View Full Version : Temp running 180 not 160

05-27-2009, 10:12 PM
I have a Maristar 225vrs with the LT-1 motor. I replaced both thermostats as well as the raw water pump imeller, changed the oil and filter before putting it in the water. First time out this Sunday and the motor ran pretty consistantly at 180 instead of 160. When i would accelerate from sitting, it would go down to about 160 then work its way back up while moving. It would occasionally go up above 180.

I bought the t-stats from my local dealer. I did notice that the 160 t-stat i removed was drilled from sides of the housing, probably about a 3/8" hole. The t-stat i got from the dealer was drilled in the middle and had much smaller holes. Not sure if this is signifigant. The label on the package said 160 degree, drilled. Is the drilled t-stat signifigant when the motor is hot or just when it is cold until it opens.

Any suggestions? I am inclined to order a different 160 degree t-stat. One similar to the one i removed.

05-30-2009, 07:27 PM
Well i figured the temp issue out for myself. I put the old t-stat back in and it runs perfect at 160. Dealer is definitly selling the wrong part.

05-30-2009, 07:43 PM
I have also found out that it has to be the exact t-stat for an LT1...always make sure that you have the correct one. sounds like you have it now !