750-91 (revised 2009)
Model CB-LE Packaged Boiler Manual
8-19
8.18 — Fuel Oil Metering Valve, Adjusting, and Relief Valves
If replacement of the metering valve packing is necessary, procure kit P/N 880-370 and install:
FIGURE 8-7. Metering Valve Packing Sequence
1. Shut off the oil flow. Be sure no pressure shows on the gauge.
2. Match-mark the cam hub and drive shaft. Match-marking will enable replacement of the cam in its original posi-
tion and result in a minimum of cam adjustment when the burner is refired.
3. Clamp or hold the metering stem in the down position.
4. Loosen the setscrews in the cam hub and rotate, or move the cam to a position where it does not interfere with
stem removal.
5. Withdraw the metering valve stem and spring. Do not drop or mishandle. Check for nicks or scratches. Check
that the pin holding the metering portion is not protruding. Back off the packing gland.
6. Remove the capscrews holding the jackshaft support bracket so that the bracket can be moved. It may also be
necessary to loosen the supporting bracket on the far end of the shaft.
7. Remove the existing packing and guides. Do not reuse the packing and guides.
8. Lightly coat the stem with the lubricant provided with the packing kit. Place the new packing, O-rings and
guides onto the stem in the sequence shown in Figure 8-8. The beveled face of the guides and the teflon rings
must face upward, with the exception of the upper brass guide which is facing down. Be sure that the O-rings
are properly located.
9. Using the stem as a guide, insert the assembled packing into the cavity, then withdraw the stem.
10. In the event the packing is too high, remove one teflon packing from each side of the middle brass guide as
needed.
Under no circumstance eliminate the two teflon packings on only one side of the brass guide.
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