Hi Everyone,

New here and new to classics. I inherited the family 68' 442 from my Grandma last year (hers since new, she's fine just didnt want to take care of it any more). The car underwent a major frame off resto in the 90's and was in great shape except for the never rebuilt 180k mile engine. Long story short the engine needed a complete rebuild which took a year, two complete attempts and an ongoing lawsuit between my mechanic and the machine shop. The engine is now systematically taking out any week links left among the accessories.

Latest victim is the hot start hot air valve on the air breather (no mechanic around me knows what the part is actually called let alone a part number or source. It's getting vacuum but not closing on a hot start, making hot start very rough, need to pump the gas for a few minutes before it'll clear up.

Any info on the part name, part number, or potential sources would be greatly appreciated!

The part:



The Ride!

 

That's the Thermac door/valve, at least that's what I've always heard it called. If your Olds has trouble starting look at the timing and choke before blaming the inoperative thermac system.

 

Thanks for the info, a mechanic has confirmed that the flap isn't closing when receiving vacuum. Cold start is fine, though it is taking a while to get up to temp. Immediate hot start is fine, but cold day, warmish engine after sitting for half hour is no good. Wants to sputter and die.

 

Check with Fusick Automotive Parts (www.fusickautomotiveproducts.com), part number ACD682, air cleaner vacuum diaphragm. I had to replace the one on my '69. For some reason, the one on my '68 still works!

RandyC.

'68 4-4-2 convertible
'69 4-4-2 convertible

 

Choke motor it’s called. You can get them in AC delco replacements, even comes with a pop rivet, painted glossy black, yours is red, don’t know about that

 

That's awesome, can't find it on AC Delco's site with the P/N, any chance you have a link?

 

And yet, neither the box nor the instructions in the photo you posted refer to it as a "choke motor". Sometimes it pays to just crack open the CSM.

 

Here's a link to the Fusick part:

https://www.fusickautomotiveproducts...?number=ACD682

I couldn't find a part with the AC Delco #219-31 that Burd posted.

 

The original part number for that actuator is 6484246. Search that number and you'll find NOS ones and new replacement ones, like this one.

 

They called it a motor?

 

They also called the Delcotron a "generator", so there's that.

My real point was that the hot air riser valve has exactly nothing to do with the choke, other than both are supposed to operate when the engine is cold. To the OP: the whole point of the thermac hot air system was to allow the engine to improve fuel atomization under cold start conditions in the winter. If this car is a summer cruiser that only gets driven to cruise nights, you'll never miss that system not operating.

 

Thanks everyone for the wealth of knowledge! I'm in the pacific northwest so it's be an any non-rainy day cruiser which means anything from 28-90 Fahrenheit and pretty humid in the cold.