JD PowerBlocks

Powerblocks were sold thru TSC back in the 60’s—70’s.  They increased the Bore and power of the popular JD 2 Cylinders by using a higher compression ratio, aluminum pistons, and a larger bore than stock

 On the top of the PowerBlock is a number — 6-1, 5-2, 7-1, etc.  These numbers represent what model and vintage tractor the block will work in. 

B/50’s were 5” bore

A/60’s were 6” Bore

G/70 were 6.5” Bore
5-1 — 1939-1946 JD B   
5-2 — 1947-1952 JD B   
5-3 — JD 50                 

6-1 — 1934-1946 JD A
6-2 — 1947-1949 JD A
6-3 — 1950 - 1952 JD A and JD 60

7-1 — All JD G
7-2 —JD 70

PowerBlock Sleeves are available individually, or Extreme Tractor Parts can install them in your block.  If ETP installs the sleeves, the block will be cleaned, the old sleeves removed, new sleeves installed, bored to desired bore and honed to fit your (or our) pistons.  The head surface of the block will be decked and any broken bolt/studs removed and retapped.

Powerblock sleeves are available from ETP in the following sizes.  Don’t forget the pistons.  ETP can provide pistons for your “new” block as well.

JD B/50—5” up to 5.25”

JD A/60—6” up to 6.375”

JD G/70—6.5” up to 7.00”