Minuteman M220021H13, Operation & Service Manual

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18
MODEL 50 DRY-GAS REGULATOR, CROSS SECTION, PARTS LIST
REGULATOR OPERATION
LP-gas vapor enters at point (A), then passes into primary area
(B) at point (28), where pressure is reduced from up to 250 p.s.i.
at the tank to 4 p.s.i. in area (B). Fuel pressure against diaphragm
(4) overcomes spring (6) and as movement increases, spring (9)
will close lever (10). The primary diaphragm breather (not shown
in drawing), is vented to secondary chamber so that rupture of
this diaphragm would direct fuel into the carburetor.
Fuel now moves through passage (E), past secondary valve (29)
into secondary area (C). As negative pressure (vacuum) is created
at carburetor venturi and is transmitted through dry-gas hose to
chamber (C) atmospheric pressure, exerted through vent hole
(G), forces down secondary diaphragm (18), secondary lever
(24) and spring (22). Fuel will flow in proportion to air velocity
through carburetor venturi, insuring an ideal mixture at all engine
speeds.
Whenever engine is operating, vacuum diaphragm (16) is down
against floor (H) and spring (17) is collapsed. The idle and starting
adjustment is made with tapered screw (27) which regulates the
whisker wire system (not shown), opening up secondary orifice
slightly (but only when vacuum diaphragm is drawn down). Very
little vacuum is needed to start this vacuum diaphragm travel; 0.2”
Mercury to start and 0.5” Mercury for full travel. The instant engine
stops rotating, loss of vacuum in section (D) releases diaphragm
(16), causing bumper (K) to push against secondary lever (24),
overcoming action of whisker wire and insuring 100% lockoff.
This patented Beam design will lock off primary pressures up to
five times in excess of normal, permits starting without priming or
choking.
Order by Part No. NOT by Reference No
Item Part No. Qty. Description
** 60-RBK Kit, Rebuilding
** 60-RCK Kit, Complete
** 60-RK Kit, Repair
1 P3-13 1 Plug, 1/8” Pipe, Hex 1 1
2 50-1 1 Casting, Reg. Body
3 2G-150 1 Gasket with 60-10A
4 60-10A 1 Diaphragm, Primary 1 1 1
5 60-7 1 Cover, Primary
6 60-8 1 Spring, Primary 1 1
7 60-31 1 Retainer Spring
8 60-32A 1 Cap, Retainer
9 60-4 1 Spring, Primary 1 1
10 60-2B 1 Lever, Primary 1 1 1
11 103205-F 2 Screw, Machine 2 2
12 60-5 1 Bridge Primary
13 60-3 1 Pin, Pivot 1 1
14 103210-FS 10 Screw with Lockwasher10 10 4
15 60-29A 1 Orifice, Primary 1
16 60-15A 1 Diaphragm, Vac Lock 1 1 1
17 60-14 1 Spring, Vac Lock 1 1
18 60-22A 1 Diaphragm, Secondary 1 1 1
19 60-23 1 Cover, Secondary
20 103206-P 4 Screw, Machine 4 4
21 60-16 1 Ring, Vac Lock
22 60-17 1 Spring, Machine 1 1
23 60-18 1 Pin, Pivot 1 1
24 60-19B 1 Lever, Secondary 1 1 1
25 60-28 1 Orifice, Secondary 1
26 400-21 1 Spring, Idle 1 1
27 PS-20A 1 Screw, Idle 1 1
NS 103204-P 2 Screw, Machine 2 2