Intake manifold problems

[murfman55]

On the bottom side of the intake manifold there are some circles that appear to be plugs of some sort. I have one that rusted through, are these replaceable? If so where would I get them? Thanks!

[gillis51]

They are 1 1/8" welch plugs. Check useful parts list for the part no. You can get them at NAPA

[Mark Pietz]

Hardest part of replacing them is getting the manifold off and then back on. Simply pry out the offenders and tap in the new ones. If one is rusted through, the rest are sure to follow. Do them all and then forget about 'em.

[Eric VanBuren]

While you've got it off it's a good time to do the valley pan gasket and PCV grommet.

[robgimmel]

If you can find brass plugs, you will never have to worry about them again.

[Paul "Misterfixit" Schulz]

Originally Posted by robgimmel

If you can find brass plugs, you will never have to worry about them again.

Don't be too sure about that as some of those plugs are in exhaust gas recirculation ports!

[murfman55]

Thanks guys, new gaskets and seals all around is planned so a few more plugs won't hurt! Thanks again.

[murfman55]

This maybe sort of a stupid question but I looked up the part from the useful parts list at napa and what it shows looks flat across it and what is on the bottom of the intake manifold is more convex in shape. Does it really matter as long as it seals the hole?

[gillis51]

Check my post under useful parts and use the model no I posted. It is current and corect for a 79 345.

[murfman55]

I guess I was expecting something more like a freeze plug.