806, 806YD806, 806YD3”-10”3”-10”

Modification OverviewModification Overview

806- (1979-1988) Cast Iron body- Threaded in 806- (1979-1988) Cast Iron body- Threaded in seats- Internal check parts are epoxy coated seats- Internal check parts are epoxy coated iron.iron.

806YD- (1988-present) Ductile iron body- Bolted 806YD- (1988-present) Ductile iron body- Bolted in seats- Internal check parts are stainless steel.in seats- Internal check parts are stainless steel.

The 806/806YD currently use the ¾” 805YB as The 806/806YD currently use the ¾” 805YB as the bypass assembly.the bypass assembly.

Check Cover RemovalCheck Cover Removal Cover is o-ring Cover is o-ring

sealed.sealed. 3” cover is spring 3” cover is spring

loaded.loaded. * Hold cover firmly * Hold cover firmly

while removing bolts.while removing bolts.

4-10” Loosen bolts 4-10” Loosen bolts ½”. Spring load is ½”. Spring load is now released from now released from the cover and the cover and retained by the check retained by the check assembly.assembly.

* Verify spring load * Verify spring load before removing all before removing all the bolts.the bolts.

Check Valve RemovalCheck Valve Removal Center stem guided Center stem guided

check assembly.check assembly. 3” spring, stem, and 3” spring, stem, and

disc holder are free disc holder are free once cover is once cover is removed.removed.

4-10” disc & spring 4-10” disc & spring subassembly.subassembly.

Slide subassembly Slide subassembly straight out of seat straight out of seat and body.and body.

Check Seat RemovalCheck Seat Removal 806YD series seats are 806YD series seats are

o-ring sealed and bolted o-ring sealed and bolted into the body.into the body.

Remove bolts and pull Remove bolts and pull seat straight out of body.seat straight out of body.

Inspect the plastic guide Inspect the plastic guide bushing in center of bushing in center of seat.seat.

** (806) series seats are ** (806) series seats are threaded into the body.threaded into the body.

Check Disc ReplacementCheck Disc Replacement

Unthread the nut from Unthread the nut from the stem and remove the stem and remove disc retainer.disc retainer.

** For model (806) ** For model (806) spring tension may spring tension may have to be released have to be released to replace disc. to replace disc. Consult service Consult service center.center.

Check Valve Reassembly NotesCheck Valve Reassembly Notes

Reassemble in Reassemble in reverse order.reverse order.

Apply lubricant to o-Apply lubricant to o-rings.rings.

3” Models- inspect 3” Models- inspect and clean the plastic and clean the plastic guide in the check guide in the check cover.cover.