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THERMOSTAT KIT MERCRUISER GM 142 DEGREE COMPLETE SERVICE KIT 18-3668

$19.05 $22.95

142 Degree Thermostat KIT Original Equipment Mercury( Old Style ) 142 degree thermostat kit fits many different models of Mercruiser raw water cooled marine engines. Fits various Mercruiser V6, V8...

142 Degree Thermostat KIT Original Equipment Mercury
( Old Style )

142 degree thermostat kit fits many different models of Mercruiser raw water cooled marine engines.

Fits various Mercruiser V6, V8 small block and V8 big block raw water engines

    Kit includes:
    18-3551 - 142 degree thermostat
    18-2552 cover gasket
    18-2553 cover gasket
    18-2554 cover gasket
    18-7173 O-Ring and the 18-2917 housing gasket

    • Replaces Mercury 807252Q4, 807252T4
    • Replaces Mallory 9-43150
    • 1981 And Up Standard Cooling with cast iron housing
    • Not for EFI engines!
    • Fits:
      5.7L GM IB, Beginning # B522506 - Ending # B525981 
    • 5.7 GM Ski, Beginning # A338553 - Ending # B514626
    • Mercruiser T-stat # 59137

    Make sure to use the Mercruiser style thermostat and not an automotive style.

    If you use an automotive style it will cause the engine to run very cool on the gauge but your exhaust manifold's will be very hot!