Two+ Year Tef-Gel Experiment Complete !!!!

Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
Hi All,

As promised a loooooong time ago I am reporting on the use of Tef-Gel on the prop shaft coupling. After two+ years my coupling came off 100% rust free and with all the original tolerances intact and not destroyed by a thin layer of rust.

Prior to installation I coated the inside of the coupling, the key way, the key and the shaft with a liberal amount of Tef-Gel.. While most of it was wiped away by the very tight tolerances when assembling it the anti-corrosion abilities were unharmed. After removal both the shaft and inside of the coupling have a think feeling, extra tacky layer of protective Tef-Gel.

Mike the manager at my prop shop thought for sure the Tef-Gel would have been totally wiped away and would add noting but it survived. The nice thing about Tef-Gel is that unlike Anti-Seize products that contain graphite or metals it does not add to galvanic corrosion issues.. It also works very, very well as a rust inhibitor..

My coupling came off like it was new with NO penetrating oil and only two bolts with my gear/hub puller.

On my last boat, which was brand new, I ran it for less than three months then hauled to change to a PSS. In just three months of use the coupling was already rusted on!!

Tef-Gel works!!!

WARNING: It should be noted that any sort of lube is advised against in a straight coupling. I know this and still decided the risk was worth it on my own boat. I have seen no odd wear to my key or set screws BUT my coupling was PROFESSIONALLY fitted to a light press fit tolerance.

After two plus years it came right off:

No RUST!

The Shaft:

Better Lighting Showing NO RUST!!






This photo shows NO Tef-Gel after just three months (note the rust adhered to the shaft that broke off the internal surface of the coupling):

__________________
 

Ross

.
Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
Re: You are subscribed to this thread Two+ Year Tef-Gel Experiment Complete !!!!

Looks pretty convincing to me. I guess that pays for the tube of tef gel in just one shot.
 
Oct 22, 2008
3,502
- Telstar 28 Buzzards Bay
Re: You are subscribed to this thread Two+ Year Tef-Gel Experiment Complete !!!!

nicely done.
 
Jul 1, 1998
3,062
Hunter Legend 35 Poulsbo/Semiahmoo WA
Same shaft coupling?

You mentioned that the first shaft coupling (the rusty one) was on the "first" boat but the second shaft coupling (the clean and good looking one) was, I guess, on the second boat, so my question is "are the shaft couplings different?"

And, if they are different, how do you be assured they have the same metalic composition?

Another question, being unpainted, could the first one have had some amount of salt water on it where as the second one, no salt water?

Other than that, looks like another good test write-up. Those are some really good looking photos.
 
Oct 22, 2008
3,502
- Telstar 28 Buzzards Bay
Re: You are subscribed to this thread Two+ Year Tef-Gel Experiment Complete !!!!

John—

The surface corrosion isn't the problem. It was the corrosion between the coupler and the shaft that was probably the real culprit. When steel rusts, it expands about 10%... and a 10% expansion in a tight tolerance piece like a shaft coupler makes it effectively un-removable.
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
You mentioned that the first shaft coupling (the rusty one) was on the "first" boat but the second shaft coupling (the clean and good looking one) was, I guess, on the second boat, so my question is "are the shaft couplings different?"

And, if they are different, how do you be assured they have the same metalic composition?

Another question, being unpainted, could the first one have had some amount of salt water on it where as the second one, no salt water?

Other than that, looks like another good test write-up. Those are some really good looking photos.
John,

The couplings are the same exact part number only one was initially painted and the other was not. Even the painted one got a little banged up during install and suffered surface rust. Both couplings were in similar installations & both had dry bilges and PSS shaft seals though the first one spent three months with Gore GFO before I switched over to a PSS. 90% boat bilge humidity will do stange things to unprotected steel...

The rust I'm referring to is between the stainless shaft and the inside of the coupling. I could really care less about the exterior. This fit tolerance, between shaft & coupling, is a machined tolerance out to the ten thousandths of an inch so any rust can destroy the fit and make for a loose fit which then creates wear due to allowable movement. Most often a used coupling is thrown away because it can't be re-used. Many times shafts are cut and destroyed because the coupling refuses to come off. This ads a HUGE expense to a simple task like replacing the shaft log hose. $12.00 worth of new stuffing box hose and $800.00 worth of shafting! A little Tef-Gel can help eliminate this..

