quadrajet running rich

[achevy1978]

i had a quadrajet rebuilt  and it seemed to run fine then all of a sudden its stataed to run rich and hard to .
i took it all apart it looked ok put it back together and it idles rich.....i have a holly hi volume holley fuel pump
that i think runs at 7.5 lbs. is that to much pressure??

thanks

[Captkaos]

have you adjusted it?  Most Qjets need 5lbs of pressure.

[Stewart G Griffin]

What year is your truck?

Capt., believe it or not, The service manual for my 83 calls for 7lbs of fuel pressure for the quadrajet.

[achevy1978]

78 with a 454
thanks

[Stewart G Griffin]

So, my service manual on pg. 6C-25 calls for all small blocks without vapor return line 7.5 to 9 lbs.

All small blocks with vapor return line 5.5 to 7 lbs.

Big block 7.5 to 9 lbs.

inline 6 4.5 to 6 lbs.

But mine is an 83.

My first question is what is the vapor return line?

i guess time to get a fuel gauge and service manual for 78's?

[Stewart G Griffin]

i meant fuel pressure gauge.

[Boone83K10]

So, my service manual on pg. 6C-25 calls for all small blocks without vapor return line 7.5 to 9 lbs.

All small blocks with vapor return line 5.5 to 7 lbs.

Big block 7.5 to 9 lbs.

inline 6 4.5 to 6 lbs.

But mine is an 83.

My first question is what is the vapor return line?

i guess time to get a fuel gauge and service manual for 78's?

there is a line from the fuel tank to the charcoal canister. that is the vapor return line.