So, my FSM arrived in the mail, and I am working on the 4 barrel. My Cutlass is a M vin. On the drivers side, I see what looks to be a throttle plate control device. FSM shows me this pic. Part is called a Idle Solenoid, with a vacuum one used on a manual transmission. Also found another statement in the FSM saying “not all engines have them”. I am thinking it is to keep the closure of throttle to idle a more gradual event than a snap shut event?




But, looking at my carb I see something like it, but no electrical or vacuum component. Looks like part of it is gone? Can anyone explain this, and what it actually should look like? A part # would be great! Thanks.

 

Yours looks correct for your car, but it looks broken, should have a plunger coming out, yours look like it is missing. Also that top picture, I thing may be on a AC car? Chevy carbs use that type a lot.

 

It's called a dashpot and its purpose is to keep the throttle plate from closing too quickly on deceleration and stalling the engine.

I think you're missing parts of it too. Should have a spring and plunger I think. Here's the original part number from Nov 73 factory parts book. Hope it helps.

 

Thanks men. Yea, it is a factory AC car, and I think the part number you supplied looks correct. 412277. I can find pictures of it, but so far, no supply of them. Nothing I am seeing on eBay and I can usually find stuff there.

 

The item you have is the dashpot. That's what my '72 350 w/ a/c also had on it.
The item pictured in the manual is a step-up solenoid that is wired parallel with the A/C clutch. That causes the plunger to pop out to force a higher idle while the A/C is engaged. All of the '72 carbs had the mounting bosses, but I haven't figured out which cards actually came with the solenoid. They brackets are quite hard to find, and the correct solenoid is *really* hard to find. There are similar solenoids readily available, but they don't have the right plunger.

Post a parts wanted ad on here. There's usually a few of those dashpots hidden somewhere. Note that it's not necessary, so they're usually only used on the perfectly-correct restorations and priced accordingly.

 

The dashpot you have is broken - missing one end of the plunger. Providing you with a "basic" (visual) picture. Not stating this is the correct dashpot for your '72. I replaced the dashpot on my '71 350 cid - they pretty much all look the same but ensure you get the correct part number for your car. The CSM demonstrates the correct adjustment for the dashpot - just follow the really simple adjustment. Basically, you can unscrew the dashpot from the mounting bracket then install (screw in) the new dashpot. Easy-peasy.

 

I will agree! Easy. If you can find one. So far, my search has failed to find one.

 

This is just as an example, and you would need to check to see if would fit your application:

1961-1972 Buick Carburetor Dash Pot | OEM #135721,1191330, 1367231,1371005 | eBay

Anyways I found mine on Ebay for a 1971, it was new. They are a bunch of them. Just be prepared to cross reference. OldGreenPaint's post lists the GM part number. Mine was not GM but old stock aftermarket.

 

Helpful if you stated what model vehicle this Quadrajet is intalled onto.

455 or 350?

 

Trying to assist you in finding one.
This one came up - pricey though for a dashpot. Although, yeah it's NOS...

https://www.2040-parts.com/nos-gm-da...nado-i1333364/

 

I guess I really don't need an answer since every 1971 & every 1972 V8 engine got the exact same dashpot 412277.

 

You guys are good guys. I’m just starting to learn good sources for parts. I know corvettes, that’s my passion. Yea posted this in the small block forum. And this 72 Cutlass has the 350. A factory air car, so limiting idle speed changes is probably needed for that r12 compressor that I have not tried yet. I was told it doesn’t work. Looks like the parts are all there.

 

I have same issue but I am missing the bracket and the dashpot. Does anyone know where to get both?
I ended up having an idol control solenoid added. Thank you all for your help.

 

As oddball noted (above) it's going to be tough finding the bracket. It isn't a carved-in-stone must-have requirement for many normal operating conditions. Your most likely going to need to scavenge some salvage yards to locate a bracket I'm not aware of any reproductions. You might place a Parts Wanted in the classified section possible a member may have one.

 

Interestingly I did a search & supposedly there is a reproduction available...try this

https://www.inlinetube.com/products/...d48747c6d56d2c

 

OPGI has same available...most likely reproduced via inline tube (same as above), but hey...you can spend more money for same one at OPGI.

https://www.opgi.com/air-fuel-delive...s-c241578.html

 

Did you find one? This was just posted:

https://classicoldsmobile.com/forums...0/#post1585795

 

FYI, idle-stop solenoids were used for more than just A/C idle step-up. My '68 2bbl non A/C car uses one to help prevent dieseling by allowing the throttle to more fully close when the ignition is turned off. Tune-up procedure is to unscrew the "hard" idle stop screw until the throttle is on the solenoid (energized) and adjust the solenoid plunger to achieve normal idle speed (~600 RPM in "N" IIRC), then disconnect the solenoid and adjust the "hard" idle screw for ~400 RPM.

 

Thanks for looking out for me VC. I’m working on that one. So busy now. Just dropped the tank today to replace the fuel sending unit. So not watching the forum much.

 

 

So….some of you helped me find a Dashpot on this here very forum! @rickw30 had a Dashpot that he sold me, thank you very much! Complete with a mounting bracket. Appeared to be bead blasted. Function appears to be good. So, bolted it on and had to make a minor bend in the bracket to align the Dashpot plunger with the carb idle tab. Adjusted it so that the Dashpot at full retraction allows the throttle plate to assume idle position. Looks like the Dashpot slows the throttle closure by maybe 2 seconds or so? So I am happy with this outcome. Thanks to all involved.



Installed on the engine.

The old one next to the new one.