carb question on m4me quadrajet - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Jeramy · 09-22-2015, 09:36 PM

I have been running my truck on ported vacuum(passenger front corner) and after much reading and talking to local builders went to switch it to manifold vacuum(front drivers side) only to find that it also has no vacuum at idle also.

Carb is m4me quadrjet number 17084290. stock carb for 81 c10 with 350/auto.
Any suggestion or should i return it under warranty and try with another one?

any and all help appreciated and thank you in advance.

geezer#99 · 09-22-2015, 10:59 PM

Might be you have the wrong carb gasket and it's covering the port in the base.
Have you checked the other ports?
You might need a vacuum tree behind the carb.
https://www.paragoncorvette.com/c-22...aspx?pagenum=1

Jeramy · 09-23-2015, 07:52 AM

i used gasket recommended for application by felpro but still a possibility. i do get strong vacuum from it off idle just none at idle.

enaberif · 09-23-2015, 09:07 AM

Do manifold vacuum off the port behind the carb on the intake manifold. you may need to put a nipple in its spot.

Jeramy · 09-23-2015, 08:27 PM

will try that this weekend

09-22-2015, 09:36 PM	#1
Jeramy Registered User Join Date: Dec 2014 Location: Mulberry, AR Posts: 222	carb question on m4me quadrajet I have been running my truck on ported vacuum(passenger front corner) and after much reading and talking to local builders went to switch it to manifold vacuum(front drivers side) only to find that it also has no vacuum at idle also. Carb is m4me quadrjet number 17084290. stock carb for 81 c10 with 350/auto. Any suggestion or should i return it under warranty and try with another one? any and all help appreciated and thank you in advance. __________________ 1981 Silverado C10 LS/4l60e My truck may be loud and ugly but I love her like bacon

09-22-2015, 10:59 PM	#2
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,733	Re: carb question on m4me quadrajet Might be you have the wrong carb gasket and it's covering the port in the base. Have you checked the other ports? You might need a vacuum tree behind the carb. https://www.paragoncorvette.com/c-22...aspx?pagenum=1

09-23-2015, 07:52 AM	#3
Jeramy Registered User Join Date: Dec 2014 Location: Mulberry, AR Posts: 222	Re: carb question on m4me quadrajet i used gasket recommended for application by felpro but still a possibility. i do get strong vacuum from it off idle just none at idle. __________________ 1981 Silverado C10 LS/4l60e My truck may be loud and ugly but I love her like bacon

09-23-2015, 09:07 AM	#4
enaberif Registered User Join Date: Jan 2009 Location: Calgary, AB Posts: 1,181	Re: carb question on m4me quadrajet Do manifold vacuum off the port behind the carb on the intake manifold. you may need to put a nipple in its spot.

09-23-2015, 08:27 PM	#5
Jeramy Registered User Join Date: Dec 2014 Location: Mulberry, AR Posts: 222	Re: carb question on m4me quadrajet will try that this weekend __________________ 1981 Silverado C10 LS/4l60e My truck may be loud and ugly but I love her like bacon



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.