Dirko sealant for a clamshell crankcase? (MS250)

[Chain-sore]

I need to take an MS250 apart and was wondering what sealant to use on the crankcase.

 

I keep reading about Dirko but which colour? I can get grey at my local Euro Car Parts tomorrow so it would be ideal if that'll do it.

 

Is there something better for the job? I rather not have to take it apart again too soon.

 

Oh and would it be silly not to replace the crank seals as it's in pieces? The saws running fine at the moment.

 

Cheers

[Macpherson]

Hi, Not used Dirko but a quick google say's it may be silicone based.... silicone sealer usually gets perished by petrol although it's fine with engine oil. .......

 

Everyone has their own preference but mine is blue Hylomar.

 

Hylomar® Universal Blue 100gm | Glue Online | Adhesive Solutions

WWW.GLUEONLINE.CO.UK

---

Hylomar® Universal Blue is a non-setting and non-hardening, polyester urethane based sealant that is resistant to a wide...

 

Yeah, I'd do the seals and probably the bearings as well for all they cost....before you strip it see if you can feel any up and down movement in the crank, should be zero

[Paddy1000111]

I use Hylomar blue. It's a "non-setting" sealant so it never hardens or looses it's seal. You put it on both parts and leave it until the solvent evaporates and it becomes like extremely tacky rubber. You can also put a very thin layer on paper seals. I've never had a crankcase leak when using it, I found out about if from the Kart racing guys.

[Cut4fun]

Same stuff stihl uses OEM and sells. Red

 

 

Edited November 19, 2020 by Cut4fun

[Chain-sore]

This of kind of why I asked because I'd read that some sort of Dirko was used by Stihl but yeah, Elring's own site says it's not suitable for petrol.

 

 

I'd almost forgotten about Hylomar. I think I have a tube of it somewhere, probably from the 90's..

 

Hmm.

[Paddy1000111]

Hylomar universal blue is the only thing I found that was resistant to pretty much everything on earth. I'm reluctant to use setting sealants on stuff as I always find that it doesn't bond in one place or you can't get it apart in the future or it sets as you're assembling. To be fair to Hylomar it's worked perfectly, designed for metal to metal, rated from -50 to +250 and seals like nothing I've ever seen but you can still take things apart if you need to! 

[Macpherson]

8 hours ago, Chain-sore said:

I think I have a tube of it somewhere, probably from the 90's.

Might not be up to much if it's been opened, I use the stuff a lot and once air gets in the tube it gets much less fluid?

Developed by Rolls Royce and for anyone interested cellulose thinners is a handy solvent for it 

Edited November 19, 2020 by Macpherson

[peatff]

Threebond does it, or Hermetite red

[spudulike]

Hylomar was the approved liquid gasket for Honda horizontally split fours in my day. I use Carplan Red Instant Gasket as it has a decent temp range but many products will do the job in the same way.

[Chain-sore]

Well I bought a new tube of Hylomar and used that. White spirit got the old red sealant off easily which was handy as someone had been a bit generous with it. There was a fair bit inside the casing.

 

It's a low hours saw so I convinced myself the bearings and seals were serviceable. It's back together now and runs a beauty.

 

Thanks chaps.