Sealing compound for joining the crankcase halfs

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concours said:
boz said:
Jim you probability can't find the Three Bond etc. in local shops because of the solvents. I remember about 10 years ago the original Yamabond disappeared because the EPA banned it.

https://www.rockymountainatvmc.com/p/30 ... sket-Maker

Yeah, but they have changed the formula [or at least the part number] and it's still available. The kids at the local Yamkawzuki shop didn't know what it was and the local Harley shop was out of it. Amazon got it to me fast. Jim
 
Thanks for the clue about using non-waxed dental floss. My crankcases always leak at the joint between the halves. This has given me another reason to strip the 850 motor and rebuild it with the combat cam.
 
Nater_Potater said:
hobot said:
...might consider organic fiber thread laid in the seams as traditional on problematic aircoolled aricraft...
'Was taught in A&P school to lay #40 silk thread along seam after applying sealant to act as a "crush washer". It works well!

This is the aircraft engine trick that Hobot was talking about. It is a very good solution for engine case halves.
 
Just do NOT use the common synthetic threads as they melt and contract to leave voids in sealants so only real silk cotton, wool or hemp thread which is a bit pricy for the amount needed. Its tedious tricky to get thread to lay down and stay put to add sealant and clamp down. If an oil tight Commando is run in damp conditions or stored to open air the non SS parts of fasteners with rust to notice in about a season and have not found spray on that stays on engine fasteners beyond that. Prior I put light coat of blue snot on via Q-tip to press thread into and add layer over that but next time will coat tread in goop, let get tacky to stay down as its laid down and not disturb it adding the full dose. My favorite one goop seals everything head to tranny and home plumging projects costs more than $50 for 75 ml nowadays. I found some ancient mercerized cotton thread in my 95 yr old aunt Alice sewing kit on wooden spools to boot. I see cotton thread offered in http://www.deutscheoptik.com/ catalog for $9 a spool plus shipping and worth some window shopping or hard copy catalog of vintage and new craftsmanship items galore.

http://www.valco-hylomarproducts.com/hi ... 20blue.pdf
http://www.hylomarsealant.com/_resource ... ducts.html
https://www.youtube.com/watch?v=yXiVZIBoHL0
 
We used to have the thread in the shop with a Continental Motors P/N on the spool. I'm pretty sure it was silk.
 
My next trip to Bangkok I will pick up a nice roll of natural uncoloured silk thread. PM me if you need any free , plus letter postage. This winter. :wink:
 
Wellseal. It works fine an if it gets into oil ways the oil washes it away. If your joint faces are good then that is all you need.
 
JimNH said:
This is a list of TCM approved sealants, oils, etc. Near the end is an illustration of how to apply sealant and silk thread on crankcase halves.

http://www.tcmlink.com/pdf2/SIL99-2C.pdf

Good info .... thanks Jim! I will print this out and keep it handy.

Once more, the wealth of knowledge possessed by Forum members is demonstrated, to the benefit of all, and access to such knowledge is well worth the price of VIP membership.

Slick
 
I used the Hylomar, but I'm sure I must not have put it on right as I have leaks at the bottom of the engine around the front/bottom stud, mostly when it wet sumps or I ride it. I found it difficult to work with because of it's acetone solvent (dries quickly) and ended up applying it right out of the end of the tube onto the flange, but I never did feel confident that I got enough on and in the right places. It seemed smeary and hard to make any consistent buildup. Are there any instructions about using it? Or I may break it down one of these days and try the Permatex. This kind of thing happens to me, I'm glad everyone else has luck. It leaked horribly as factory build, but not sure everything else wasn't leaking too. I did whack out the chain oiler early on.

I used to think of it as a mobile oil puddle, but it's lots better now, at least manageable. Of course when I went from SAE50 to V-Twin Syn, it started leaking more.
 
DogT said:
I used the Hylomar, but I'm sure I must not have put it on right as I have leaks at the bottom of the engine around the front/bottom stud, mostly when it wet sumps or I ride it. I found it difficult to work with because of it's acetone solvent (dries quickly) and ended up applying it right out of the end of the tube onto the flange, but I never did feel confident that I got enough on and in the right places. It seemed smeary and hard to make any consistent buildup. Are there any instructions about using it? Or I may break it down one of these days and try the Permatex. This kind of thing happens to me, I'm glad everyone else has luck. It leaked horribly as factory build, but not sure everything else wasn't leaking too. I did whack out the chain oiler early on.

I used to think of it as a mobile oil puddle, but it's lots better now, at least manageable. Of course when I went from SAE50 to V-Twin Syn, it started leaking more.

That's why I like Wellseal. I decant it into a small glass jar and use a small, modellers, paint brush to apply it. It is far easier to apply a uniform thickness and ensure its covering the right places that way.
 
wellseals the one, Mick Hemmings has used it for years on crankcases and cylinder head gaskets. He`s never had a leaky head gasket, and if you get it on the case sides it wipes clean off with petrol.
 
texasSlick said:
JimNH said:
This is a list of TCM approved sealants, oils, etc. Near the end is an illustration of how to apply sealant and silk thread on crankcase halves.

http://www.tcmlink.com/pdf2/SIL99-2C.pdf

Good info .... thanks Jim! I will print this out and keep it handy.

