11-26-2017 08:59 PM
If your temp setup is the same as mine, the sender is in the coolant side of the coolong system, not the raw water. It's on the front right hand side of the motor at the topjust in behind the front engine guard. The sender is a floating earth type with 2 wires. I had a guage guy in last week and he will be back this week to fit a couple of in-line variable resistors, so we can adjust the guages to read right. We intend to fit the resistors and run the engines up to operating and check the temps with an infared heat gun, then adjust the resistance to correct the guages.
11-24-2017 08:26 PM
Provided you have the correct part number indicators and senders ( 12V or 24V ) these are insulated (above earth) 2 wire systems. If you have any resistance from the earth return wire at senders to battery negative then this will result in an indicator reading offset.
11-12-2017 10:31 PM
After months of diagnostics and checks we found that the gauges are way out. We tried more new senders and gauges, every time we put another set in we got a different reading. All guages were the VDO units from Cat with matching Cat senders....these electronic gauge sets are absolute crap; they read up to 15C or 59F out (high). In the end we got the local Cat dealer to hook the motors up to their diagnostic gear and recorded 190 degrees at 2200 RPM for both motors. At idle 189 degrees and at WOT (2800) 192 degrees steady.
No body seems to be able to tell me why the gauges are so inaccurate but I'm seriously pissed off with Cat. I dont know if the gauges can be re-calibrated in the boat or not. Next step is to take the Cat gauges and senders out and deep six them for the rubbish they are. A set of Murphy mechanical gauges should fix the problem and I can go boating in confidence.
07-09-2017 07:45 AM
I am having the same issue right now on the same engines on a 1991 Princess. I had the after coolers cleaned out last year and was doing better. But this year I am back with climbing temps. I am going to pull the trans coolers next and flush them out to see. I am still trying to find out is the temp gauge reading from the closed loop side of the cooling system or the open loop side. I need to dive into it a little more but have been busy. Hoping next week to get in the engine room and see what happens.
07-07-2017 02:09 AM
I have a 45' Caribbean (Bertram) with 2 x 3208 TA's 435 hp engines - serials 01Z33399 and 01Z33400. When I bought the boat about 18 months ago the Port engine ran about 206 degrees and the Starboard on around 210 at 2200 rpm. When I increased the revs, the temps gradually increased.
Since then I have been given all kinds of conflicting info on what is the right temp; including conflicting info fro 2 fitters at our local Cat dealer Westrac. Some say 210 is too high and some say it's ok. The thermostats are 190 degree openers.
I have pulled off all raw water coolers, heat exchange, aftercooler and transmission coolers and had them cleaned out. I have relaced all hoses and put in brand new raw water pumps. I have taken off the shower heads and cleaned them. All of the cooling components had some scaling but not much. No change to temperatures, so I relaced the gauges and sender units - no change.
I checked the temp alongside the senders and came back with a reading of 197 degrees for both engines. I plugged in a mechanical Murphy gauge into the sender hole and that came in at 200 degrees - all at 2200 rpm.
I'm getting a little cheesed off - does anyone know what the temp should be and if too high, what else might be the issue. The engines have done around 760 hrs.