carb rebuilding

[chris mig]

so my rebuild kit came with this thick base gasket with 3 holes one which goes to nothing so 2 of them go to manifold studs but i have four studs can i just drill out the other two holes? Why would they even do this? BTW IT IS A MERC 485 with a rochester 2 barrel carb

 

[jimmbo]

Rebuild kits often include gaskets that are not needed on a rebuild. Makes for a smaller inventory. However, do you have the correct kit? There is a chance the gasket was manufactured incorrectly

 

[chris mig]

jimmbo thanks for your response it is the correct kit and looking at pictures on sites with the gaskets layed out they seem to all be that way. I have researched this thicker gasket and seems to be the recommended way to go for keeping the carb cool and better for idle mixture adjusting just dont get that any carb would ever bolt down on two of four corners

 

[NHGuy]

They always give you gaskets for multiple apps. Use those that duplicate what came out, or what the rebuild guide shows.
Take lots of pics before & during disassembly. You will be glad you did.

 

[chris mig]

thanks NHGuy i am all good with the rebuild it is just the base gasket that has me stumped as i have been reading on other threads and such about the benifits to the thick gasket between manifold and carb for keeping the carb cool and better idle mix adjustment

 

[NHGuy]

If you decide to drill them yourself the best way to be neat about it is to use wood to sandwich the gaskets. That way they won't tear.

 

[chris mig]

this gasket is like 1/4 to 3/8 in thick it shouldn't tear but i will use a old base plate and screw it down on wood then drill out the other two holes

 

[jimmbo]

With a thicker gasket there may be more squishing of the gasket, therefore only two of the original 4 bolts may be enough

 

[chris mig]

With a thicker gasket there may be more squishing of the gasket, therefore only two of the original 4 bolts may be enough

so maybe drill out the two holes and dont bolt them down vs removing them? this way if it doesnt work i can go back to the thinner gasket. And wont loose the studs. After looking closer at the gasket it has two sleeves around the holes to limit squishing. I think I will be tring this method. On second thought I will try to remove the studs to give more surface area to the gasket.