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I had an interesting experience with my hot rod that may be relevant here.

It is a 30-31 Ford Model A Roadster with a 67 SBC 283 (RV cam, HC heads, Delco HEI distributor, and an Edelbrock carb) driving a GM 350 Turbo Hydramatic. It has a 5-blade flex fan and a new aluminum radiator. Car ran fine, idled nicely, ran smoothly, and had great power. It would run nice and cool when moving, regardless of ambient temperature at just below mid-gauge or an indicated 160F. Problem was as soon as I would stop moving the temp would begin to rise quickly and would increase about 30 degrees in a just 5 minutes.

Turns out the problem was the vacuum advance hook-up. The vacuum supply line was connected to the ported outlet on the carb base. This connection would not provide any vacuum to the distributor advance until the throttle plates were opened. I moved it to the vacuum outlet and this seems to have fixed the problem.

I disconnected the vacuum line to the distributor, plugged the outlet, set the engine idle to 750 RPM and adjusted the timing from 10 BTC to 6 BTC. Then reconnected the line and readjusted the idle speed back down to 750 and readjusted the idle mixture screws. I let it idle for 10 minutes and the temp only went up about 5 degrees. I notice that it seems to idle more smoothly and the power also comes on more smoothly. Problem solved and it did not cost me a cent.

We know that retarded or timing not advanced enough will result in over heating and poor performance, and too much advance will result in pinging and detonation. There is no more total distributor advance with the new connection than before, just about 12 degrees more at idle and in full vacuum conditions.

I wonder if this kind of a fix might help our old Packards with higher than normal engine temps while idling in traffic?

Comments?

(o{}o)

Well, I am surprised that this did not generate at least one comment.

I came upon this suggestion when noodling through the Jalopy Journal's H.A.M.B. site. The poster was asking about suggestions for an electric cooling fan because his car overheated when idling, but ran cool while moving. He thought problem was lack of air movement when stopped. Lots of suggestions for fans, and then one poster made the vacuum advance connection suggestion.

(o{}o)

My 1937 ford tudor convertible with a 350 Chevy has the same problem. Always thought it was the original 76 year old radiator (with an electric fan added), but maybe I've to look into this.I've never changed the timing on an engine so I might get some professional help

JW,
My excuse is that you lost me at 67 SBC 283 (RV cam, HC heads, Delco HEI distributor, and an Edelbrock ...

But overheating is a real problem and I am still struggling with the "fluffing" issue, too,...which only occurs when the engine is hot.

My grandkids had a French exchange student living with them for a few days and wanted to take her for a ride in the Packard. Tues, near the end of the away track meet, I picked them up with the top down to take them to the boys la cross home game. 6 pm traffic. On the way we stopped at the local Dairy Queen where they took FOREVER, 4 cars ahead of us, every one of the orders super slow. When I got to the window I could see why...all chiefs. The car heated up to 75%+. Did I want whipped cream? No, thanks, just give me the thing. I can't afford to wait another 15 minutes.

We both cooled down soon after I could get moving again, and yes, I thought it was a matter of getting air through the radiator.

I'm not sure how one person can test the vacuum. I have a compression tester. ...shoot... I just went to the garage to check it and found a sealed can with a Vacuum and Pressure Tester Kit with instructions in French and Spanish. Darn, the exchange student is already gone. I must have the English somewhere. Never been used. So I guess I answered my question...for now.

But with a fitting like the one hooked to the double action fuel pump, I could just make the transfer...as in the photo?

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Joe,

Sorry to have bogged you (and probably many others) down with background description. I thought it would be important to know what kind of engine I was dealing with.

Also, the premise for this fix is that the cooling system is in good operating condition.

It is so aggravating to sit at a long traffic light or be in a long stalled line of vehicles and watch the temp gauge slowly start to creep up and keep on going. Sorta takes the fun out of driving our old Packards, doesn't it?

Yes you can do the definitive test as you describe. You will need to readjust the idle, speed and mixture, as the extra vacuum advance will cause the engine to run faster. It's worth a try. Let us know how it works out.

(o{}o)