Map sensor? Motor boggs at 2100 rpms

[tommcat]

Originally Posted by bartman

I looked at the manual I found online for the PS190 and I thought it said normal temp was between 170 and 195. Normal Oil Pressure at idle is between 7 and 30 PSI. In fact, the MC Dealer discouraged replacing the thermostats. Maybe I will replace and see if that helps.

Interestingly, after running at 180 for a while, when you stop, or especially shut off, the temp goes above 180 (but I don't think it goes above 195). It seems like that may be when it starts... I have it scheduled for Monday at the shop to have them put it on the computer to see what exactly the engine is doing and saying. I am thinking that I should do this anyway, since the boat is new to me, to see if I can get this resolved, and to see if there are any other problems looming out there.

engine temp creeping up when you shut it off is normal, that is heat soak.
good call getting it to the dealer, let us know what they find.

[ahhudgins]

Originally Posted by tommcat

engine temp creeping up when you shut it off is normal, that is heat soak.
good call getting it to the dealer, let us know what they find.

I knew it was normal, but I had never paid any attention to how high the temperature got when I shut the engine down with the 142 degree stat. When I used the 160 degree stat and had the problem restarting, I noticed that the temperature had gotten up to 175. I guess at about 30 degrees above normal operating temperature it won't allow it to restart.

[bartman]

Update... The boat is at Flash Marina and they have recreated the problem, run it on the computer and they have no new information for me except that they are calling for technical support :-( Hoping to hear more today so that I can spend some time on the water before the snow flies!

[Jorski]

Normal operating temp for the LT1 is 160 degrees. (same as the temp rating as the top t-stat)

If you are normally running 20 degrees warmer than your thermostat....you have a cooling system problem.

Check, raw water pump flow, look for leaks from the circulation pump, and make sure that you have the correct t-stats and that they are installed correctly and are operating correctly...search for blockages in the cooling passages.

Note the top t-stat needs to be a 160 degree one, with a by-pass hole drilled in it. Make sure to get the mastercraft one...there are many automotive ones that won't work.

[bartman]

Originally Posted by Jorski

Normal operating temp for the LT1 is 160 degrees.

If you are normally running 20 degrees warmer than your thermostat....you have a cooling system problem.

Check, raw water pump flow, look for leaks from the circulation pump...search for blockages in the cooling passages.

Interesting, Thanks! The shop didn't seem concerned about the temp at 180, maybe they missed that it was an LT-1 when we were talking. I am heading up there in a bit to talk to them. I will talk to them about this.

[bartman]

Originally Posted by Jorski

Normal operating temp for the LT1 is 160 degrees. (same as the temp rating as the top t-stat)

If you are normally running 20 degrees warmer than your thermostat....you have a cooling system problem.

Check, raw water pump flow, look for leaks from the circulation pump, and make sure that you have the correct t-stats and that they are installed correctly and are operating correctly...search for blockages in the cooling passages.

Note the top t-stat needs to be a 160 degree one, with a by-pass hole drilled in it. Make sure to get the mastercraft one...there are many automotive ones that won't work.

Jorski - you nailed it. Turns out whoever replaced the 160 thermostat replaced it with a 180. Trying to track one down before this weekend so that I can get out there and see if that really solves it.

Thanks!

[bartman]

Thought I would put some closure to this for my problem, since we never heard back from Sammy! 95 Prostar with LT-1. After eliminating fuel problems, The folks at Flash Marina ran it on the computer, checked all codes, found lots of fun stuff relating to running way to hot. They cleaned out old impeller bits (previous owner replaced the impeller, but didn't wonder where the parts went), checked for other obstructions, and looked at the thermostats. The previous owners installed an automotive 180 degree thermostat in the upper. So the boat was running at 180 and heat soaking above that.

I REALLY wanted to put the right thermostat in and test the boat this weekend, so up to CT for the closest thermostat available (apparently I could have bought an automotive and drilled it, but I wanted to do this right). Installed the thermostat today and spent a little over an hour tolling around Lake Hopatcong, starting, stopping, idling, shutting down and restarting, etc. Temp statyed aroudn 160 - 165 with a bit of heat soak, but nothing alarming. Boat ran GREAT!!! Very excited to put this behind me, and that I have learned ALOT about this boat and basic repair and troubleshooting!

Thanks to all who provided insight and ideas - Much appreciated! See you on the water!

[tommcat]

glad to see you're back in business

[Jorski]

Congrats...now you can get back to having fun!

[Jerseydave]

Originally Posted by bartman

Thought I would put some closure to this for my problem, since we never heard back from Sammy! 95 Prostar with LT-1. After eliminating fuel problems, The folks at Flash Marina ran it on the computer, checked all codes, found lots of fun stuff relating to running way to hot. They cleaned out old impeller bits (previous owner replaced the impeller, but didn't wonder where the parts went), checked for other obstructions, and looked at the thermostats. The previous owners installed an automotive 180 degree thermostat in the upper. So the boat was running at 180 and heat soaking above that.

I REALLY wanted to put the right thermostat in and test the boat this weekend, so up to CT for the closest thermostat available (apparently I could have bought an automotive and drilled it, but I wanted to do this right). Installed the thermostat today and spent a little over an hour tolling around Lake Hopatcong, starting, stopping, idling, shutting down and restarting, etc. Temp statyed aroudn 160 - 165 with a bit of heat soak, but nothing alarming. Boat ran GREAT!!! Very excited to put this behind me, and that I have learned ALOT about this boat and basic repair and troubleshooting!

Thanks to all who provided insight and ideas - Much appreciated! See you on the water!

Glad to hear you got it repaired! Get out there and take advantage of less boat traffic! BTW, we run the Delaware river down here in Florence. You're always welcome to a pull if you wakeboard!