5.7L Rochester carb issue we think

[mr300z87]

The carb body and parts have been soaking in carb cleaner and I'll be going through them later today to make sure all passage ways are clear and all moving parts are moving. Then when time permits I'll head over to his place to install and run it. My last carb rebuild was on my Weber/Carter carb from the 7.4L in my boat which I seem to like better than this confusing thing. But I am kinda biased since I have been wrenching on my Plymouth with a Carter avs carb for 20 plus years. We shall see how it goes. All have a great weekend. Mike

 

[NHGuy]

Yes the AVS/WFB has fewer moving parts to deal with. But a Qjet is awesome because it corrects more precisely as you go through the rev and torque ranges.

I have a thought on the sticking secondaries. Could be that the return spring is off it's pivot and interfering with the secondary pivot. Flip over the upper air horn. It's accessed with a torx bit and a smallish straight blade driver tip. The torx releases the adjuster and the straight blade turns it. What can happen is the spring falls off the pivot on the other end of the screw-head looking piece. When you put it back together set the tension at 3/4 turn from zero.
If I'm wrong, no big deal, but it's still wise to check the spring tension. HTH

 

[airdvr1227]

Try this simple test. Next time it starts missing loosen the fuel cap. You could have a clogged vent. Spent the better part of the season last year chasing the same symptoms.

 

[mr300z87]

We thought that too and the first thing we did when it started to sputter was remove the filler cap. It made no difference. I still have not finished putting the carb back together yet, but while I was cleaning and inspecting I noticed the one of the secondary,entering rods was bent and the attaching mechanism was also slightly bent. We will see how it runs as soon as I can get to it. Work really is s pain and prevents me from doing fun stuff.

 

[mr300z87]

Question for all the Q-Jet guys out there. The carb is still not back together as my own projects are more important right now, but the other day I started to do a visual check and final cleaning of all the passages when I noticed the the secondary throttle plates were not opening all the way? I figured that at WOT both the primary and secondaries should be straight up and down. IE 90 degrees to the throttle body (lower section of the carb). According to the the rebuild directions there is an adjustment for when the secondary plates open but I can not seen to figure out how to adjust them to open all the way. I am at work now but could provide a photo later tonight to show what I am talking about. I cant wait to get this thing off my work bench Thank in advance for any advice.