Well guys, back to the drawing board :-(
Swapped back in the old thermostat that works properly and while it idled at 170? (like the starboard engine) as soon as I increased the RPM it started overheating again. I removed the thermostat completely so I could go out and enjoy memorial day (only took it about 2 miles from the marina). During the trip the temperatures quickly climbed to over 210?, so I stopped and decided to remove the thermostat completely, since that worked when I was trying to determine if it was bad. After this it dropped to about 170?, then bounced around a lot, everything from 100? to 170? (not overheating). I thought that everything was going to be okay, but I realized I couldn't get over about 2400RPM, any higher and it would misfire, have preignition or some other symptom that caused the RPMs to instantly drop about 200 ever time I tried pushing it. Most of the time I had to keep it around 2200RPM. sometimes when it happened it would sound like a loud pop was coming from the engine bay, but not every time
New suspicion:
Could this be the TPS? In other words, could the engine think that I'm at idle throttle and be giving it the idle throttle amount of air even when I raise the RPM (by increasing fuel)? This wouldn't cause overheating would it? Could the TPS also cause the timing to be off, causing preignition?
I'm about ready to take it to a mechanic to have it positively identified, but I would really like to figure this out myself... I really wish the thing had OBDII :-/
Swapped back in the old thermostat that works properly and while it idled at 170? (like the starboard engine) as soon as I increased the RPM it started overheating again. I removed the thermostat completely so I could go out and enjoy memorial day (only took it about 2 miles from the marina). During the trip the temperatures quickly climbed to over 210?, so I stopped and decided to remove the thermostat completely, since that worked when I was trying to determine if it was bad. After this it dropped to about 170?, then bounced around a lot, everything from 100? to 170? (not overheating). I thought that everything was going to be okay, but I realized I couldn't get over about 2400RPM, any higher and it would misfire, have preignition or some other symptom that caused the RPMs to instantly drop about 200 ever time I tried pushing it. Most of the time I had to keep it around 2200RPM. sometimes when it happened it would sound like a loud pop was coming from the engine bay, but not every time
New suspicion:
Could this be the TPS? In other words, could the engine think that I'm at idle throttle and be giving it the idle throttle amount of air even when I raise the RPM (by increasing fuel)? This wouldn't cause overheating would it? Could the TPS also cause the timing to be off, causing preignition?
I'm about ready to take it to a mechanic to have it positively identified, but I would really like to figure this out myself... I really wish the thing had OBDII :-/