clintC
Junior Member
- Joined
- Jun 4, 2023
- Posts
- 23
- Reaction score
- 23
- Location
- Louisville, Ky
- First Name
- Clint
- Truck Year
- 81
- Truck Model
- C3500
- Engine Size
- 350
exhaust manifold "air" ports sealant
- Thread starter clintC
- Start date
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
- Joined
- Oct 30, 2019
- Posts
- 3,125
- Reaction score
- 7,254
- Location
- Downingtown, PA
- First Name
- Wayne
- Truck Year
- 1974
- Truck Model
- Jimmy
- Engine Size
- 350
Pipe plugs do not match. What you want are inverted seat plugs.
Coat the threads with some anti-seize thread paste. The inverted seat will seal the plug. They are sold by tube size, so 1/4" tube are 7/16" threads
You must be registered for see images attach
Coat the threads with some anti-seize thread paste. The inverted seat will seal the plug. They are sold by tube size, so 1/4" tube are 7/16" threads
clintC
Junior Member
- Joined
- Jun 4, 2023
- Posts
- 23
- Reaction score
- 23
- Location
- Louisville, Ky
- First Name
- Clint
- Truck Year
- 81
- Truck Model
- C3500
- Engine Size
- 350
are you saying the plugs that came with the manifold are a bad choice???? checking to see if Nappa has what you suggested
- Joined
- Oct 30, 2019
- Posts
- 3,125
- Reaction score
- 7,254
- Location
- Downingtown, PA
- First Name
- Wayne
- Truck Year
- 1974
- Truck Model
- Jimmy
- Engine Size
- 350
Are those plugs, pipe thread? Do they have the inverted seat like the picture I posted?
- Joined
- Oct 30, 2019
- Posts
- 3,125
- Reaction score
- 7,254
- Location
- Downingtown, PA
- First Name
- Wayne
- Truck Year
- 1974
- Truck Model
- Jimmy
- Engine Size
- 350
Napa will have the correct plugs. Yes the people that design manifolds are engineers. The people that package the parts, not so much.
clintC
Junior Member
- Joined
- Jun 4, 2023
- Posts
- 23
- Reaction score
- 23
- Location
- Louisville, Ky
- First Name
- Clint
- Truck Year
- 81
- Truck Model
- C3500
- Engine Size
- 350
the plugs are solid w/ a flat bottom....nappa "search" didn't show anything, so I'm gonna call
- Joined
- Oct 30, 2019
- Posts
- 3,125
- Reaction score
- 7,254
- Location
- Downingtown, PA
- First Name
- Wayne
- Truck Year
- 1974
- Truck Model
- Jimmy
- Engine Size
- 350
clintC
Junior Member
- Joined
- Jun 4, 2023
- Posts
- 23
- Reaction score
- 23
- Location
- Louisville, Ky
- First Name
- Clint
- Truck Year
- 81
- Truck Model
- C3500
- Engine Size
- 350
thanx for all the info
they'll have 'em on tues
they'll have 'em on tues
75gmck25
Full Access Member
- Joined
- Oct 13, 2016
- Posts
- 2,261
- Reaction score
- 2,202
- Location
- Northern Virginia
- First Name
- Bruce
- Truck Year
- 1975
- Truck Model
- K25 Camper Special TH350 NP203
- Engine Size
- 5.7
Many years ago I just cut each pipe and removed the fitting. Then I fit a steel ball bearing into each fitting and screwed it back in place. It was still fine when I sold the car.
KnuckleBuster
Full Access Member
- Joined
- Jun 15, 2023
- Posts
- 61
- Reaction score
- 68
- Location
- USA
- First Name
- Floyd
- Truck Year
- 1969
- Truck Model
- C10
- Engine Size
- 350
Finding a correct fitting can be a nightmare. I had some ramshead manifolds with air injection. Used solid pipe-threaded plugs. I put some anti-seize on them, screwed them in tight, and then cut them off flush with the manifold. Looks great. I should mention that I installed them backwards, screwing them in from the inside of the manifold. The threads are undamaged and they can be easily removed to allow for re-installation of AIR pipes if need be. Didn't want to damage the vintage GM parts. Good luck!
