Four Seasons 74601 HVAC Heater Control Valve

OE Quality 60-Day Returns

Heater Valve

Four Seasons 74601 HVAC Heater Control Valve

Brand	Four Seasons 74601
Bypass?	No
Description	Vacuum Open Non-Bypass Heater Valve
Hose Connector Quantity	2 Connectors
Material	Steel
Mounting Hardware Included	Not Included
O.E. Replacement?	Yes
Opening B IN	0.500
Opening B MM	12.700
Opening IN	0.625
Opening MM	15.875
Operation Type	Vacuum
Style	Non-Bypass
Type	Heater Valves
Product line	Heater Valve
Fits	Oldsmobile, Buick, and Pontiac · 40 vehicles

OE replacement. Vacuum-open, non-bypass heater valve for direct service replacement.

Steel construction. Durable material stands up to demanding HVAC use.

Two connectors. Simplifies hose connections for a clean installation.

Cross-references Four Seasons 20205, Four Seasons 74601 and Hayden 5919 for the same application. See all 18.

$52.49Free shipping

In stock · usually ships same day before 1pm CST

Step 1 — Confirm fitment

Free return shipping if it doesn't fit when you check fitment here first.

Select your vehicle to confirm fitment

Verify this part fits before purchasing — free returns if it doesn't

Step 2 — Quantity

Free shipping to the continental U.S.

Free returns within 60 days if it doesn't fit when fitment is verified.

Not what you need? See all HVAC Heater Control Valve options

Four Seasons 74601 Heater Valve Overview

Four Seasons 74601 is a vacuum open, non-bypass HVAC heater control valve built as an OE replacement for classic GM applications. It uses a steel body with two hose connectors and vacuum operation to regulate heater coolant flow in systems that call for 5/8 in. and 1/2 in. port sizes.

This Four Seasons Heater Valve line is focused on direct-fit temperature control components for restoration and repair work. Part number 74601 is used on select Oldsmobile, Buick, and Pontiac vehicles with manual AC or automatic temperature control configurations.

Key Features

Vacuum open operation for heater coolant control
Non-bypass style for the listed HVAC applications
Steel construction for durability in engine-bay service
Two hose connectors
OE replacement design
Opening sizes: 0.625 in. (15.875 mm) and 0.500 in. (12.700 mm)

Fitment Details

Fits 1968-1970 Oldsmobile 98, manual AC; heater valve.
Fits 1968-1970 Oldsmobile Cutlass, manual AC; heater valve.
Fits 1968-1970 Oldsmobile Cutlass Supreme, manual AC; heater valve.
Fits 1968-1970 Oldsmobile Delta 88, manual AC; heater valve.
Fits 1968-1970 Oldsmobile Toronado, with 5/8 in. and 1/2 in. NPT port sizes; heater valve.
Fits 1968 Buick Riviera, manual AC; heater valve.
Fits 1967 Buick Skylark, over engine; manual AC or ATC (Automatic Temperature Control); heater valve.
Fits 1964 Oldsmobile 98, with 5/8 in. and 1/2 in. NPT port sizes; heater valve.
Fits 1960 Oldsmobile 98, with 5/8 in. and 1/2 in. NPT port sizes; heater valve.
Fits 1961-1963 Oldsmobile 98, heater valve.
Fits 1958-1959 Oldsmobile 98, heater valve.
Fits 1962-1963 Oldsmobile Cutlass, with 5/8 in. and 1/2 in. NPT port sizes; heater valve.
Fits 1961-1962 Pontiac Bonneville, with 5/8 in. and 1/2 in. NPT port sizes; heater valve.
Fits 1961-1962 Pontiac Catalina, with 5/8 in. and 1/2 in. NPT port sizes; heater valve.
Fits 1962 Pontiac Grand Prix, with 5/8 in. and 1/2 in. NPT port sizes; heater valve.
Fits 1961-1962 Pontiac Tempest, with 5/8 in. and 1/2 in. NPT port sizes; heater valve.

Common Repair Uses

Restoring heater control on a classic Oldsmobile 98 or Cutlass
Replacing a leaking or sticking vacuum heater valve
Correcting inconsistent cabin heat on Buick Riviera or Skylark applications
Addressing coolant flow issues in Pontiac Bonneville, Catalina, Grand Prix, or Tempest HVAC systems
Replacing an OE-style valve on manual AC or ATC-equipped vehicles

Installation Notes

Verify hose connector size, port size, and vacuum-actuated operation before installation. This valve uses two hose connections and does not include mounting hardware. Confirm the vehicle’s HVAC layout and original valve style match the listed fitment before replacing the part.

Quality Assurance

Four Seasons 74601 is an OE replacement heater valve built for the listed factory applications. Cross-reference part numbers include Hayden 5919 and Quality-Built 15116 for the same application.

This part fits 40 vehicles

Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

Year	Make	Model	Submodel	Liters	Cylinders	Position	Notes
1970	Oldsmobile	98	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1970	Oldsmobile	Cutlass	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1970	Oldsmobile	Cutlass Supreme	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1970	Oldsmobile	Delta 88	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1970	Oldsmobile	Toronado	—	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1969	Oldsmobile	98	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1969	Oldsmobile	Cutlass	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1969	Oldsmobile	Cutlass Supreme	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1969	Oldsmobile	Delta 88	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1969	Oldsmobile	Toronado	—	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1968	Buick	Riviera	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1968	Oldsmobile	98	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1968	Oldsmobile	Cutlass	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1968	Oldsmobile	Cutlass Supreme	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1968	Oldsmobile	Delta 88	—	—	—	N/A	Fits models with Manual AC.; Heater Valve
1968	Oldsmobile	Toronado	—	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1967	Buick	Skylark	—	—	—	N/A	Over Engine; Manual AC or ATC (Automatic Temperature Control); Heater Valve
1964	Oldsmobile	98	—	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1963	Oldsmobile	98	—	—	—	N/A	Heater Valve
1963	Oldsmobile	Cutlass	—	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1962	Oldsmobile	98	—	—	—	N/A	Heater Valve
1962	Oldsmobile	Cutlass	—	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1962	Pontiac	Bonneville	Base	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1962	Pontiac	Bonneville	Custom	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1962	Pontiac	Bonneville	Safari	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1962	Pontiac	Catalina	Base	6.4L	V8	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1962	Pontiac	Catalina	Safari	6.4L	V8	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1962	Pontiac	Catalina	Ventura	6.4L	V8	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1962	Pontiac	Grand Prix	—	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1962	Pontiac	Tempest	Safari	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1961	Oldsmobile	98	—	—	—	N/A	Heater Valve
1961	Pontiac	Bonneville	Base	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1961	Pontiac	Bonneville	Custom	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1961	Pontiac	Bonneville	Safari	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1961	Pontiac	Catalina	Base	6.4L	V8	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1961	Pontiac	Catalina	Safari	6.4L	V8	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1961	Pontiac	Tempest	Safari	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1960	Oldsmobile	98	—	—	—	N/A	w/ 5/8" and 1/2" NPT port sizes; Heater Valve
1959	Oldsmobile	98	—	—	—	N/A	Heater Valve
1958	Oldsmobile	98	—	—	—	N/A	Heater Valve
No rows match your filter.

Directly replaces or cross-references 18 part numbers

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.

Four Seasons — 20205Four Seasons — 74601Hayden — 5919Quality-Built — 151161551072317822463253996795750975895418015131379746660102711174601CWK801513H505H1996WV325