LU bearing and seal adhesive or sealant?

[baytonemus]

I'm going to apologize for reposting this question from another thread. I don't know if forum rules permit that or not.

On the matter of sealants in general, I think I've read 50 threads on this topic but, predictably, there are a number of different opinions. The manual doesn't say anything about using any adhesive or sealer when reinstalling these...

- driveshaft oil seal
- driveshaft needle bearing
- prop shaft seal
- shift rod bushing

However, these motors weren't 40-50 years old when the manuals were written, and I know that some people including OB motor shops ALWAYS use something like an RTV when they put these things back together.

So, I'm not sure if I should or not. Recommendations including specific products would be welcome. Thanks!

 

[Daviet]

Re: LU bearing and seal adhesive or sealant?

On the items you mentioned, i don't use any type of sealer. But as you stated there many different views on the subject and I am sure you will get many different ansewers.

 

[lindy46]

Re: LU bearing and seal adhesive or sealant?

I only use sealant on the skeg/spaghetti seal and around the large o-ring on the prop shaft bushing.

 

[baytonemus]

Re: LU bearing and seal adhesive or sealant?

I only use sealant on the skeg/spaghetti seal and around the large o-ring on the prop shaft bushing.

Plus on the screws when you reassembly, I would assume???

 

[bktheking]

Re: LU bearing and seal adhesive or sealant?

That's what OMC suggests when reassembling, threads of the screws as well.

 

[Kit_B]

Re: LU bearing and seal adhesive or sealant?

Ha...I didn't even see this post, when I posted mine.

That spaghetti seal seems like a piece of junk.
Does anyone make something that fits the groove more accurately?

Are there any recommendations on how to hold it in place, as you reassemble?

 

[baytonemus]

Re: LU bearing and seal adhesive or sealant?

Ha...I didn't even see this post, when I posted mine.

That spaghetti seal seems like a piece of junk.
Does anyone make something that fits the groove more accurately?

Are there any recommendations on how to hold it in place, as you reassemble?

You need 3M #847 (available from Grainger), although some people use Permatex #2.

This thread is drifting. Can we stick to my original inquiry about whether or not to use a sealant or adhesive around the bearings and seals? Thanks.

 

[Tim Frank]

Re: LU bearing and seal adhesive or sealant?

I just did my 6 hp e/rude , 1975....the manual suggested sealant in the bore of all seals....and the screws. We discussed that in the other thread, too.

I suspect that you are on to something when you point out the vintage.
Even in the 10 years between our respective motors' fab date, sealant technology advanced a long way plus in some ways the machining and casting quality dropped off somewhat.

I know that the technology in my 1990 e/ride 8 hp is way ahead of the 1975 6 HP, but the quality of construction sure isn't.

 

[Kit_B]

Re: LU bearing and seal adhesive or sealant?

You need 3M #847 (available from Grainger), although some people use Permatex #2.

This thread is drifting. Can we stick to my original inquiry about whether or not to use a sealant or adhesive around the bearings and seals? Thanks.

Sorry...Didn't mean to hyjack.

 

[baytonemus]

Re: LU bearing and seal adhesive or sealant?

Sorry...Didn't mean to hyjack.

No sweat. I've just been trying to get a range of input on this particular issue for awhile.

 

[baytonemus]

Re: LU bearing and seal adhesive or sealant?

I just did my 6 hp e/rude , 1975....the manual suggested sealant in the bore of all seals....and the screws. We discussed that in the other thread, too.

I suspect that you are on to something when you point out the vintage.
Even in the 10 years between our respective motors' fab date, sealant technology advanced a long way plus in some ways the machining and casting quality dropped off somewhat.

I know that the technology in my 1990 e/ride 8 hp is way ahead of the 1975 6 HP, but the quality of construction sure isn't.

Thanks again for your input, Tim. I think you and I were the only ones keeping that other thread alive so I thought I'd try and jump start this with a more specific topic.

 

[baytonemus]

Re: LU bearing and seal adhesive or sealant?

I spent some time yesterday investigating this and made a call to Permatex technical support to see what they would suggest. The guy I spoke with recommended Permatex 1372 High-Temp Form-a-Gasket, which he said would be easier to remove than a silicone product. Of course, no one in my city carries it so I couldn't get it until sometime next week. Plus, it's almost $14 a tube. Seems like overkill, honestly.

After talking with the guy that runs the machine shop that I use, I've decided on Blue Loctite which I already have (the Dynatex version of it, actually). As always, I'm open to hearing that I'm an idiot, but that's the plan.

 

[Tim Frank]

Re: LU bearing and seal adhesive or sealant?

Definitely not an idiot, but you may be over-thinking this a bit.
Doing the job carefully and skillfully will be 95% of the success factor....choice of sealant 5% or less....and if you pick something reasonable, you'd achieve 95% of that last 5%.

If I were you, I'd use whatever was the closest match that I had on the shelf, and get back on the water....

 

[baytonemus]

Re: LU bearing and seal adhesive or sealant?

Definitely not an idiot, but you may be over-thinking this a bit.
Doing the job carefully and skillfully will be 95% of the success factor....choice of sealant 5% or less....and if you pick something reasonable, you'd achieve 95% of that last 5%.

If I were you, I'd use whatever was the closest match that I had on the shelf, and get back on the water....

You may be right, but when I'm learning how to do something that I've never done before, I want to be thorough so that I actually understand the issues and principles that are involved. The way I approach it this time is probably going to inform the way I go about it in the future. Plus, this needs to be reversible. If I choose the wrong product it may be very difficult or even impossible to replace these bearings and seals in the future. Considering that I'm already departing from recommended procedures, I'm going to be pretty deliberate.

Thanks.

 

[metriccrescentwrench]

Re: LU bearing and seal adhesive or sealant?


Get a shop manual and do whatever it says. The specific items you listed (driveshaft oil seal, driveshaft needle bearing, prop shaft seal, shift rod bushing) aren't supposed to have any sealant on them (at least on the two outboard engines I have). I learned the hard way when I was racing go-carts many years ago that putting RTV where it didn't belong can really screw things up.

 

[baytonemus]

Re: LU bearing and seal adhesive or sealant?

Get a shop manual and do whatever it says. The specific items you listed (driveshaft oil seal, driveshaft needle bearing, prop shaft seal, shift rod bushing) aren't supposed to have any sealant on them (at least on the two outboard engines I have). I learned the hard way when I was racing go-carts many years ago that putting RTV where it didn't belong can really screw things up.

I do have the manual and I basically acknowledged what you're saying in my original post. The issue is that, although a nice new bearing or seal in a brand new bore or retainer isn't going to leak, that doesn't mean that the same thing will be true in a 50-year-old OB. Build up of crud, improper removal and scoring/gouging, possible use of other non-specified adhesives and sealants by previous owners all factor in here.

Also, I'm not opting for silicone (RTV). Out of curiosity, though, what do you think I might screw up by using this thread lock product? It's made to be removable.