Another dumb question by me thermostats
 

Ok I have a 1988 150 mercury out board and have to change the two thermostats that I did 100 times before my dumb question is this the thermostat on one side it goes in yo the block the other side fits into the hose housing it comes with a rubber seal/ gasket the seal is longer on one side ,does the longer side go towards the block or the hose housing I have been doing this for along time and ever time I do it I don't know if I'm putting the seal in right, I hope you can understand what I'm saying, I'm not even sure if it would make a differance Thanks for any reply I know it's not to important but I'm wondering how many are not sure like me thanks again

best remember, the spring goes toward the block.

don't know if you need to do this or not, but i used to put mine in a pot of water on the stove and bring them up to a boil to make sure they were opening at the same rate. i bought some sierra ones once and they had a wide range of opening. motor still ran hot, so i went back with the mercs because they opened at the same time.

Stick with mercury Gotcha