View Full Version : Running boat with no Thermostat?

05-29-2009, 08:40 PM
When I put my 87 PS190 up for the winter I pulled the old t-stat with the intention of getting a new one. I thought I could pick one up a the auto parts store, but the lowest they have is a 195*. Can I run the bought without a t-stat until I get a new one from SKIDIM, next week? The one I pulled out showed that it was a 180* is that too high also for a 87 351 indmar?

05-29-2009, 08:43 PM
My 87 PS190 runs at 160..... You can run with out a stat, should run colder.... I have done this in a car to get home...

05-29-2009, 08:48 PM
Looking at SKIDIM's sight I figured 160 was the correct one, I bought it last year and ran it all summer with the 180 in there, from the previous owner.

05-29-2009, 08:57 PM
This is what you need, http://www.skidim.com/prodinfo.asp?number=R026002E

05-29-2009, 09:14 PM
Thanks No1-I will be okay running it for day without one, correct?

05-29-2009, 10:22 PM
I don't think it will be an issue. Most days my boat runs under 140 in the mornings and might hit 160 later in the day.

If anything just some carbon build up on the plugs.

05-29-2009, 10:59 PM
I used to run my 88 ps190 with out one all the time. Not recomended, but it ran better and with one it burnt up starter solenoids....yeah....I sold that one and got a newer one8p

05-29-2009, 11:23 PM
'Preciate it Guys.

05-30-2009, 12:51 AM
I had to replace my thermostat here a few weeks ago. I got one from the auto parts store and it wasn't the same so I had to go to the dealer to get one for a marine engine. My boat would not run cool with out it. As long as it was at a idle it was fine but once you started to rev it up the temp. wold jump way up. This is due to the thermostat in a marine engine will close allowing more water to run through the engine. If it is not there to close it will go straight out the exhaust.

I may be way off base, but this is the conclusion I came up with. Now if you have a closed cooled engine it would not be a problem. I know people have told me that you can do it, but in my case it wouldn't work out and the automotive t-stat was different then the one that was in my boat. I have the MCX engine and they may make some kind of difference as well. Hopefully someone will come along with more credintals and correct me or back me up on this.