All right I have down a search and looked through everypost that I found. I have a just bought a 1999 Supra Santera. The first day we took it out the boat ran fine and then the gauge showed that it got a little hot and then out of nowhere it dies no power or anything. After about ten minutes of looking at all the connections and fuses we get power back and it ran fine still hot 200ish but fine. I felt that the temp gauge was inaccurate though because I could still easily touch the intake manifold as well as exhaust manifold. Next day, changed the impellar checked the transmission cooler and the water strainer that is right after the thruhaul. Nothing in there. Ran in the boat off of the flush adapter and it ran about 170-180. Took it out and it ran and those temps all day and then towards the end of the day it started running hot again according to the gauge anyway. Checked the engine physically and it was hot but I could still touch it for a few seconds. The gauge was showing like 220-230. I engine never sounded any different or never saw any puffs of steam. My next steps are to do a ground check on the temp gauge and maybe replace the thermostat. If anybody have any other advice to add I would love to hear it. Oh yeah took it out today and it was still running hot according to the gauge. Thanks for the help in advance.
Tighten all your hose clamps you may have a small airleak. When you replace t-stat check for old impeller pieces clogging lines. Make sure the o ring in the strainer is good and it seals. Verify guage...220-230 is way too hot to run it.
Okay I think I might have narrowed this problem down a little bit. I ran a the boat off the hose in the yard and ran a grounding wire directly from the gauge to the negative battery cable and bam let the boat run for a solid 15 minutes and never got above 160 maybe 165. If I disconnect the grounding wire it immediately goes to 180-200ish. With the grounding wire disconnected if I turn anything else on i.e. blower or anchor lights the temp gauge then spikes to 240. So obviously I have a grounding problem with my gauges. Oh yeah when I took it out yesterday it was late so I had the anchor lights on which could be the reason for the higher temps on the lake yesterday.
Jeremiah you hit it on the nose. I had the same problem the other day on the "D" I sucked mud in and the boat started running hot. I shut down and changed the impellar. Then the boat ran about 190 where normally it runs 175 on the spot and never moves. I thought maybe there was mud still stuck in there. Then when I would go over bumps some of the guages acted funny. So I removed the guage panel and nothin. Then I checked the battery and low and behold. A barely loose connection on the negative side. Tightened it up and bam 175 steady and everything was all good. Then we topped it off with a great sunset ride
Yeah I do owe it to BigE. Haven't forgot about the generators yet either. I still have to find out where the ground problem is though. Don't feel like running around the lake with "temperature grounding system" in place.