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scottpiper27
08-23-2013, 08:25 PM
Hi All - Thanks in advance for all your help again.

The boat is a 1990 prostar 190 with ford indmar velvet drive trans.

A quick question about temperature. Im the second owner of this boat, the temp sits right at 160 while running, runs good. When I turn the boat off for a few minutes after running it, then start it back up, the temp shoots up and the alarm goes off for few seconds until I put it in gear. Temp is fine at all other times.

I was told to clean out the strainer tube before the intake. I ran some detergent product through it and scrubbed it the best I could, seemed to help a little, but still has the same problem.

I was thinking about going back to a 145 thermostat to help keep things a bit cooler, but alot of people say the 160 is a better temp to run the engine at. My friend has the same boat and runs a 145 and never has this problem, but I don't want to switch if it has a negative effect on engine health.

Any suggestions?

Thanks Again - Scott

j.mccreight@hotmail.com
08-23-2013, 09:03 PM
Hi All - Thanks in advance for all your help again.

The boat is a 1990 prostar 190 with ford indmar velvet drive trans.

A quick question about temperature. Im the second owner of this boat, the temp sits right at 160 while running, runs good. When I turn the boat off for a few minutes after running it, then start it back up, the temp shoots up and the alarm goes off for few seconds until I put it in gear. Temp is fine at all other times.

I was told to clean out the strainer tube before the intake. I ran some detergent product through it and scrubbed it the best I could, seemed to help a little, but still has the same problem.

I was thinking about going back to a 145 thermostat to help keep things a bit cooler, but alot of people say the 160 is a better temp to run the engine at. My friend has the same boat and runs a 145 and never has this problem, but I don't want to switch if it has a negative effect on engine health.

Any suggestions?

Thanks Again - Scott

Have you checked the impeller?

Having a 160* thermostat will allow the engine to run more efficiently than having a 142*. However they are susceptible to some heat soak especially if you run it hard, changing out skiers or just shut it down after a hard cruise, Your options are to install a 142* and the heat loss will linear adjust and not get as high on the gauge, or you can do a "cool down" which simply idle the motor for a bit before shutting down. You are probable starting to have some rust, calcium, mineral build up on the internals. I have a 160* in my boat with the ford 351w, I don't have a problem with high gauge reading on restart.

scottpiper27
08-24-2013, 02:21 AM
Hi James - thanks for the advice, the impeller has been changed since the problem has existed and didn't have an effect. But based on what you are saying with running it hard, it makes sense. It's happening between ski runs. I'll let it idle for a while before shutting down, sounds like a better solution then tearing apart the whole cooling system to find a problem that might not exist.

Thanks again, any further advice is welcome.

Kevin 89MC
08-27-2013, 12:06 PM
Awhile back I switched to a 160 degree when I added a shower, thinking I needed the extra heat for the hot water. I was also planning on adding a heater. I would often get a high temp alarm upon startup after a footing or slalom run. Idling did help some, but alarm would still go off occasionally. I switched back to a 145, shower water is still plenty hot, and I almost never get the alarm (only one time this year after a WOT run and no idle).
Good luck,
Kevin

mikeg205
08-27-2013, 12:41 PM
If you haven't inspected the water channels in the riser and manifolds this late late fall would be a great time. You can start cleaning out your water jacket with - Evaporust www.evaporust.com or metal rescue (Menards) - both non corrosive and safe on gaskets.

The heat soak usually gives you 10-20 degree uptick in temps after shut off depending on the water temp.

I inspect my risers and manifold every season and have been flushing them with evaporust before winterizing... getting almost a new look in the water channels. Gaskets are cheap -

Top photo shows much of the scaled rust removed asa compared to the right. bottom photo show clean channels in riser... The orange in picture 2 is permatex copper gasket RTV - have a few pits - PO never changed gaskets.

riverinstructr44
08-30-2013, 12:21 AM
All very helpful...Thank You