stay away from the red stuff.
The bolts are steel, grade 5 head markings, magnet sticks very well, but they do look like they are plated.
Thanks again for the information and I have heard other threads in the past warning of not using automotive grey or copper anti-seize for marine application.
I got so much more information on our starcraft site than on the Johnson outboard posting.

 

[Bob Gilvary]

Re: What do you recommend

A little bit of heat from a hand held propane torch, applied to a bolt with red locktite will break it loose.