496HO closed system what is normal water temperature?

[07Southbay925CR]

2003 playcraft tritoon 2700 xtreme
496HO closed cooling
bravo x drive
300 hours

just had impeller changed (housing good)
thermostat changed

I didnt pay close attention to the first couple trips after change. But now I'm running 180 to 185 open throttle. Almost 200 at idle. No temperature alarm goes off. Are these normal temps for a closed system? I'm not sure if I was ever running 160 before the impeller change(new ti boat)

starboard thru hull exhaust has just a small steady stream... when port exhaust is spitting out a lot.

could it be a "flapper" causing this temperature issue? Can you tell if flapper is still in place and functioning be doing something something?

 

[Scott Danforth]

Pull rhe elbow and inspect the flapper

Are you in salt water and have you checked for "bravoitus"?

 

[07Southbay925CR]

I have corsa captains thru hull. Do I need to slide the rubber grommet towards stern drive? Also.... I have a rubber grommet #1....then corsa captains piece... then another runner grommet #2 before it runs through hull. Which grommet do I need to move and which way. #1 or #2.

What would be the best temperature gun to run and get at an auto parts store. I want to double check my temp guage. What should it read pointed at where the temp sending unit is? Is this the temp of my closed unit antifreeze?.... where else should I check for raw water temp? Manifolds, risers?

two temps?
exhaust raw water
engine closed antifreeze

could I possibly have two issues? One with my closed system and one with my raw water for exhaust? Just wondering what drives the temperature guage on my helm.

below was my temp running for about 30 minutes. It stayed constant there.... but would jump to a about 195 if I went to an idle.... then back down to 180ish+ half throttle.

 

[07Southbay925CR]

This is my starboard exhaust that is just peeing a steady stream of water. Which grommet would I need to slide and which way

 

[07Southbay925CR]

Oh, never in salt water.
not sure what bravoitus is?

 

[tpenfield]

Was the impeller changed because it failed? If so, there could be the remains of the impeller caught at the oil cooler.

The temperatures that you stated are too hot. I’d back-flush the water intake system first (heat exchanger inlet to the sea water pump outlet) and see if that provides any remedy.

 

[07Southbay925CR]

Timeline:
bought boat September 2017.
ran boat handful of times.
honestly didnt pay close attention to temp guage
but I know it was in 160 to 180 range
had it winterized
shop told me I'd need sea water pump or impeller next year
I'm pretty certain they guage it by starboard exhaust not pumping out enough water.
spring 2018, pump housing fine, replaced impeller and thermostat- same.shop
and of course... not paying close attention...3rd trip out... someone stops me on water and says my port exhaust is pumping alot more than my starboard
I start watching the temp guage religiously
it stays a hair above 180 running normal throttle
it jumps to shy under 200 at idle

Can somebody explain a "half closed cooling system"
is the temp guage on my helm showing my block temp?
my heat exchanger, manifolds, risers are on raw water correct? I'm not seeing the temp of those on the helm temp guage correct?

 

[07Southbay925CR]

And how do I back flush?

 

[tpenfield]

A 'half' closed cooling system cools just the engine block with the closed system the exhaust manifolds and elbows are cooled with raw water.

A 'full' closed cooling system cools both the engine block and the exhaust manifolds with the closed system. The elbows are still cooled with raw water. Obviously, a full system needs a bigger heat exchanger since the closed side of the system is cooling more of the engine.

The temperature gauge at the helm will show the engine block temperature, and nothing else.

To backflush . . With a closed cooling system you can disconnect the raw water input hose at the heat exchanger and the hose on the outlet side of the sea water pump. Then force lots of water down the hose that you disconnected from heat exchanger, which essentially reverses the normal flow of water leading from the sea water pump to the heat exchanger. This should dislodge and clear out anything that is stuck in the 2 inline coolers that are between the sea water pump and the heat exchanger.

 

[07Southbay925CR]

Update.

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 guage showd 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.

just to check myself...

Is thermostat on port side below the heat exchanger? (Long cylinder deal)?

raw water supply coming in from port side underneath? (Read outside temp here)

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.

the "squashed" chamber that runs with length of heat exchanger cylinder???.... it was 154 the length of it.

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?

port manifold was 114. Starboard was 109.

what do ya think?
I was told that being a half gallon low shouldn't have given me the symptoms of 182 running 195 idling.

I'm getting ready to test in water.

 

[07Southbay925CR]

Water test.

temp guage on helm was 180 while running.... infrared gun showed 164.

temp guage on helm 190 while idling... infrared gun showed 170.

water temp is probably 83 degrees..... so I guess I have to take that into.account for the temp difference than on water hose?

would you still be concerned at 170? Plus that was on one of those 30 dollar ones ar autozone... think that's accurate? I was measuring right at the thermostat. Where would the temp guage on helm ne measuring at? Should I check into more things since the helm temp guage is so high?

 

[alldodge]

temp guage on helm was 180 while running.... infrared gun showed 164.

temp guage on helm 190 while idling... infrared gun showed 170.

water temp is probably 83 degrees..... so I guess I have to take that into.account for the temp difference than on water hose?

The starboard side exhaust is always hotter then the port, is because water flows the path of least resistance and its a bit easy to that side.

Assuming that your measuring your temps at the thermostat housing then your gauges are off a bit, so I would say your good to go and have fun.

Your manifold temps are great