BrianG

I am reassembling an Italian motorcycle transmission that does not have gaskets between the machined case parts, and it oozes gear oil. Gear oil stinks and it makes a fugly mess.

I want to reassemble the case parts with a good sealer and have heard that Threebond makes good products but I am unable to decide between two of the products:

Threebond 1104 or 1211


Anybody have any experience with this stuff? An opinion about which to use?

Jim M.

I don't have any comments on which sealer to use, but years ago recip. aircraft engines were sealed with thread on aluminum to aluminum parts. I did it to a Triumph motorcycle transmission and it never leaked a drop after that. I used the thinnist smear of Permatex just to hold on the thread to the case.

Jim Mayzurk
93 GTS 5-spd

AO

Permatex makes some stuff called, "The Rigth Stuff" It's like a rubber RTV. Holds up under heat, pressure, oil, etc. and remains elastic. It can be hard to find sometimes, but I've been having luck finding it at Autozone. It comes in a Cheeze-whiz type of can and costs about $12/can. It sets up pretty quickly, but for your application I'd proabbly wait a good 24 hours before running.

One word of warning, this stuff is like antisieze in that if you get it on your fingers 1. it doesn't wipe off easily 2. you'll find it everywhere. Messy stuff if you're not careful. I learned from Tony H to mask of the areas around it, apply the bead, assemble the parts, smooth off any excess, then remove the tape. Makes for a clean install. Hope this helps.

Ed Hughes

Go to the 911 engine rebuild section on Pelican. There is a lot of discussion there on case sealing, as the 911 case is metal-metal also. Some good anaerobics talked about, definitely different opinions.

Bus

I know, sacriledge for an american motorcycle... but "Yamabond" is the best stuff I've used.

I use the permatex products on a lot of other automotive stuff, and as a superthin smear on gaskets to make them come apart better in the future. My 928 oil pan is sealed with black permatex... with the right technique, it's wonderful. Learned the technique at a Dodge dealer in the early nineties, and when I worked in Cummins for tech support, we had a tube of thier sealer on every workorder....

heinrich

Agreed, X2 on Yama/Hondabond.

BrianG

Unfortunately the old Yamabond #3 is no longer available. I have come to discover that Yamabond #3 and Hondabond is made by Threebond and is actually brand-packaged 1104.

The thread trick is apparently a common sealing strategy used in the aviation industry for sealing case halves. If it's good enough for the Comanche, it's good enough for the Guzzi!

I guess I'll use the Threebond 1104 with thread.

mark kibort

locktite 518 or yamabond. we did scots engine in 518 and it works great. very thin application with a rubber glove finger on one side (i did two sides and it was a little too thick)
mk

the flyin' scotsman

Brian..............if you cannot buy Yamabond anymore what are the m/cycle shops using to seal their engine crankcases? I would ask at the local parts dept of the Yamaha/ Honda/ Suzuki dealer.

I may have some Yamabond in my tool box; want it?

Bill Ball

I've used 1104, which is non-hardening, interchangeably with Yama/Hondabond. On the 928 I use it for the water pump and tensioner gasket, but not much else. The 1200 series is silicone-based, cures solid (but flexible) and seems to have higher heat tolerance than the 1100 series. Funny, I don't see 1104 at the Threebond website, although I can buy it online at various motorcycle part suppliers.
http://www.threebond.co.jp/en/produc.../1100list.html

However, it looks like this Guzzi source recommends 1104 over "silicone-based goo".
http://www.mgcycle.com/chemicals.html

Garth S

I've had excellent performance from Loctite 515, an anerobic sealant for metal to metal joints.

BrianG

There are newer Yamabond products (with higher numbers), but I am unfamiliar with them and their designators. Since it seems that these products are just brand-labled Threebond products I thought I see what the 928 brotherhood uses and source it direct from Threebond.

Thanks, Malcolm. I'll just decide on which current product is best and go with that.

mark kibort

this is the stuff most engine porsche guys use for sealing metal to metal surfaces without gaskets. I dont think you want to use the silicon based sealant

mk

atb

Mark,

Why did you loctite the bearing saddles?

the flyin' scotsman

No worries Brian.

I know these folks http://revoluzione.com/index.html quite well; let me know if I can help.