Valve Guides, Replacing; Valve Seats, Replacing - Volvo Penta TAD1630G Workshop Manual

Service procedures - engine

Valve guides, replacing

Special tools: 999 1083, 999 8336
1
Press out the valve guides using tool 1083.
2
Oil the new valve guides and press the guides into the cylin-
der head using drift 999 8336. The tool installs the guides at
the correct height above the cylinder head surface. The
same tool is used for all valve guides.
Note: The guides for intake and exhaust valves should have
the same short chamfer pointing up. Intake valve guides (A)
should have their long chamfer pointing down.
3
Ream valve guides if necessary.
28

Valve seats, replacing

Special tools: 999 2479, 998 9876
The valve seat must be replaced when measurement "A",
measured with a new valve, exceeds 1.0 mm.
This measurement applies to both the inlet and exhaust
valves.
Remove the old valve seat by cutting two diametrical notch-
es in the seat and cracking it with a chisel.
Note: Be careful not to damage the cylinder head.
Thoroughly clean the seat location and check the cylinder
head for cracks.
Measure the diameter of the valve seat location. With this
measurement as a basis, check whether a standard size
seat or an oversize seat is required. Machine the valve seat
location if necessary.
Cool the seat in carbon dioxide snow to minus 60- 70°C
(140-158°F) and heat the cylinder head by hosing it with hot
water or some other suitable source of heat. Press in the
seat using a drift.
Machine the seat to the correct angle and width.
Group 21