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Thermostat Kit Mercruiser 142 Degree Complete Service Kit 18-3646

$29.60 $35.09


142 Degree Thermostat KIT - Sierra

142 degree thermostat kit designed to fit many different Mercruiser raw water cooled marine engines.

Kit includes 18-3551 142 degree thermostat, 18-2917 housing gasket, 18-2844 cover gasket, 18-2553 cover gasket and 18-2834 cover gasket

Kit includes:
18-3551 - 142 degree thermostat
18-2917 housing gasket
18-2844 cover gasket
18-2553 cover gasket
18-2834 cover gasket

  • Replaces Mercury 807252Q3
  • Replaces Mallory 9-43151
  • Fits Mercruiser model 215 Ford 302 CID raw water cooled engines from 1971 to 1972 with serial number range 3040411 to 3385720
  • Fits Mercruiser model 228 GM 305 CID raw water cooled engines from 1977 to 1980 with serial number range 4765100 to 5907057
  • Fits Mercruiser model 255 GM 350 CID raw water cooled engines from 1975 to 1980 with serial number range 4175500 to 5907057
  • Fits Mercruiser model 260 MIE GM 350 CID raw water cooled engines with serial number range 0B522506 to 0F024999
  • Fits Mercruiser 7.4 MIE GM 454 CID raw water cooled engines from 1988 to 1992 with serial number 0B788366 to D715493

    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!