Having been the grunt at the boat yard, when I was much younger, who was small enough to do jobs like alignments, repacking of stuffing boxes and shaft replacements I have seen hundreds of couplings thrown away due to a thin layer of rust which in turn blew out the tolerance.

This will only be the second coupling I have ever re-used thanks to Tef-Gel..
 

NYSail

.
Jan 6, 2006
3,048
Beneteau 423 Mt. Sinai, NY
I also have used this on my coupling 3 years ago. Removed it this year with no problem...still looks new. I also used this when installing my prop 3 years ago. The yard pulled my prop at haul-out (another story) and it slid right off. They were confused as they said they were getting ready to attached the prop remover.

The stuff works great!!
 

BobM

.
Jun 10, 2004
3,269
S2 9.2A Winthrop, MA
Sold. I literally just bought some. It would be worth it just to do the prop and the coupling, both of which were lots of fun to deal with last spring.
 
Jun 19, 2004
512
Catalina 387 Hull # 24 Port Charlotte, Florida
Thanks Again Maine Sail

For sharing this with us. I do have a question about my observation, yet don't want it to turn into a thread drift.

However, if you would not mind please, could you provide a bit of commentary about the use or non-use of a "Shaft Saver" or "Torque Limiter" since I notice what seems to be a direct connection between your transmission and the shaft coupler.

I have heard that it is often safe practice to have a device in-line to prevent damage should something get "tangled" up on the prop to cause everything to lock up. What are your thoughts about these devices?

I have to get some of this Tef-Gel. I would suspect that this has a wide spread application? Can it be used on exhaust systems that are exposed to high temperatures?

Thanks again for sharing your knowledge and experiences with us once again :dance:
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
However, if you would not mind please, could you provide a bit of commentary about the use or non-use of a "Shaft Saver" or "Torque Limiter" since I notice what seems to be a direct connection between your transmission and the shaft coupler.
I would have one in a heart beat, have had them on past boats but they do not work with a v-drive and nobody makes one that will work with my tranny. Also it is not just as simple as sliding one in as the prop shaft should not hang out beyond the strut any more than the diameter of the shaft. Adding a Drive saver can cause shaft whip if you did not build the shaft and cut it at the right length to compensate for the flexible coupling. In essence adding a flexible coupling to a properly fitted shaft will result in an improperly fitted shaft..
 
B

briangalton@shaw.ca

Re: Tef-Gel

Hi All,

As promised a loooooong time ago I am reporting on the use of Tef-Gel on the prop shaft coupling. After two+ years my coupling came off 100% rust free and with all the original tolerances intact and not destroyed by a thin layer of rust.

Prior to installation I coated the inside of the coupling, the key way, the key and the shaft with a liberal amount of Tef-Gel.. While most of it was wiped away by the very tight tolerances when assembling it the anti-corrosion abilities were unharmed. After removal both the shaft and inside of the coupling have a think feeling, extra tacky layer of protective Tef-Gel.

Mike the manager at my prop shop thought for sure the Tef-Gel would have been totally wiped away and would add noting but it survived. The nice thing about Tef-Gel is that unlike Anti-Seize products that contain graphite or metals it does not add to galvanic corrosion issues.. It also works very, very well as a rust inhibitor..

My coupling came off like it was new with NO penetrating oil and only two bolts with my gear/hub puller.

On my last boat, which was brand new, I ran it for less than three months then hauled to change to a PSS. In just three months of use the coupling was already rusted on!!

Tef-Gel works!!!
Hi,
I have just come across your posts re Tef-Gel. I am unfamiliar with this product and would like the manufacturer's name and address.
Many thanks,
Brian Galton
briangalton at shaw.ca
 
Oct 22, 2008
3,502
- Telstar 28 Buzzards Bay
Brian—

TefGel's website.

