Work time to apply Motoseal (Threebond, Hondabond, Yamabond) to crankcase joints

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After reading through the threads on various crankcase sealers to use on Commandos, I'm leaning towards Motoseal. This product is virtually the same as Threebond 1184, Hondabond, and Yamabond. All are solvent-based products that produce a synthetic rubber seal. The manufacturer's instructions say to apply the product, smooth it out with a brush, and wait about a minute before assembling. I interpret this as a minimum time to wait before assembly, but can anyone who has used these products suggest how long it takes to apply this material to a Norton crankcase as well as a maximum working time I have before I must assemble it?
 
Let me ask.... as I have yet to need to pull apart my engine and reassemble!
Is Permatex Aviation form a gasket 3 a candidate to use as some have recommended it?
Dennis
 
By the time you get to the end of the application, the place you started will be well past any minimum time! Takes a while to apply all round.

And if you take as much time as I do to put the cases together you will realise you have quite a lot of work time, meaning, I have never had to clean it off and start again!

Just get it even, and don't put on too much.

Why use something that may be 'virtually the same' as Threebond 1184, when Threebond 1184 is readily available?
 
Let me ask.... as I have yet to need to pull apart my engine and reassemble!
Is Permatex Aviation form a gasket 3 a candidate to use as some have recommended it?
Dennis
It's the only sealer I've ever used for Norton, Triumph, and BSA crankcases. I may be the only one here still using it.
 
I sent an email to Permatex tech support, they just got back to me... Motoseal has a 10-minute working time. I suspect guys who have done this before can do it easily in under 10 mins, concours is a hero at it, but me... I may need to practice.

Greg, I asked Permatex about Aviation and their Anaerobic sealer as well. They recommended Motoseal or their Anaerobic Sealer for this application. They said Aviation #3 was best when you are "augmenting" a gasket. I know it has worked for you, and application is far easier, so I may end up do that in the end. Applying anaerobic sealers is as easy as Aviation #3, just not sure how well it holds up, believe I read it can leak over time, so perhaps best for race motors that come apart often. Can anyone weigh in on the durability/longevity of Anaerobic Sealers, permatex or Loctite 515 / 518?
 
Greg, I asked Permatex about Aviation and their Anaerobic sealer as well. They recommended Motoseal or their Anaerobic Sealer for this application. They said Aviation #3 was best when you are "augmenting" a gasket. I know it has worked for you, and application is far easier, so I may end up do that in the end. Applying anaerobic sealers is as easy as Aviation #3, just not sure how well it holds up over longer periods of time, believe I read it can leak over time, so perhaps best for race motors that come apart often. Can anyone weigh in on the durability/longevity of Anaerobic Sealers, permatex or Loctite 515 / 518?
Need to suggest to whoever told you that that they should read their own sales documentation and TDS!

I have one engine I built in 1971 that has never leaked (Triumph T100C rebuilt as T100R)

From the Permatex Web site:

Product Description​

Permatex’s Aviation Form-A-Gasket No. 3 Sealant Liquid is a slow-drying, non-hardening brush top sealant approved for use in aviation as well as automotive applications. It’s resistant to gasoline, oil and grease.

-and-

"Permatex Aviation Form-A-Gasket No. 3 Sealant Liquid 16 oz (80017) is a high-performance sealant designed for use on gaskets, machined surfaces, and screw thread connections in airplane and automobile engines.

This sealant is pressure resistant and leakproof, making it ideal for a wide range of applications. Permatex Aviation Form-A-Gasket No. 3 ensures that parts disassemble easily even after extended service, providing a durable and dependable solution for your sealing needs."

From the TDS:

Work time to apply Motoseal (Threebond, Hondabond, Yamabond) to crankcase joints
 
I used to use 515 for many years but I put my 850 barrels on without a gasket as per the manual with 518 and it weeps so will not be using it again. like Greg I have had good success with Permatex Aviation 3.
 
Need to suggest to whoever told you that that they should read their own sales documentation and TDS!
Yeah, I saw that too, sure seems to cover things. They were responding to my questions on all three products, so I suspect they were simply rank ordering the choices.
 
After reading through the threads on various crankcase sealers to use on Commandos, I'm leaning towards Motoseal. This product is virtually the same as Threebond 1184, Hondabond, and Yamabond. All are solvent-based products that produce a synthetic rubber seal. The manufacturer's instructions say to apply the product, smooth it out with a brush, and wait about a minute before assembling. I interpret this as a minimum time to wait before assembly, but can anyone who has used these products suggest how long it takes to apply this material to a Norton crankcase as well as a maximum working time I have before I must assemble it?
Original sealant on later models was a Loctite product with high shear resistance, also used on Porsche cases to reduce “shuffling”, fretting movement between case halves. Indication of shuffling is a fine grey paste deposit. For normal street use Yamaha Bond or similar products are acceptable.
 
With Yamabond it depends on the temp of your workspace. On a hot summer day I have to work quickly. On a winter day, much longer. To spread it around I use a wire tie as a spatula and it works quite well. I've used Yamabond for years with no problem.
 
Thanks for the feedback. For those who use one of the bonds, do you spread the material right up to the inside edge of the mating surface or back away a bit to prevent seepage into the crankcase once it's assembled? What do you do around the oil drain hole... other than the obvious, don't block it?
 
I've used Yamabond, and it works well. I like Loctite 574, which is what Porsche used on their cases for the 911 engines.
 
Happy New Year, Fellow Nortoneers,
I am going to use Threebond 1194 this time around on my rebuild 74 850. I used Wellseal on the last time I rebuilt this engine and it was OK.
I use Wellseal on head gaskets and it works there too.
Cheers,
Tom
 
Threebond for me. Put a rubber glove on and put the threebond on your finger and smear it on covering the entire face. All you need is an ultra thin smear not a bead. Wipe off any offset. If you are using it for other gaskets just put it on one side on things like the gearbox cover, rocker covers or timing cover that you might have to remove. Put some grease on the other side. It is a bear to get them seperated if bond is used on both sides.
 
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