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10A.4 Thumbscrew (Chart 8 item A4)
10A.4.1 Check Thumbscrew for galled or missing threads. If there are galled or missing threads, replace the Thumbscrew.
10A.4.2 Screw the Thumbscrew into the Jackbars (Chart 8 item A1). If play of the Thumbscrew and the Jackbars exceeds
.010 of an inch, perform repair step 11A.3. If testing in repair step 11A.3 is within tolerance, replace the
Thumbscrew. If testing in 11A.3 the thumbscrew is worn replace the thumbscrew.
10B Main Block Assembly (Chart 7 item B1)
10B.1 Main Block
10B.1.1 Check inside distance between side plates of Main Block. The inside distance between the side plates of the main
block are:
Main Block
Distance
DA-100
1 5/16”
DB-100
2”
DC-100
2”
If the inside distance between the side plates spreads more than a 1/8”, the Main Block (B) should be straighten or
replaced the Main Block. The distance between the side plates should never be less than the above distances
listed.
10B.1.2 Check the Main Block squareness to the pipe by setting the Main Block on a flat surface, as it would sit on a pipe.
The side plates of the Main Block should sit flat on the pipe and should be perpendicular to the flat surface. If the
surfaces are not perpendicular to the pipe surface replace the Main Block.
10B.1.3 Screw the appropriate Thread Gauge (item “E” of equipment required list) into the hole of the Main Block into
which the Thumbscrew (Chart 10 item B7) threads. The Thread Gauge, when screwed into the Main Block should
not exceed .015 of an inch of play when moved in any direction. If the play exceeds the maximum allowable
tolerance replace the Main Block.
Warranty Note: Mathey Dearman Inc. will not warranty or accept any responsibility for heating, welding or
straightening of the Main Block.
10B.2 Chain Adjustment Mechanism (Chart 10 item B2)
10B.2.1 Check the Chain Adjustment Mechanism (Chart 10 item B2) for cracks at the point the chain (Chart 14) contact the
Chain Adjustment Mechanism. If cracks are found replace the Chain Adjustment Mechanism.
10B.2.2 Chain the hole for Socket Head Cap Screw (Chart 10 item B8) in the Chain Adjustment Mechanism (Chart 10 item
B2) for cracks. If cracks are found replace the Chain Adjustment Mechanism.
10B.3 Spring (Chart 10 item B3)
10B.3.1 Check spring to see if it is stretched. If the Spring is stretched, replace the Spring.
10B.3.2 Check the Spring for nicks and dents. If nicks or dents in the spring are deeper than 25% of the diameter of the
Spring wire, replace the Spring.
WARNING:
If the inside distance between the side plates spreads more than a 1/8”, the
Main Block (Chart 10 item B1) should be straighten or replaced the Main Block, The Chain
Lock Pin (Chart 10 item B4) will not insert into the other side of the main block.
WARNING:
Operator injury will result if
the side plates of the Main Block are not square
with each other or there is spreading of the side plates beyond the tolerance specified as the
Main Block will fail to hold the chain during the aligning and reforming process.
