Hi All

 

What is the most popular sealant for crankcases etc on a Villiers motor.

Its 40years since I last did a two stroke.

 

Thanks in advance.

I use silicone. If you can hand tightened the holding screws and then leave for 20 -30 minutes before finally tightening. If the bearings are already on the crank, just go straight to tightening with warm cases.

I use a good quality clear instant gasket and the proper paper gaskets. never had a problem with oil or fuel leaks  

ThreeBond TB1184

Hylomar Universal Blue, a non-setting, fuel, oil, and lubricant resistant joint compound.

Get the same sealant that Honda,Yamaha or the other two Jap manufacturers use. I prefer to use Yambits who will supply decent sealant its grey and does a good job. Like you its years since a I did a Villiers engine cases, just ensure that the mating faces are flat and go easy on any sealant you use. Too much and it will squish out and inside the crankcase which you don’t want to happen. Apply the thinnest of beads closer to the outer face sealing areas, leave to skin over say 4-5 mins then go for assembly. As an aside I use the Yamaha sealant on Caterpillar V-8 marine engines at service and repair intervals and also on the heat exchanger flanges, used it on Bultaco and of course Yamaha cases. Hylomar mentioned by nh014 was used by Rolls Royce and is good stuff if used correctly and might be more in keeping for your Villiers engine. Give Villiers Services a call they may recommend what they use. I’m fairly sure the crankcases are the only area where there is no gasket. You may need more than one gearbox to crankcase gasket as thats the way to correctly set the primary chain tension. Out of interest what model Villiers are you working on? 

Note if you use Hylomar it tends to separate out in the tube so try to mix it by squeezing the tube a few times, capped of course, to mix up the contents otherwise what comes out is runny liquid and no main constituent.

Edited June 18, 20206 yr by section swept
added material

 You can never go wrong with yamabond 4. Even amazon carries it.

Edited June 19, 20206 yr by lineaway

Thanks for all your replies.

Ready to push on with build now.

 

Not relevant to the Villiers, but just in case anyone is tempted to use the above mentioned Blue Hylomar elsewhere. Many years ago it seemed to be the answer to the head gasket problem on my Guzzi Monza and indeed it sealed well. Then I read about a Honda that had died because excess Hylomar had broken off and choked the oil filter. I checked and mine was heading that way so I used it up on things where this would not be an issue.

Edited June 21, 20206 yr by 2stroke4stroke

On 6/21/2020 at 10:47 AM, 2stroke4stroke said:

Not relevant to the Villiers, but just in case anyone is tempted to use the above mentioned Blue Hylomar elsewhere. Many years ago it seemed to be the answer to the head gasket problem on my Guzzi Monza and indeed it sealed well. Then I read about a Honda that had died because excess Hylomar had broken off and choked the oil filter. I checked and mine was heading that way so I used it up on things where this would not be an issue.

That happens when excess amounts are used, applied sparingly the Hylomar works well without causing oilway and filter clogging. A thin bead in the centre of the mating land will spread when compressed between both mating faces. Too thick a bead and hey presto it squeezes out both sides. Best practice is to apply a thin bead and wait 4-5 minutes before assembly.

What you say is true, done properly there is normally no problem as excess compounds tend to stay in place.  The Hylomar sets to a very rigid state and any excess breaks off sending hard bits in to circulation.  No great problem on a two-stroke as they either get chewed up in the transmission or disappear out the exhaust. Perhaps it's now packaged in a tube with a dispenser that enables a thin bead to be deployed but thirty years ago it was like dealing with toothpaste?

9 hours ago, 2stroke4stroke said:

What you say is true, done properly there is normally no problem as excess compounds tend to stay in place.  The Hylomar sets to a very rigid state and any excess breaks off sending hard bits in to circulation.  No great problem on a two-stroke as they either get chewed up in the transmission or disappear out the exhaust. Perhaps it's now packaged in a tube with a dispenser that enables a thin bead to be deployed but thirty years ago it was like dealing with toothpaste?

Came in a tube then, it was all we were allowed to use, well that and ‘ hold me tight’ or Hermetite red semi hard setting and green hard setting. But we all knew Hylomar was best!