Engine issue - vacuum related? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

eighteenninetytwo · 07-18-2021, 03:40 PM

Blazer (350 sbc) starts fine, but stalls as soon as I take foot off the gas irrespective of choke position - it will keep running if i rev it but I don't want to do that. Could be vacuum related? I have (what I think is ) an old vacuum canister with two ports, it has one line from the front left side of the Edelbrock carb but the other port on it isn't connected? Should that be connected to something and a tube came off maybe?

I'm pretty new at the engine stuff, just getting into it bit by bit so please excuse me if this is a retarded question. Google tells me this is supposed to hold a vacuum for brakes etc but wondering how it does that with an open port - hence my question.

eighteenninetytwo · 07-18-2021, 05:24 PM

$16 fix for new vacuum canister and cap for the open port. The open port SHOULD go to actuate vents for the heater etc but as I only drive in the spring, fall and summer, and in California the heating isn't an issue. That can re attached next time the dash comes off.

**Corts60** · 07-18-2021, 05:37 PM

That is a vacuum accumulator. For now just put a plug on it and see if your problem goes away. Double check your PCV and brake booster don't have a major leak.

eighteenninetytwo · 07-19-2021, 01:12 PM

Bought a replacement and put a cap on that = all good. A $20 fix including the can of seafoam I got to help clean up any deposits I accumulated driving the thing home with no vacuum. Wish all fixes were this cheap.

**Hart_Rod** · 07-19-2021, 03:08 PM

Quote:

Originally Posted by eighteenninetytwo

Bought a replacement and put a cap on that = all good. A $20 fix including the can of seafoam I got to help clean up any deposits I accumulated driving the thing home with no vacuum. Wish all fixes were this cheap.

Nice. Did you put the seafoam in your gas or down the carb?

eighteenninetytwo · 07-19-2021, 03:32 PM

Both in the Oil and the Gas. Not in the carb - that didn't occur to me actually.

**Corts60** · 07-19-2021, 08:58 PM

Be sure to change that oil out. I wouldn't drive it long at all with the oil thinned out with that stuff.

07-18-2021, 03:40 PM	#1
eighteenninetytwo Registered User Join Date: Sep 2013 Location: Redwood city, CA Posts: 694	Engine issue - vacuum related? Blazer (350 sbc) starts fine, but stalls as soon as I take foot off the gas irrespective of choke position - it will keep running if i rev it but I don't want to do that. Could be vacuum related? I have (what I think is ) an old vacuum canister with two ports, it has one line from the front left side of the Edelbrock carb but the other port on it isn't connected? Should that be connected to something and a tube came off maybe? I'm pretty new at the engine stuff, just getting into it bit by bit so please excuse me if this is a retarded question. Google tells me this is supposed to hold a vacuum for brakes etc but wondering how it does that with an open port - hence my question. Attached Images

07-18-2021, 05:24 PM	#2
eighteenninetytwo Registered User Join Date: Sep 2013 Location: Redwood city, CA Posts: 694	Re: Engine issue - vacuum related? $16 fix for new vacuum canister and cap for the open port. The open port SHOULD go to actuate vents for the heater etc but as I only drive in the spring, fall and summer, and in California the heating isn't an issue. That can re attached next time the dash comes off.

07-18-2021, 05:37 PM	#3
Corts60 Just here to tinker Join Date: Jun 2008 Location: Holland, MI Posts: 3,697	Re: Engine issue - vacuum related? That is a vacuum accumulator. For now just put a plug on it and see if your problem goes away. Double check your PCV and brake booster don't have a major leak. __________________ 78 C10 SWB Diesel #1 (wrecked)http://67-72chevytrucks.com/vboard/s...1978+silverado 78 C10 SWB Diesel #2 (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=650751 60 GMC Suburban (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=445526 60 GMC 1000 (sold)http://67-72chevytrucks.com/vboard/showthread.php?t=298235 67 GMC 1500 (sold) http://67-72chevytrucks.com/vboard/s...d.php?t=803695 73 Chevy C20(Daily)http://67-72chevytrucks.com/vboard/s...d.php?t=852767 86 Suburban(summer unit) http://67-72chevytrucks.com/vboard/s...d.php?t=810697 88 Suburban 4x4(sold)

07-19-2021, 01:12 PM	#4
eighteenninetytwo Registered User Join Date: Sep 2013 Location: Redwood city, CA Posts: 694	Re: Engine issue - vacuum related? Bought a replacement and put a cap on that = all good. A $20 fix including the can of seafoam I got to help clean up any deposits I accumulated driving the thing home with no vacuum. Wish all fixes were this cheap.

07-19-2021, 03:32 PM	#6
eighteenninetytwo Registered User Join Date: Sep 2013 Location: Redwood city, CA Posts: 694	Re: Engine issue - vacuum related? Both in the Oil and the Gas. Not in the carb - that didn't occur to me actually.

07-19-2021, 08:58 PM	#7
Corts60 Just here to tinker Join Date: Jun 2008 Location: Holland, MI Posts: 3,697	Re: Engine issue - vacuum related? Be sure to change that oil out. I wouldn't drive it long at all with the oil thinned out with that stuff. __________________ 78 C10 SWB Diesel #1 (wrecked)http://67-72chevytrucks.com/vboard/s...1978+silverado 78 C10 SWB Diesel #2 (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=650751 60 GMC Suburban (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=445526 60 GMC 1000 (sold)http://67-72chevytrucks.com/vboard/showthread.php?t=298235 67 GMC 1500 (sold) http://67-72chevytrucks.com/vboard/s...d.php?t=803695 73 Chevy C20(Daily)http://67-72chevytrucks.com/vboard/s...d.php?t=852767 86 Suburban(summer unit) http://67-72chevytrucks.com/vboard/s...d.php?t=810697 88 Suburban 4x4(sold)



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.