03playcraft496HO;n10597052 said:
but I know it was in 160 to 180 range
That's where you want the temp to be.
replaced impeller and thermostat.
If the engine continues to run normal temps after adding coolant, then chances are you had some air in the coolant system along with being that much low. This system needs to be right on or the engine will run warmer like you were seeing....There's a air bleeding procedure they may have not done 100% correctly after replacing the thermostat which sits under the big round cylinder tube being the heat exchanger.
Someone stops me on water and says my port exhaust is pumping alot more than my starboard
That usually tends to be a water flow restriction issue on the raw water side but then again this design engine has done many ghostly phenomenon's in the past and being low on coolant sounds familiar for odd water flow situations like that....I wouldn't be to surprised if that was the overall issue after an thermostat change on this engine.
I start watching the temp guage religiously
it stays a hair above 180 running normal throttle
it jumps to shy under 200 at idle
Generally with average lake water temps the engine temp shouldn't be much over 179...Maybe 181 on pretty warm lake waters on the gauge side of the system.....The ECM sending unit is usually much more accurate and reads a lower temp vs the gauge when connected to a MPI scan tool device. Usually the scan tool will show about what you were reading with the infrared temperature gun you mentioned this morning vs the gauge.
Is the temp guage on my helm showing my block temp?
Yes pretty much though the senders are on the crossover tube you just mentioned this morning.
Sensor item number 8 is your gauge temp while sensor 7 is the ECM and Warning Horn for temp....#1 is the crossover tube,
http://www.marineengine.com/parts/m...w309999/cooling-system-fresh-water-components
My heat exchanger, manifolds, risers are on raw water correct? I'm not seeing the temp of those on the helm temp gauge correct?
Correct.....
http://www.marineengine.com/parts/m...687083-thru-0w059999/raw-water-cooling-system
If I remove those ends of the heat exchanger... is there anything to be careful about? Do I need to flush and how so. Will I need to watch for air getting in?
It's generally best to try and order and install new gaskets and bolt seals after each inspection as soon as you can... Part numbers, 25-814878 - O RING, 27-891716 - Gasket -
It's also recommended to use something such as Mercruiser's Quicksilver Perfect Seal or Permatex Aviation Form a Gasket from an auto store and torque bolts to 54-lb-in.
There are bunch of honey comes holes that run down the center of the heat exchanger and they tend to get plugged up with debris at times so its a good idea to inspect them every once in awhile anyways especially if you run in debris type waters like sand, etc. etc.. You shouldn't find any coolant inside the center of the HE, only lake water.....No air issues to be concerned with by removing the center caps too.
Also, when I turn my key to start position, I hear the audible beep... assuming that is testing the alarm? Is the alarm set to the gauge on the helm or to the ecm on the motor? Could there be a problem with the alarm even though its sounding at start?
While the alarm horn is mounted up under the helm area, it's not part of the actual temp gauge per say....The horn is separated from the gauges and activated by the ECM in this case....The audible beep you hear is a self test system telling you the horn system is working correctly at key up which is good to know since you never heard the horn telling you the engine never truly got to 196+ degrees.
The horn should look like this,
https://www.ebay.com/itm/OEM-Factor...6-816492A15-/400635922125?hash=item5d47c306cd
Again air in the coolant system will make the gauge read hotter too on that side of the crossover tube.
So in the dark this morning I checked the coolant level. It took half gallon. I started it up on water hose. It ran 164 at the thermostat with a infrared gun. Helm gauge showed probably 170. I ran it a good 30 mins with captain call on and off if that matters and raising lowering outdrive. And guess what else... its spitting out both tail pipes like normal now.*
Hope it does all that on the water too...Good luck.
just to check myself...
Is thermostat on port side below the heat exchanger? (Long cylinder deal)?
Yes in the crossover tube item number 9,
http://www.marineengine.com/parts/m...w309999/cooling-system-fresh-water-components
raw water supply coming in from port side underneath? (Read outside temp here)
After the water flow leaves the impeller housing on the starboard side of the boat/now your left facing the engine inside the boat...The water flows over to the port side of boat/your right side and up into a majority of the engine accessory components....
http://www.marineengine.com/parts/m...687083-thru-0w059999/raw-water-cooling-system
Is the long cylinder the heat exchanger? It was 88 on ends... *155 where thermostat comes in.... 135 in middle of cylinder. So it was hottest where thermostat goes in...then decreases to starboard side.
Yes it is and that all sounds about right temp wise for normal...Hope it stays there for you now.
the "squashed" chamber that runs with length of heat exchanger cylinder???.... it was 154 the length of it....
Though not important enough for a reply back at this point, Not to sure here...Items that can be considered squashed down would be the pad item number 16 or the 2 seals that hopefully they put 2 news ones in are # 14,
http://www.marineengine.com/parts/m.../0m687083-thru-0w059999/closed-cooling-system
Port manifold was 114. Starboard was 109.*
Sound good enough...Hope it all stayed the same while out on the water for you....Keep close eyes on everything/every trip with your temp gun handy.
I was told that being a half gallon low shouldn't have given me the symptoms of 182 running 195 idling.*
Yes it could plus most likely having air in the system would do it too.
The hose coming out of starboard side of heat exchanger/squashed part... was 135 circling back into engine. Is this small hose cooling the block?
If you can see the following screenshot image, here's the engine water flow for your 496 engine... A = sea water flow and B = Coolant flow.