Reed Block - Mercury 15XD Service Manual

POWERHEAD
MEASURING PISTON
1. Measure piston skirt at right angle (90° ) to piston pin centerline.
20/25/20 JET
PISTON CLEARANCE

Reed Block

IMPORTANT: DO NOT remove reeds from reed block except for inspection pur-
poses only. DO NOT turn used reeds over for reuse. If a reed block component is
damaged, the entire reed block assembly must be replaced. Individual compo-
nents are not sold separately.
1. Thoroughly clean reeds and reed block.
2. Check for wear (indentations), cracks or grooves on sealing surfaces of reed block
that could cause leakage.
3. Check for chipped or broken reeds.
4. Inspect reed block seal for swelling or looseness. Replace reed block assembly if nec-
essary.
5. If reeds have been removed, retorque screws to 25 lb. in. (2.8 N· m). Check reeds as
outlined in " Reed Opening"and " Reed Stop Opening"following
Page 4-32
Standard Piston Diameter
2.5583 in-- 2.5593 in. (64.98 mm -- 65.00 mm)
MINIMUM BORE MEASUREMENT
-- MAXIMUM PISTON MEASUREMENT
= PISTON CLEARANCE
PISTON CLEARANCE
0.003 in. -- 0.004 in.
(0.076 mm -- 0.101 mm)
0.50 in.
(12.7mm)
57106
90-826883R2 JUNE 1998