Universal Motors Universal diesel 5416, Service Manual

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Compression release (Release wire is optional parts)
Assemble the parts as shown in Fig. 19. Pull the lever out as
far as it will go. Check to see that the 60
o
angle is attained
and that compression is released. The compression release
is to be used when the battery is low or when starting in cold
weather. To use the compression release, preheat the glow
plug as usual, pull the compression release knob out as far
as possible and hold it there while cranking the engine. This
partially releases the engine compression enabling it to turn
faster in cold weather or when the battery is low. Once the
engine is turning fast enough to start, release the lever and
engine will start.
[[ NOTE ]]
Make sure the compression release has returned to
the operating position by pushing the knob all the
way in.
[[ CAUTION ]]
Do not pull the compression release lever when
the engine is running at high speed or under
load. If it is necessary to use the compression
release while the engine is running reduce the
speed to idle before doing so.
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Adjustment of compression release
1) Set exhaust valve in totally closed position.
2) Remove decompression adjustment window cover from
cylinder head cover.
3) Make valve clearance as “0” with use of decompression
adjust bolt. From this position, turn the bolt further by 1 to
1 .5 turns. Decompression clearance will then be set at
0.030 to 0.044 in. (0.75 to 1.125mm), which is the
designed clearance.
4) After adjusting, be sure to lock adjust bolt securely so that
It will not unturn while engine is in service.
5) Make certain that the clearance is not too wide. To check
this, turn crankshaft by hand and make certain valve disk
does not contact with piston top.
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Top clearance
Top clearance should be 0.028 to 0.035 in. (0.7 to 0.9 mm).
To adjust, use cylinder gasket shims, 0.006 in. (0.15mm)
thick each, onto the head side.
For checking the measurement, place a piece of fuse on the
piston top and fix the cylinder head securely on the cylinder-
head flange. The measurement is taken by the fuse. The liner
is level with the cylinder frame at top surface.
The gasket shims can be reused, so do not lose them.