Why threebond instead of 574 on case?

[3literpwr]

As I approach my build, i'm wondering what is the reasoning for using Threebond on the case perimeter? Stays flexible? Less prone to leaks?

Thanks

[cgarr]

I don't think it's any better than 574 if the 574 is done right which requires nice machined surfaces like in the factory threebond may be more forgiving on less than perfect surfaces.

[Henry Schmidt]

According to the product specifications, ThreeBond seals a larger gap with all things being equal.

In race engine applications, ThreeBond is easier to remove making freshen ups considerably easier.

Under most circumstances, 574 will perform adequately, but our experience has pointed us toward a multi glue sealing system that seems less prone to failure.

[JFairman]

I thank Henry for teaching us about good alternatives to loctite 574 which is not fun to remove in the future if you ever have to do that.
If you have a Honda or Yamaha motorcycle dealer near you go to the parts dept and you can buy rebranded threebond 1184. Honda calls it Hondabond 4 and Yamaha calls it Yamabond.

I went to the local honda dealer and got the 3.5oz tube of Hondabond 4 for less than $7. I'll be using it on the cylinder head to cam tower sealing surface when I put mine together probably next week.
I like to use blue hylomar on the chain case gaskets and it works really well. It should work well anywhere the green Curil T is used. It never dries and wipes off any time in the future with laquer thinner on a rag. I think the hondabond 4 would work well there too.

Here's the hondabond4 from an internet seller.
Dirt Bike Pro Honda Hondabond 4 - 3.5oz | MotoSport

[3literpwr]

Thanks for the inout guys...

[HawgRyder]

If you have serious leakage in the case joint...you can try the old aircraft fix.
We used to put a single silk thread along the sealing flange so that it sticks in the 574 or whatever you use.
With some of the old aircraft engines...the flange was pretty bad looking...and trying to seal them with just goo was almost impossible.
Bob

[cgarr]

Originally Posted by HawgRyder

If you have serious leakage in the case joint...you can try the old aircraft fix.

We used to put a single silk thread along the sealing flange so that it sticks in the 574 or whatever you use.

With some of the old aircraft engines...the flange was pretty bad looking...and trying to seal them with just goo was almost impossible.

Bob

LOL tell me about it, here is a C-85 case that they want you to try and seal! No. 50 silk thread, hell I'm thinking rope!

[Henry Schmidt]

I think that "thread" trick is a throwback to the Rolls days.
A long time ago, before I knew better I built an engine for a 1925 Rolls Phantom. On my list of parts was a pan gasket. I waited weeks for the parts and then months.
It seemed even when I was young, pre-war parts for RR were like rocking horse shyt, very hard to find. When I final got all the parts, I was disappointed to find no pan gasket. I made a quick call to the supplier in England only to find that the little envelope with the small coil of wax coated string was in deed the pan gasket.
The next day, I borrowed the use of a friends mill and cut an o-ring groove around the entire sealing surface. Problem solved.

[RedCoupe]

As Hawg Ryder said, the silk thread was also an old aircraft trick. When I was in high school, I helped my father (who had his A&P) rebuild a Continental E225 flat six engine to go in a 1948 Beech Bonanza. The two crankcase halves were sealed by painting Permatex aviation sealant on one half and laying a silk thread in the sticky sealant. Years later it still didn't leak.