Most original equipment
pistons have deep compression ring grooves.
The GL 901 Spacers have deep walls and should
be used on these pistons.
Some replacement pistons often have shallow
compression ring grooves. The GL 902 Spacers
have a modified wall and should be used on
(TYPE NO. 901)
To install Hastings GL To install
Hastings GL Spacers groove must be Spacers
groove must be cut with Tool Bit as cut with
Tool Bit as shown. shown.
GL Spacer should not project
beyond piston head and may be as much as .020
GL Spacer must always be used ABOVE the compression ring.
If GL Spacer butts at joint
when installed on piston, remove and grind
end until .010" minimum gap is obtained.
Gap of .075" will not hurt.
Can. Pat. No.
U. S. Pat. No. 2365725
If the GL 901 Spacers
are used in shallow groove pistons in place
of GL 902 Spacers, approximately .020"
more stock will have to be removed from the
bottom of the groove, otherwise the spacer ends
Both spacers are listed in Hastings Wholesaler's
Catalog and are available in all popular sizes.