Fixing a Holley Qjet
01-12-2007, 11:25 PM
#1
Race Director
Thread Starter
Fixing a Holley Qjet
The Qjet on the 77 I started using last summer is the correct Qjet for the car, but was rebuilt by Holley before I got the car. The secondary throttle plate wouldn't open at all and not having time to fool with it I just put it on the shelf for a while. Finally put a kit in it a couple weeks ago and found that the secondary gasket had split and prevented the secondaries from opening. Holley also had epoxied the well plugs.
After the kit etc it ran pretty well, but since the PO had put on an intake and headers, it was lean throught the range. I put in different jets and rods. It was also hard starting in the mornings, so while on the car, I took the air horn off in the morning and found only 1/4" of gas in the bowl. Lifted the carb up carefully and saw a drip ready to let go from each well plug. The intake plenums were also pretty moist. Tapped and JBWelded 8-32 screws in and reinstalled. The next morning, just for fun, I did it again and same thing.
This time I pulled all the lead out with the 8-32 screws and tapped for 10-32. This time there was no lead left in the bore and the 10-32 starter tap worked perfectly in the original bore without drilling.
Also this time also used a gasoline resistant epoxy putty on the threads, not the prettiest, but all I could get on short notice. Would have preferred to use a more creamy product.
Also tapped for a stainless allen set screw for the APT adjustment access.
Made an adjustment tool, so that the APT stop can be adjusted without any carb disassembly.
Also while I was at it, I made a return/relief tee for the fuel line (since the PO had put on a single port pump) and filled and drilled the return tube to .035", hopefully to limit the pressure to the needle and seat.
Leaking well finally solved. Played with the APT a little, but am currently driving around with a vacuum gauge taped to the windshield. Steady 20" at idle and 17- 18 at 2500rpm cruise.
For no more than it took, I'm happy I did the extra steps and would recommend this if you happen to have the carb apart.
After the kit etc it ran pretty well, but since the PO had put on an intake and headers, it was lean throught the range. I put in different jets and rods. It was also hard starting in the mornings, so while on the car, I took the air horn off in the morning and found only 1/4" of gas in the bowl. Lifted the carb up carefully and saw a drip ready to let go from each well plug. The intake plenums were also pretty moist. Tapped and JBWelded 8-32 screws in and reinstalled. The next morning, just for fun, I did it again and same thing.
This time I pulled all the lead out with the 8-32 screws and tapped for 10-32. This time there was no lead left in the bore and the 10-32 starter tap worked perfectly in the original bore without drilling.
Also this time also used a gasoline resistant epoxy putty on the threads, not the prettiest, but all I could get on short notice. Would have preferred to use a more creamy product.
Also tapped for a stainless allen set screw for the APT adjustment access.
Made an adjustment tool, so that the APT stop can be adjusted without any carb disassembly.
Also while I was at it, I made a return/relief tee for the fuel line (since the PO had put on a single port pump) and filled and drilled the return tube to .035", hopefully to limit the pressure to the needle and seat.
Leaking well finally solved. Played with the APT a little, but am currently driving around with a vacuum gauge taped to the windshield. Steady 20" at idle and 17- 18 at 2500rpm cruise.
For no more than it took, I'm happy I did the extra steps and would recommend this if you happen to have the carb apart.
