LT-1 still runs cold

[1redTA]

gauge should be on the water pump the ECM should be in the head (car)

[Jerseydave]

Originally Posted by Stx221

The temp sensor that the arrow points to is for the ECM. There is another sensor somewhere for the gauge, but I don't know where it is located based on memory. As far as I know, the ECM and the gauge do NOT get a reading from the same sensor.

I can find the location of the other temp sensor for you this weekend when I have access to my repair manual. I wonder if the sensor for the gauge is off slightly, but the ECM is seeing the correct temps? Does the boat run well?

For what its worth, mine runs at approx 140 degrees all day every day...

Correct, the sensor with the arrow in pic above is for the ECM. 2 wires, yellow and black.
The sensor I replaced is for the guage for sure. It does seem to me that sensor will always read a colder temp than the ECM sensor. Not sure why they chose to have those sensors where they are because they will never read the same water temp IMO.
The boat runs perfect. I will take a infrared temp gun out with me next time to check various engine temps in various locations on the engine.

Maybe some other LT-1 owners can see if their guage sensor is in the same spot, and post what your engine temp is when running the boat. Stx221, nice to know you're running 140 all the time....sounds about right for guage reading. I bet the actual engine temp is closer to 160 because of the top t-stat. Perfect temp.

[langedp]

Posted a reply awhile back in your other thread in the electrical section. My '94 LT1 has the ECM sensor in the same place as yours but my temp gauge sensor is on port side engine head. My engine temp reads around 140 unless I run hard for awhile then it climbs up to 160 and levels off.

[Jerseydave]

Originally Posted by langedp

Posted a reply awhile back in your other thread in the electrical section. My '94 LT1 has the ECM sensor in the same place as yours but my temp gauge sensor is on port side engine head. My engine temp reads around 140 unless I run hard for awhile then it climbs up to 160 and levels off.

Thanks, I'll take a look tomorrow for it on the port side head.
If you have a pic of it that would be nice too.

So do you also have a temp sensor in the mixer like mine, or nothing there?

[langedp]

There's nothing in the mixer. Here's a pic of the head with the sensor removed. I don't have one handy that shows it in place and the boat is up North. There's also a pic of the sensor itself. Not sure if this is a standard location either.

Dave

[langedp]

Here's one of the engine. The sensor wire is laying on the carpet as I was trying to figure out my temp problems.

[pram]

Originally Posted by Jerseydave

Maybe some other LT-1 owners can see if their guage sensor is in the same spot, and post what your engine temp is when running the boat. Stx221, nice to know you're running 140 all the time....sounds about right for guage reading. I bet the actual engine temp is closer to 160 because of the top t-stat. Perfect temp.

Originally Posted by langedp

Posted a reply awhile back in your other thread in the electrical section. My '94 LT1 has the ECM sensor in the same place as yours but my temp gauge sensor is on port side engine head. My engine temp reads around 140 unless I run hard for awhile then it climbs up to 160 and levels off.

So I am not the only one who's gauge only reads 140 then. I would have thought that it would be at 160?

I have an infrared gun that I am going to try it tomorrow

[formosa]

Mine is normally 140 ... 160 after running hard as well.

[langedp]

Originally Posted by pram

So I am not the only one who's gauge only reads 140 then. I would have thought that it would be at 160?

I have an infrared gun that I am going to try it tomorrow

Now that the lake temp is warming up, the engine seems to get up to 160 faster. It holds there pretty well so things seem to have stabilized.

[Jerseydave]

Originally Posted by langedp

There's nothing in the mixer. Here's a pic of the head with the sensor removed. I don't have one handy that shows it in place and the boat is up North. There's also a pic of the sensor itself. Not sure if this is a standard location either.

Dave

I just have a pipe plug in my left-side cylinder head. It makes perfect sense to have the gauge temp sensor there and not in the mixer.

I have not had the boat out for a few weeks so I did not get a chance to test the actual engine temp with an infrared temp gun.