Carter AFB throttle body repairs (formerly Timing 180* out)
- Thread starter Turbogus
- Start date
Turbogus
Active member
On this 9638 it's sort of a rectangular cylinder below the pump jet housing and I don't remember anything in the bottom of the Well except the Pump Plunger Spring. What got me going on this was a post;
"The only place I can think of that there might be a leak is in the accelerator pump. There is supposed to be a one way valve/ball bearing somewhere in the bottom of the pump - if this is missing or stuck open you could have a leak issue". from the Leaking Edelbrock?? - ChevyTalk - FREE Restoration and Repair Help for your Chevrolet
As you can see, I'm going far afield to find a solution for this and I do remain dubious of that ball being in the bottom of the Well, but then again despite having this 9638 for many years, I'm no expert on the AFB.
"The only place I can think of that there might be a leak is in the accelerator pump. There is supposed to be a one way valve/ball bearing somewhere in the bottom of the pump - if this is missing or stuck open you could have a leak issue". from the Leaking Edelbrock?? - ChevyTalk - FREE Restoration and Repair Help for your Chevrolet
As you can see, I'm going far afield to find a solution for this and I do remain dubious of that ball being in the bottom of the Well, but then again despite having this 9638 for many years, I'm no expert on the AFB.
This has turned into a little adventure hasn't it.. Hope you get it!
Turbogus
Active member
I got some vinyl tubing and a funnel and tested the Needle/Seats with the Air Horn inverted (gravity working on the floats) and ran fuel down the line.
The Primary Needle began leaking right away. From the many rebuilds of other AFB's I had a small collection of Needles and Seats
so I swapped out the needle and it held fuel. I don't know if I'm out of the woods yet, but this is just one more thing that was wrong with this 9638.
The Primary Needle began leaking right away. From the many rebuilds of other AFB's I had a small collection of Needles and Seats
so I swapped out the needle and it held fuel. I don't know if I'm out of the woods yet, but this is just one more thing that was wrong with this 9638.
Turbogus
Active member
FINALIZED
Black Betty is on the trail again, idle down to 600, timing set and running smooth....at long last and 136 posts/counter posts, Thanks to all whom have posted their insights and opinions. But for one final pitfall, dropped the throttle return spring and it's lodged somewhere between the body tub and transmission. A quick trip to my best friends' place and it's now FINALLY on track. Now on to the mods before this issue began.
Black Betty is on the trail again, idle down to 600, timing set and running smooth....at long last and 136 posts/counter posts, Thanks to all whom have posted their insights and opinions. But for one final pitfall, dropped the throttle return spring and it's lodged somewhere between the body tub and transmission. A quick trip to my best friends' place and it's now FINALLY on track. Now on to the mods before this issue began.
Turbogus
Active member
Well:bomb: it now comes down to fine tuning. Idle & fast idle speed was a little too high, @ 1000 rpm. back off the two screws to no avail. Upon closer look I found that the linkage for the high speed cam may have been tweaked in the several times I've seperated the Air horn from the Throttle Body. Using needle nose pliers I adjusted the linkage rod slightly to increase it's overall length to get that high speed screw off of the the last step of the cam. I'm doing this incrementally so's not to screw things up any further. Wish me luck!
JPNinPA
Well-known member
Did you have a question about the tube circled in the pic??
Turbogus
Active member
I didn't (Choke Fresh Air Tube) but there was one on another forum that reccomended adding a vertical extention onto the External Bowl Vent to inhibit fuel slosh, but I think he thought this was a Holley.
As security protocols have changed here at work I can no longer log on to my longstanding flicker account not photobucket, so until I can find a photo website that the security programs flip out about I'm using my other longstanding Jeepz account as a surrogate for the limited photos I post of late. Sorry for this incursion.
As security protocols have changed here at work I can no longer log on to my longstanding flicker account not photobucket, so until I can find a photo website that the security programs flip out about I'm using my other longstanding Jeepz account as a surrogate for the limited photos I post of late. Sorry for this incursion.
Turbogus
Active member
Last year, I think it was I posted a thread about and occasional 'spit' through the carburator. Thus began running through the primary electrical system, three rebuilds of the carburator only to find that the intake valve on No. 2 was stuck open by carbon.
Had that taken care of at a machine shop and upon reinstalling the head I noticed that 3 of 4 rocker bridges were bent to the degree that the rocker wasn't making direct contact with the center of the return spring. Reading the FSM about torqing these things incrementally left and right side I thought they may be brittle. With nothing to lose I put the bent ones in a vise and straightened them out with a wrench.
With that done I'm now having a hecofa time trying to get that damm power steering pump bracket bolted on again!
Had that taken care of at a machine shop and upon reinstalling the head I noticed that 3 of 4 rocker bridges were bent to the degree that the rocker wasn't making direct contact with the center of the return spring. Reading the FSM about torqing these things incrementally left and right side I thought they may be brittle. With nothing to lose I put the bent ones in a vise and straightened them out with a wrench.
With that done I'm now having a hecofa time trying to get that damm power steering pump bracket bolted on again!