Do I need head gasket dressing??

[Emerald14]

Hey fellas?<br /><br />1968 18hp Evinrude 18803M<br /><br />Had to remove the head to repair stripped sparkplug threads. Got new head gasket, thermostat, thermostat gasket. The new head gasket says not to use sealant. Should I put any kind of dressing on the head gasket or thermostat gasket?? Or just keep it dry. I thought a very light coat of spray on copper dressing would fill any small voids.<br /><br />Also was planning on using an "anti-seize" compound on the head bolts. Would that be adviseable or not??<br /><br /><br />Thanks for the help<br />JR

 

[Paul Moir]

Re: Do I need head gasket dressing??

Do not use any copper based products. On contact with sea-water they'll eat the aluminium. Non silicone and copper based selants are fine to use though.<br />Anti-sieze greatly modifies the K factor when tightening the head bolts - the spec is for dry threads. You could coat the shanks & threads with gasket compound though and they'll be much easier to remove next time.<br /><br />A lot of knowlegable techs here use a little OMC gasket dressing on their head gaskets, even though they've got sealant embedded in them. I never do and have never had a problem, but I haven't installed nearly as many as them. If the thermostat gasket appears shiny, it's filled with sealant too. If the gasket surfaces were less than perfect, I would probably use sealant on them anyway.<br /><br />Don't forget to retorque the head after a heat/cool cycle and then again after a few.