a.Remove ball and spring assembly. Hold ball and unscrew assembly. If dirt or material
b.Use check valve cleanout drill to clean inside of closure screw. Insert the flat- tened end of cleanout drill into opening at end of screw, avoiding spurs in the closure screw. Do not spin drill until the flat on the drill has cleared spurs. Spin drill with your fingers to loosen any buildup, then remove drill and flush inside of screw with gun cleaner. Next, check area where ball seats for dam- age. Also check sleeve for damage; it should fit tightly on the end of the screw. If there is damage or if the sleeve fits loosely, replace it. Replace sleeve if check valve can be threaded all the way into gun block by hand. A good check valve requires the use of a 5/16 in. nut driver to make the last 1/4 turn, com- pressing the sleeve. This compression is required to create an internal seal in the gun block.
c.Remove damaged check valve sleeve. Remove ball and spring. Insert check valve into check valve sleeve removal block (FIG. 24). While holding block, and keeping pressure on head of check valve, slice check valve sleeve with razor knife at a 10 - 15 degree angle rel- ative to the plane of removal block. Remove check valve from block and peel sleeve off. If check valve sleeve remains in gun block after removing
Repair
check valve, use extractor tool to
remove sleeve. Insert threaded end of tool into cleanout port and, while press-
ing tool into gun block, turn it clockwise
several times. Withdraw tool from gun block; sleeve should slide out with tool.
Check Valve Sleeve
Insert Check Valve
FIG. 24: Sleeve Removal Block
d.Insert spring assembly into check valve and turn the screw clockwise. When the spring is fully inserted, stem will jump over spurs in screw and make clicking sound. Ensure ball fully seats in check valve. If not, or ball is damaged, replace with new ball and spring assembly.
14.Remove retaining ring, washer, and felt wiper from retainer. Flush retainer with gun cleaner, insert new felt wiper and washer, then install retaining ring. Loosely thread felt wiper retainer into rear of mixing cham- ber (DO NOT TIGHTEN). If not installing to gun block, store assembly in plastic vial with corresponding cleanout spade.
311320G | 23 |