Ultra Safety Systems, Inc.
1601 Hill Avenue
Mangonia Park, FL. 33407

Phone: 561-845-1086
Fax : 561-844-8566
Toll Free: 800-433-Boat(2628)
Email: tg {at} tef-gel {dot} com

:soapbox:
BTW, Brian, there's this website called Google. It is an internet search engine. It is located HERE.

It allows you to search for information on the internet... if you type something into the box and then hit the search button, it comes up with likely results for that search term. Google is your friend... you might want to learn to use it. :doh:

Also, I would highly recommend you not post your e-mail address in machine readable form unless you like getting a lot of spam.:doh:

Hi,
I have just come across your posts re Tef-Gel. I am unfamiliar with this product and would like the manufacturer's name and address.
Many thanks,
Brian Galton
briangalton@shaw.ca
:lame:
 

NYSail

.
Jan 6, 2006
3,048
Beneteau 423 Mt. Sinai, NY
Re: Thanks Again Maine Sail

I have a shaft saver on my boat....when I bought her there was one in place, however I pulled the shaft and had it all checked by a prop shop for trueness (and a new coupling...prior owner did not use tefgell). The shop asked the question about distance from strut to prop and would cut if needed. Also, the new shaft saver I got had to be "fitted" to my shaft as part of the trueing up process. I love having it for the protection aspect....Had a friend who did not have one that broke his bell housing and a mount after he hit an object under water.

Though I have to add a jumper cable between the coupling as the shaft is islolated from the grounding when you add the shaft saver. I need the shaft zincs to prevent gavanic corrosion.....my pearson P36-2 with a Yanmar 3HM35F engine is zinc challenged. I found out the hard way....(long story).

Good Luck!!
Greg
 
Dec 29, 2008
805
Treworgy 65' LOA Custom Steel Pilothouse Staysail Ketch St. Croix, Virgin Islands
I too would like to know what other uses would be appropriate for this product. It probably shouldn't be used where loctite should be used! Looks like one might use it on rigging where dissimilar metals are in contact with each other, for example.

Gonna have to get me some!
 

Ross

.
Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
Probably very good on turnbuckles. And screw pin shackles
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
Also, the new shaft saver I got had to be "fitted" to my shaft as part of the trueing up process. I love having it for the protection aspect....Had a friend who did not have one that broke his bell housing and a mount after he hit an object under water.

Greg,

I did the same see this post ! Broken Bell Housing (LINK)
 
Oct 22, 2008
3,502
- Telstar 28 Buzzards Bay
Basically, you should use it anywhere you have two dis-similar metals, particularly stainless steel and aluminum, in close contact—especially if you want to be able to separate them again. Coating stainless steel or Monel pop-rivets that are used to hold things against an aluminum spar is an excellent idea. :) Also, works to prevent stainless steel on stainless steel galling IIRC. :)

I too would like to know what other uses would be appropriate for this product. It probably shouldn't be used where loctite should be used! Looks like one might use it on rigging where dissimilar metals are in contact with each other, for example.

Gonna have to get me some!
 
Jun 19, 2004
512
Catalina 387 Hull # 24 Port Charlotte, Florida
I would have one in a heart beat, have had them on past boats but they do not work with a v-drive and nobody makes one that will work with my tranny. Also it is not just as simple as sliding one in as the prop shaft should not hang out beyond the strut any more than the diameter of the shaft. Adding a Drive saver can cause shaft whip if you did not build the shaft and cut it at the right length to compensate for the flexible coupling. In essence adding a flexible coupling to a properly fitted shaft will result in an improperly fitted shaft..

So then, I guess the only alternative would be an expensive torque limiter and that also would involve having to cut to custom length the shaft.

It's too bad this happened, but like you said, it's an addiction. I can think of far worse habits to be dumping money on. At least this is a clean and wholesome one!

From looking at your other post that showed the fracture of the bell housing, it seems that this was something waiting to happen as the casting seems to have imperfections in the material composition; and really to determine if this were true would involve examination beyond the capability of the naked eye.

So a little bit of the Tef-Gel goes along way? I imagine the small syringe lasts you a long tiime?