A/T - 2ND or 3RD Gear Starts

Number: 83-T-73

Section: VIIC

Date: AUGUST, 1983

Subject: 2ND OR 3RD GEAR STARTS 1983 THM 200-C (HO AND CS MODELS)

TO: ALL CHEVROLET DEALERS


Some 1983 THM 200-C transmissions, HO and CS models only, may experience 2nd or 3rd gear starts. This condition may be caused by a casting flash in the 2-3 T.V. bushing sticking the 2-3 throttle valve.

Follow the service procedure given below when servicing any HO or CS model that experiences this 2nd or 3rd gear start condition. Refer to the service manual for installation procedures of the 2-3 valve train.

FIGURE 1:

SERVICE PROCEDURE:

1. Remove the 2-3 throttle valve bushing from the control valve assembly, (Figure #1).

FIGURE 2 - BUSHING:

FIGURE 3:

2. Inspect the bushing inner diameter for excess casting flash below the large valve diameter at the first slot (Figure #2). The slot surface A must be below the surface of the large diameter (Figure #3).

FIGURE 3:

3. If there is excess flash or a burr present, it may be repaired as follows:

(a) Use a small file (approx. 3/32" 1/2") to remove the excess flash or burr.
(b) Access to this area can be achieved by going through the cast slots with the file (Figure 3).

FIGURE 4 - INSIDE OF THE BUSHING:

(c) File the excess flash or burr completely to flatten the surface (Figure #4). Take care not to file or damage the machined outside or inside diameters of the bushing.
(d) Inspect the repair by inserting the 2-3 throttle valve into the bushing until it bottoms out. Turn the bushing open-end down. If the valve slides out freely, then the bushing has been repaired successfully.
(e) Repeat the inspection several times to insure that the valve is free.
(f) Clean the bushing thoroughly before installing the valve and valve train assembly in control valve assembly.