Plugging smog holes in heads....

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318willrun

318willrun

Utube channel 318willrun
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Means I was actually plugging smog ports this afternoon, I thought I'd shoot a quick video because I've seen questions asked about this here on this site. I know most already know how, but it might help somebody.
P.S. - I worked with one hand while videoing with the other.. LOL
 
:thumbsup:
About to do this with my 318.
Make tapping easier, thread a nut on it, stick it in a vice then tapa nut on over the square, then you can use a socket.
I bought a bunch of loose taps,1/2 of them had hex nuts pushed over the square ends.
 
They make sockets that fit right on the end of a tap. They are made for square end pipe plugs.
 
Nice Job!

NAPA made a tap like self tapping stud years ago with a female hex on the end to drive it. You put high temp RTV on it, drove it in and broke it off. I have not been able to find them in quite some time. They were very convenient.

I bet Tim @Abodybomber might remember them.
 
RustyRatRod said:
Nice Job!

NAPA made a tap like self tapping stud years ago with a female hex on the end to drive it. You put high temp RTV on it, drove it in and broke it off. I have not been able to find them in quite some time. They were very convenient.

I bet Tim @Abodybomber might remember them.
Click to expand...
Actually no ,Rob... Very cool sounding,I will ask Steve. ( Started to modify Mopar back in '68 ' excellent cylinder head guy.).
 
MoparMike1974 said:
They make sockets that fit right on the end of a tap. They are made for square end pipe plugs.
Click to expand...
There are also tap sockets. I have them,but different tap manufacturers make different square sizes. The pressed on nut is very simple and handy. Except they wont fit back in the case.
 
My dad bought me a ratcheting "T handle" a few years ago, I do not know where he bought it at, but it well made, and slick when using a tap.
 
Most all of the tool manufacturers have 8 point sockets that work very well in the 4 point end of a tap.
 
As cheap and dirty as it sounds, i just used a mig welder to seal mine shut with a quick plug weld.
No leaks, and i was done in under 10 minutes for both heads..........
 
Dartnut said:
As cheap and dirty as it sounds, i just used a mig welder to seal mine shut with a quick plug weld.
No leaks, and i was done in under 10 minutes for both heads..........
Click to expand...
which is fine if you have a welder available
but if you need to go out and buy the stuff, a tap and setscrews are a lot cheaper then a migwelder
 
318willrun said:
Means I was actually plugging smog ports this afternoon, I thought I'd shoot a quick video because I've seen questions asked about this here on this site. I know most already know how, but it might help somebody.
P.S. - I worked with one hand while videoing with the other.. LOL
Click to expand...



The only thing I do different is I blow air into the exhaust port to blast the chips from the tap back out the hole before I put the plug in.
 
Jadaharabi said:
The only thing I do different is I blow air into the exhaust port to blast the chips from the tap back out the hole before I put the plug in.
Click to expand...
I clean the holes out IF the heads are off. I won't blow air in there with the heads already on the engine. If a shaving is blown on the exhaust valve, it could fall in while the motor is cranking to start.
 
Dartnut said:
As cheap and dirty as it sounds, i just used a mig welder to seal mine shut with a quick plug weld.
Click to expand...
If the heads are off, would it be best to put the weld on the inside of the head, which would decrease the air volume slightly? Or might the heat soften the infused hardening of the head (e.g. w/ a ...302 head)?
 
Richard Sweet said:
If the heads are off, would it be best to put the weld on the inside of the head, which would decrease the air volume slightly? Or might the heat soften the infused hardening of the head (e.g. w/ a ...302 head)?
Click to expand...
IMO, while probably the best way since it’s a super permanent deal, it’s overkill - which isn’t a bad thing. I’ve seen people use JB Weld and even aluminum foil crammed in there really good.

The welding should be ground down if it’s any high. But no, the volume decrease isn’t anything that would show anywhere and NO, port velocity wouldn’t pick up. If it did, that would be about a 1/4 inch of welded.
 
I forgot about this thread... LOL I hope it's helped somebody
 
Richard Sweet said:
If the heads are off, would it be best to put the weld on the inside of the head, which would decrease the air volume slightly? Or might the heat soften the infused hardening of the head (e.g. w/ a ...302 head)?
Click to expand...
The heads were on, and my thought was that the remainder of the hole would just fill up with carbon as time went on.
And yes, I ground the surface and filed it flush with the port...
 
I wouldn't think that a mig weld would stick very well to cast iron
I've done the tap and screw in Allen headed setscrews before on this job before...
 
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