Packard Forum Index » Post-War (1946-54)

Hello! The 52 200's 327 inline doesnt seems coldblooded ,The carbs a recent rebuild (merrit) so I figure the choke works;I dont get a fast idle when starting ,it just starts and idles at a normal speed even though its cold ,normal for these cars? The flap in the exhaust manifold that is controlled by a thermostatic spring is frozen in place and the spring is missing .This shouldnt affect the cold idle or choked idle but I want it to get working
I was wondering if anyone had any good tips on how to free it up without hurting anything ,I tried some penetrating unfreeze spray stuff and some gentle repeditive tapping ,I torqued on the counterweight a bit ,Im hoping its frozen in a advantageous position .And I was hoping that if I just keep rapping on it and adding unfreeze it might loosen up some year

In the Literature section, Service manuals for 51-54, at the end of the Engine section, there are some trouble shooting steps. (part of the page attached mentioning heat control valve)... earlier manuals suggest loosening it with kerosene and working it back and forth, plus tightening the spring so the flap can (is forced to) return to the closed position when the engine cools.

Attach file:

---

  (81.14 KB)

Spraying liberally with PB Blaster and then using a drift against the pin, drive it in a little. If you have the manifold off you could drive the pin back and forth. If you are hitting the counterweight to try and turn the pin you will just break it.

Yes I tried to free up the shaft on my car by using some light hammer taps on the counterweight and sure enough it broke. Don't do this.

oh boy thank you for the valuable advice ! Ill quit tapping on the counterweight ! Ill continue to tap on the other end and Ive already been using the super penetrator ,maby if i keep asking it itll loosen up some day ! Is there a way to judge if the flap is pointing the right way based on where the counterweight is stuck? IE am i frozen in the right spot
My weight seems to be in a horizontal position relitive to the pivot point

Dear steve:

You may be able to free the valve by soaking and lightly tapping over a period of weeks. So be patient.

You can also carefully heat the unit with a torch. I think a Mapp gas torch would be more effective than propane. You can ask the hardware store about that.

Thermostat springs are available and you can just use one from Chevy if cost is a concern.

Generally, the weight should be in the 11 O'clock position when closed. However, for the unit to work efficiently the manifold really needs to be disassembled and all the carbon removed from inside the unit. You can judge whether your unit is open by feeling the manifold during warm up. If it is getting warm above the shaft faster than below the shaft it is probably stuck closed.

If it is stuck open that is better than it being stuck closed.

Do NOT tap on the weight ANY whatsoever. Standard, generaly accepted and widely used procedure is to tap at the END of the shaft that sticks out on the OPPOSITE side of the weight and to tap on the end of SHAFT just UNDER the weight.

i.e. drive the shaft backwards and forwards by tapping PARALLEL to the shaft at the ENDS of the shaft on each side.

BOTH ends of shaft are accesible on my 1948 2262 288 exh manifold. THis is true of most applications.

I read somwhere that a product from GM works. I have a sprayy can however I haven't tried it yet. The PN #88862627, It is called Rust Penetrant & inhibitor, Heat Valve Lubricant.

I am going to use it whenn I get around to putting mine back together.

Fred D