Once more, the wealth of knowledge possessed by Forum members is demonstrated, to the benefit of all, and access to such knowledge is well worth the price of VIP membership.

Slick
Thanks JimNH. I reinforce Slick's sentiment. Excellent resource and well worth paying the price for membership!
The first few pages re products and applications are brilliant - I'd not heard of Dow Corning "MOLYKOTE® G-N METAL ASSEMBLY PASTE" for cam assembly and bedding-in.
I especially like that the document is current i.e. 21st century revised in 2014.
Ta.
 
Interesting. I've found several people in the industry who have used both Wellseal and Hylomar (which I have used for years, and like) and prefer Wellseal. I'd like to give it a try, but a quick google search only shows me one source of Wellseal in the US, at Pegasus racing, and they charge an extra $40 fee because it can't be shipped by the Post Office or UPS ground, but has to go by UPS air. They have the same requirement for shipping Hylomar blue and Hylomar Solvent Free Gasket Maker. Kind of pricey, unless you're buying it by the case.

Anyone know of another source here in the US?

Ken
 
It is interesting that my Norton Owner's Manual (the one that came with the new machine) recommends sealing the cases with Wellseal ..... that was written in 1962!

I was never able to find it in the US. When I split my cases back in the early '70s to stop a leak, damfino what I used to seal the cases, but whatever it was, not a drop from the case seams since. If I split them again, I'll be looking for Wellseal AND silk thread!

Slick
 
Hi Ken,

Hope this link works. It is expensive to ship by air because it is hazardous (flammability most likely) but $11.25 by UPS ground. Six tubes are $13.02 ground shipping. Maybe they won't ship ground to CA I think you are there? If not PM me, you can pay me to buy it for you and I will send it to you for, as they say, "no extra charge." I put in the Beverley Hills zip and the ground cost was same.

https://www.pegasusautoracing.com/reviewcart.asp


ebay, would take a bit but about the same price?
http://www.ebay.com/itm/Stag-Wellseal-J ... 565718ee69

Update: I got interested it is not flammable or reactive; the solvent is a chlorinated hydrocarbon and is a health hazard. UPS rates it as a "poison" and it attacks the central nervous system. Be a PIA to ship without a trained guy to pack it and do all the necessary paperwork in the US. You would not want to breathe this long term.


lcrken said:
Interesting. I've found several people in the industry who have used both Wellseal and Hylomar (which I have used for years, and like) and prefer Wellseal. I'd like to give it a try, but a quick google search only shows me one source of Wellseal in the US, at Pegasus racing, and they charge an extra $40 fee because it can't be shipped by the Post Office or UPS ground, but has to go by UPS air. They have the same requirement for shipping Hylomar blue and Hylomar Solvent Free Gasket Maker. Kind of pricey, unless you're buying it by the case.

Anyone know of another source here in the US?

Ken
 
Enjoyable read hearing the wide variety of sometimes differing experiences with a wide variety of sealants.

Ole rwalker28 beat me to the punch on pointing out the toxicology concerns of several of these sealants, and his points are well taken. For example Wellseal contains perchloroethylene and Hylomar contains dichloromethane - both chlorinated solvents that present health concerns. It is the presence of these chlorinated solvents that render the compositions non-flammable.

If you read the MSDS sheets on these you'd likely never touch either of them. However if you read the MSDS sheet on lacquer thinner, paint remover, carb cleaner, and many other common household products, you'd never touch them either.

My intent is clearly not to scare anyone - more the opposite - I don't want people to be scared away from common things that can be used safely. I just find it humorous that over on the thread "Needing Air", some people were all excited about the hazards of a can of carb cleaner. Well if you were concerned about using carb cleaner, you'd really be concerned about using the subject sealants. Maybe the thread title "Needing Air" was foretelling, since we find ourselves Needing plenty of fresh Air to use these products.

Like always, a little common sense goes a long way toward minimizing health hazards, e.g.,
• don’t huff the stuff,
• don't get it on your skin (wear protective rubber gloves if you'll be contacting the sealant)
• don't use it in a confined area with no air exchange - the better the ventilation the better off you'll be
• don’t use it for extended periods of time, or use large quantities of sealant unless ventilation is excellent

The above suggestions are just that, suggestions. The most important thing you can do is to perform your own search to assess risks and determine how to safely handle materials containing these solvents if you choose to use them. They can be dangerous - as a prime example look what they've done to me. :oops:

Getting back to the subject of sealants, I'm in DogT's camp on the Hylomar as I don't care for it and have had bad experiences using it. Might have to see if I can get a personal audience with LCRKEN to figure out why my experiences with Hylomar are less than stellar.
 
Well, rwalker28 piqued my interest, so I've ordered a tube each of Wellseal and Hylomar Blue (I'm almost out of it anyhow) from Pegasus, and the receipt shows the cost of shipping UPS ground, and no mention of the $40 HAO hazardous material fee. However, their web site and catalog still say both materials are HAO and will require the $40 fee, and must be shipped UPS air. AND, the receipt that shows just the $13 UPS ground fee calls the total cost an "Estimated" total. I fully expect to hear from them, with the additional $40 charge added, at which point I would hopefully be able to cancel my order. The last time I bought a tube of Hylomar Blue, I had to have the local NAPA store order it, but at least there were no extra fees for shipping, HAO, or anything else. I'll report on whether the order goes through.

Ken
 
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