Topic: Want to plug air supply holes in CA -66 289 heads

[fast66]

what is the thread size and is there a preferred plug, or does any plug with the correct thread do?
Thanks,
Claes

[J_Speegle]

Ford had available in their part system a plug made for this purpose with a tapped end to match the base of the hole in the head the same way the smog tubes and those fittings did.  IMHO not very attractive. These plug show up on Ebay from time to time like now. Don't know anything about the seller



http://www.ebay.com/itm/NOS-C6AZ-6052-A-Ford-390-428-Thermactor-Emission-Port-Plugs-Smog-Port-Plugs-/221512806755?pt=Motors_Car_Truck_Parts_Accessories&hash=item3393313163&vxp=mtr

Always found I had more issues when I removed a thermactor system on a 66 - so after a few times I just left them alone if they were already there in the day. But that is likely just me

[jwc66k]

Go to either Google or Yahoo search and put in "c6az-6052-a". We got a set of 8 for a friend under $40 plus about $6 shipping.
Jim

[fast66]

Thanks for the info, guys! Appreciate it.

Any idea of the thread if I should not succeed in finding the original plugs?

br
Claes

[fast66]

Well, I just found almost 2000 of these plugs through www.rearcounter.com
Maybe you all know about this search engine, and if not, it seems very useful.
thanks
Claes

[Texas Swede]

Hej Classe,
When I removed the Thermactor system on my 66 Coupe in the 70's I bought
the plugs in a hardware store in Vällingby. Wish I had kept the complete system
as they are difficult to find nowadays.
Texas Swede

[dave6768]

I know they are a fine thread and from memory I believe are 1/2"-20.

[lancelot66]

Feel like I'm late off the dime here but I'll try and have a definitive answer for you on thread size tonight, after I get home from work. Someone may just beat me to it...1/2 -20 sounds right though.
The ones I have are identicle to the ones Jeff's Link references. They're a perfect fitting part and representation of the original threaded nut and ferrule on the tube ends of the smog system.

[lancelot66]

Yep, dave6768 is right on the money. Thread size of C6AZ-6052-A thermactor plugs are 1/2"-20. Got out my die set to be sure and that size die screws right on it, no issues.

[fast66]

Thanks for the input - would that be a conical thread such as NPT?
//Claes

[lancelot66]

Good question. On the plug, yes, it appears to be that way. Die threads up about halfway, then tightens and stops. On the threaded nut that slides over the tube, butting up against the ferrule at the end, appears to be a straight thread with no taper. Sounds like you won't be going this route though and staying with the plugs.

[jwc66k]

I "inherited" several small block smog heads from a friend who was going to toss them. Two with hardware store plugs had a few of the plugs frozen in place making the heads junk, I couldn't get the plugs out. The ones with the Ford plugs were salvageable and several were reused. Bottom line, use the Ford plug. I found many priced under $4 using Yahoo search.
Jim

[jwc66k]

Thanks for the input - would that be a conical thread such as NPT?
//Claes

No, standard thread. Use the Ford plug.
Jim

[fast66]

Thanks Jim, and all - I will buy the ford plugs.
br
Claes

[fast66]

ok, one final question - the packages in the pictures above are of 6 plugs each - isn't there one hole per cylinder (that is I need 8 plugs) or are there any more holes to plug that I have missed?
Maybe these kits fit several engines (i suppose)...

/C