Stripping MS 171

[Macpherson]

Red stuff is Dirko, highly rated by all accounts but expensive. I use high temp silicone sealant from Aldi I guess i need to test it for 10 years before i can say its any good.

bmp01

 

Hi, just to say that although silicon sealer is great stuff unless there's been a new type developed that I'm unaware of it's dissolved by petrol.

 

For many years while working on motorcycles I removed silicone sealers from engine parts the easy way by leaving it to perish by placing the components in a bath of petrol, it doesn't take long.

 

I also often encountered endless fuel system problems where silicone sealants had been used on carbs and manifold joints etc...... of course most of these machines were 4 stroke, I wouldn't use silicone on any part of a 2 stroke that comes into contact with petrol.

 

Personally I use Hylomar when assembling engines, for which the solvent is cellulose thinners, I haven't used Dirko so I can't comment but I did notice that it's silicone based and recommended for motorcycles ..... nearly all of which are now 4 stroke..... , perhaps you should try seeing what a soaking in petrol does to it.

 

Just my take on the subject of silicone sealers, there are many different options out there... cheers.

 

https://www.cromwell.co.uk/shop/adhesives-and-sealants/gaskets/hylomar-universal-blue-medium-40gm/p/HYL7032500K?utm_campaign=pla-Adhesives+%26+Sealants+-+&utm_source=google&utm_medium=shopping-pla&utm_keyword=HYL7032500K&istCompanyId=6aa6787b-063e-4414-802d-129f235df603&istItemId=aq

[bmp01]

Hi, just to say that although silicon sealer is great stuff unless there's been a new type developed that I'm unaware of it's dissolved by petrol.

 

For many years while working on motorcycles I removed silicone sealers from engine parts the easy way by leaving it to perish by placing the components in a bath of petrol, it doesn't take long.

 

I also often encountered endless fuel system problems where silicone sealants had been used on carbs and manifold joints etc...... of course most of these machines were 4 stroke, I wouldn't use silicone on any part of a 2 stroke that comes into contact with petrol.

 

Personally I use Hylomar when assembling engines, for which the solvent is cellulose thinners, I haven't used Dirko so I can't comment but I did notice that it's silicone based and recommended for motorcycles ..... nearly all of which are now 4 stroke..... , perhaps you should try seeing what a soaking in petrol does to it.

 

Just my take on the subject of silicone sealers, there are many different options out there... cheers.

 

https://www.cromwell.co.uk/shop/adhesives-and-sealants/gaskets/hylomar-universal-blue-medium-40gm/p/HYL7032500K?utm_campaign=pla-Adhesives+%26+Sealants+-+&utm_source=google&utm_medium=shopping-pla&utm_keyword=HYL7032500K&istCompanyId=6aa6787b-063e-4414-802d-129f235df603&istItemId=aq

 

Nicely put, point taken, i was in two minds about using it, seems ok so far ... 3-4 years.

 

I used a bit of silcone hose as fuel line once. It increased its size 2 fold and lost most of its mechanical strength ie tore very easily. So yes, not very clever to use silicone sealant on the engine despite the tube of goo saying it is fuel resistant.

 

Dirko is spec'd in the Stihl parts lists. If it is also silicone based that's a worry....

 

Do you know, i think i still have a tube of Hylomar - I'll go see if i can find it and if its stil usable, must be 25 years old Good tip about the cellulose thinners, didn't know that.

 

Thanks for info.

 

bmp01

[Macpherson]

Yeah sorry, as I said I've not used Dirko, But if it's recommended it must be fine........ ordinary general purpose silicone sealant however isn't good with petrol......and you might like the Hylomar if you get a new tube