Author Topic: Smog/Thermactor question  (Read 1578 times)

Smog/Thermactor question
« on: January 19, 2022, 10:41:53 AM »

On my 69 GT500, With/A/C, I am getting read to install the thermactor system on the engine.  The pump has been gutted. Do I need any additional block off’s or anything done to the tube that mount to the heads?  Other than assembly, what else do I need to do at this point?

Bob Gaines

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Re: Smog/Thermactor question
« Reply #1 on: January 19, 2022, 10:54:17 AM »

On my 69 GT500, With/A/C, I am getting read to install the thermactor system on the engine.  The pump has been gutted. Do I need any additional block off’s or anything done to the tube that mount to the heads?  Other than assembly, what else do I need to do at this point?
Besides gutting the pump and making it free wheeling the fittings going into the head need to be blocked off. If they are already fixed on the tube as in if they had previously been installed before is one way . The way I have done it many times is I would weld or braze the bottom side ends of the separate fittings and be sure to leave enough hole on the top side so that I could slip the tubes into the holes like normal along with some anti seize compound . That way with a wiggle back and forth and a upward pull they would come out for extra space when removing spark plugs etc.
Bob Gaines,Shelby Enthusiast, Shelby Collector , Shelby Concours judge SAAC,MCA,Mid America Shelby

KR Convertible

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Re: Smog/Thermactor question
« Reply #2 on: January 19, 2022, 11:20:08 AM »
I think Jim Cowles used to sell blank fittings that eliminated the need to weld the tubes.  You could call Jessie and see if he has any.

Bob Gaines

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Re: Smog/Thermactor question
« Reply #3 on: January 19, 2022, 11:49:34 AM »
I think Jim Cowles used to sell blank fittings that eliminated the need to weld the tubes.  You could call Jessie and see if he has any.
Those are used if you are not going to use the tubes or any other smog equipment and just plan on plugging the hole. Those used to be available from Ford years ago. My method is meant to use if you are going to the trouble of making the smog system look functional .
Bob Gaines,Shelby Enthusiast, Shelby Collector , Shelby Concours judge SAAC,MCA,Mid America Shelby

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Re: Smog/Thermactor question
« Reply #4 on: January 19, 2022, 01:19:46 PM »
Sorry, I thought they were hollow so the tube would fit in them snuggly, but not pass air.

Royce Peterson

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Re: Smog/Thermactor question
« Reply #5 on: January 19, 2022, 06:39:51 PM »
I can't see any reason to add more block offs if the check valves are in place and working.
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Bob Gaines

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Re: Smog/Thermactor question
« Reply #6 on: January 19, 2022, 06:47:34 PM »
I can't see any reason to add more block offs if the check valves are in place and working.
One less thing to worry about in case the check valves fail and they are not plugged. ;)
Bob Gaines,Shelby Enthusiast, Shelby Collector , Shelby Concours judge SAAC,MCA,Mid America Shelby

rockhouse66

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Re: Smog/Thermactor question
« Reply #7 on: January 20, 2022, 08:08:53 AM »
I think it makes more sense to block the tubes at the heads as Bob suggested.  Should reduce the heat in the tubes which might burn or discolor the paint.

Special Ed

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Re: Smog/Thermactor question
« Reply #8 on: January 20, 2022, 11:57:29 AM »
The check valves are spring loaded and pulsate when engine is running making a poping noise when hoses are not attached so they need to be capped off if the rest of the smog system is not being used.

gt350hr

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Re: Smog/Thermactor question
« Reply #9 on: January 21, 2022, 10:21:27 AM »
   The disc in the valve is prone to rusting causing a leak . The tubes should be plugged at the head as mentioned.
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