2) Valve Guides; 3) Valve Seats; 4) Valves - Rotax 914 F Maintenance Manual

14.5.2) Valve guides

See Pic. 246 and 241.
Check diameter of valve stem
Q and int. dia. of valve guide
W (dimension p and dim. o):
If wear limit is reached, renew
valve guide.
For this procedure sent the
cylinder head to an author-
ized overhaul facility.
Dimension
new
See Wear Limits, Chapter 15).

14.5.3) Valve seats

See Pic. 248.
Ensure that the sealing faces Q of valve
seats are clean. If need be, relap using
emery paste, see Chapter 11.7.16). Check
sealing face width, dimension [, see
Chapter 15). At presence of burned spots
or deformation, send cylinder head for
overhaul to an authorized overhaul facility.
Dimension
See Wear Limits, Chapter 15).

14.5.4) Valves

See Pic. 249.
Clean valves and check valve
head Q for wear. Place valve
on V-blocks W and check valve
head out-of-true with dial gauge
(max. admissible out-of-true,
measured on valve head, see
dimension ] in Chapter 15).
Sealing face of valve head is armoured. Therefore do not rework valve head.
However, seal-lapping with emery paste is allowed, see Chapter 11.7.16).
Renew valve as required. Minimum rim thickness R 1,2 mm (0,047 in.).
Check retaining grooves T on valve stem. Check valve cotters, replace if
necessary.
The exhaust valves (dia. 32 mm = 1,3 in.) are thermally higher stressed and
therefore should be particularly checked. Seal-lap both valves and check for
leakage.
Modification no.
- 0 -
00279
new
00284
Reference
1
2
00281
Pic. 246
wear limit
1
45°
wear limit
3
1
2
Pic. 249
Main Date
1997 02 01
914 F
Maß /
dim.
Pic. 247
00285
Pic. 248
4
1,2 mm
0,472 in.
Page
249