70/71 Thermactor system

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My 1970 Mark III was missing most of the Thermactor system when I purchased the car. I now have all the pieces and I am in the process of restoration before installation. My question is regarding the control vacuum hose connection to the Air By-Pass Valve. Both the 1970 and 1971 shop manual are extremely light in details for this system. And other sources including on line searches have not yielded much. I know the hose that controls the Air By-Pass Valve gets vacuum from the intake manifold. The 70/71 Thermactor system for both Lincoln Continental and Continental Mark III is the same. From 1972 and on the Thermactor may be the same however some of the parts are different so I don't know if the vacuum connection is different.

Where is that control vacuum hose for the Air By-pass valve connected? Directly to a vacuum tee on the manifold? (Behind the distributor)
Or is it teed into the bottom PVS hose?

And a bonus question, does that hose have a colored stripe?

Thanks in advance.
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[Dan Szwarc]

So... no vacuum diagram? I don't have the vacuum diagrams for 1970 anything. I found the 69 vacuum diagram in the documentation library and it shows no thermactor/bypass connections at all.

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1969 model year Lincoln 460 does not have Thermactor.

I have the vacuum/wiring books for 1971 & 1972. (The huge ones) The vacuum routing shown is only for chassis vacuum circuits. No engine vacuum routing.

The shop manual for those years covers all models for every section. (not the most detailed arrangements) Thermactor is not mentioned in the 1970 shop manual for the 429/460 engine section. (21-07) Nothing listed in Ignition, Fuel or Exhaust. (22, 23 or 25) Nor any mention in the Vacuum Systems section. (37) Which again is chassis vacuum for accessories. There may be a supplement or some other publication For 1970

For 1971 there is as least some details about Thermactor in 429/460 engines section. (21-24-06 & 21-24-07) Component removal and installation with one sketch of a system. That sketch is labeled "Typical", is not configured like a Lincoln 460 (That sketch is of a 302 Boss based on the MPC illustrations) And does not show the vacuum line control routing.

The best detail by far is the 1965-1972 MPC Illustrations 94.1 page 15. It shows the vacuum hose and the routing to an area on the front of the intake manifold. The sketch gets a little busy in that area and I am not sure if the connection is to a vacuum tee or teed into some other intake manifold line.

If I had a pattern to follow I would be done.


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[TonyC]

I didn't know that, actually. I remember reading in some sources that the then-new 460 in 1969 was being touted as the greatest thing since steam power, with exhaust emission control intrinsic to its design and not needing anything extra like a Thermactor system. I guess California had a different take on it and twisted Ford's arm to install Thermactors anyway. So much for superior engineering --but at least the 460 was cheaper to build and lighter overall than the Y-blocks.

That is odd that the 1970 and '71 references have nothing on the Thermactor system. I wonder if it was released in a separate service bulletin that we haven't seen yet...? Anyway, I wish I could help; but the only references I have are for the 462 application. Is the Air By-Pass Valve you mentioned the same as a Backfire-Suppressor Valve, or is it something else entirely?

---Tony

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Thermactor was installed on limited applications mostly to do with engines. 429-/460. California was not a consideration as my Mark III was built in Wixom and delivered to an Ohio LM dealership.
The 1970 applications were more broad than 1971 which I find strange.
In addition other applications got IMCO. (IMproved COmbustion)

While not perfect, for that time period larger displacement engines got Thermactor and smaller displacement engines got IMCO. And some got nothing as far as changing combustion events.

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Gotta hand to Mustang guys. They can get anal.

Thermactor By-pass valve for that era - black ribbed 5/32 hose from the valve to the front vacuum tee on the intake manifold.

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[Dan Szwarc]

Yeah. Probably the same on every ford. No stripe, eh?

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Actually Ford calls it a black stripe from intake manifold to the Thermactor By-pass valve. Which means no stripe.

I do know that Ford is very consistent with vacuum hose color in subsequent years. I think that holds true when they shifted to plastic hose.
PVS hose colors to venturi vacuum - yellow, distributor vacuum advance - green, manifold vacuum - red are the same for all years that used a PVS to control distributor advance.

Which also means for distributors that have vacuum retard (Not A 460 Mark III) that vacuum line is red as well because it is an intake manifold signal. Which either tees into existing PVS vacuum hose for intake manifold vacuum or it comes from a separate vacuum line from intake manifold.

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