Inspection And Servicing - BRP Johnson J30TEL4SUA 2007 Service Manual

Inspection and Servicing

Cylinder Head
Remove all carbon deposits from the combustion
chambers. DO NOT use any sharp edged tool to
scrape off carbon. Be careful not to scuff or nick
the metal surfaces.
Check for cracks in the intake and exhaust ports,
the valve seats, the combustion chambers, and
the surface of the cylinder head.
1
2
1. Exhaust valve seat
2. Intake valve seat
Use a straightedge and a thickness gauge to
measure the cylinder head distortion on the gas-
ket surface at six (6) locations as shown.
The service limit for distortion is 0.002 in. (0.05
mm). If any measurement exceeds this specifica-
tion, resurface or replace the cylinder head.
The cylinder head can be resurfaced using a sur-
face plate and #400 grit wet sandpaper. Move the
cylinder head in a figure eight pattern when sand-
ing.
001471
Check the water jackets for clogs or obstructions.
1
001473
1. Water jacket
POWERHEAD
CYLINDER HEAD
001474
001473
001473
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