B&S crankcase breather sealant

[Changy]

Hi to all,

I agreed to look at a mower for a client who is also a good friend. It has the B&S 650EXI engine that made a horrendous noise when pulling the cord to start it. The flywheel guard had cracked and one of the bolt retainers had snapped. The recoil was misaligned hence the noise.

I've never replaced one like this but it was straightforward until I realised I didn't have the correct sealant for it and the B&S version is like rocking horse manure. I would appreciate your recommendation on the best alternative sealant to use. It's a 10-day wait for the B&S sealant and the guy wants his mower back.

Thank you in advance

[Mick]

I would just use either Honda's Hondabond sealant or the Stihl Dirko sealant. Both of these are resistant to high temps etc and should be easily obtainable online.

Just search Hondabond or Stihl Dirko




 

[Changy]

I would just use either Honda's Hondabond sealant or the Stihl Dirko sealant. Both of these are resistant to high temps etc and should be easily obtainable online.

Just search Hondabond or Stihl Dirko

Thanks, Mick.

Is this supposed to bond the two parts? I did some research and I read that some don't fully harden. I assumed it should bond the two parts because when I removed the old guard, it held on for dear life!

When I used gasket sealant on car engines I would let it partially cure and then mate the two surfaces. When watching videos, some people leave it for a period before bolting it up whereas others just bolt it immediately.

What is your preferred method?

Thanks again




 

[Mick]

Yep, that's why I mentioned Hondabond it does bond pretty well if if you've ever tried separating a crankcase or removing a valve cover from a Honda GCV engine you'd see the cover bend before the sealant gives up. It's just a tad expensive.

I just remembered some other stuff you can get from any diy store or Screwfix Toolstation etc, it's called CT1 Adhesive sealant, this stuff is amazing and comes in various colours.  You'll end up finding many uses for it just as I did. It lasts for ages too.

[Changy]

Every day is a school day. I learned that Dirko is made by Elring. I use their gaskets whenever possible and recently rebuilt a BMW diesel engine using Elring.

Amazon are selling Elring Dirko for £5.90

[Changy]

Yep, that's why I mentioned Hondabond it does bond pretty well if if you've ever tried separating a crankcase or removing a valve cover from a Honda GCV engine you'd see the cover bend before the sealant gives up. It's just a tad expensive.

I just remembered some other stuff you can get from any diy store or Screwfix Toolstation etc, it's called CT1 Adhesive sealant, this stuff is amazing and comes in various colours.  You'll end up finding many uses for it just as I did. It lasts for ages too.

I may have some CT1 lurking in the depths of my garage. I used that to bond some parking distance brackets to a bumper and that stuff also held on as if its life depended on it!

What sort of temperature would that breather reach; I'm curious.

[Mick]

I may have some CT1 lurking in the depths of my garage. I used that to bond some parking distance brackets to a bumper and that stuff also held on as if its life depended on it!

What sort of temperature would that breather reach; I'm curious.

It get's pretty warm just as most of the crankcase does, but that CT1 should handle it ok.