225 pro xs possible thermostat issue

[Shaun96]

Hey guys this is my first post. I have a 2014 225 pro xs and I believe I’m having some possible t- stat issues. I bought this boat from a reputable dealer and the first time I take boat out on water I get a 4 beep alarm at idle. I noticed a drop in water pressure and my operating temp on smart craft gauge was running low like 78 deg. So I idled back to the ramp. About 10 min after idling back the water pressure built back up and the temp went back up to operating temps. Took boat back to dealer they said there was debris in port side t- stat. All good to go. I get boat back take it out and I make three runs and on my next one when I started boat same thing. Water pressure dropped and temp. So I idled back to ramp. Once again after a long idle water pressure went up as well as temps. I thinking t stat is stuck open and then it finally closed. I take the boat back again to dealer. They said they pulled both t stats and flushed system and put me t sats in. I don’t think they did as the only wrench marks on bolts are on port side. I know that smart craft gauge only reads port side temp or so I believe that’s correct. The starboard side had no wrench marks at all. So I once again get boat back. Still this time no wrench marks on starboard side t stats. Which believes me that it’s never been pulled out. So I take the boat out. It does fine all day until I go to load boat up. I dock and turn off engine. Go get trailer and fire boat back up. I notice water pressure is running low and temp falls to 78. 5 min later pressure back up and temp to normal. So I get home and I pull both t stats. They are both clean of debris. I can tell that the starboard side has not been replaced. So after I put all back together I run boat on muffs operates as it should. I ran it for prob 5-10 min. I turned it off and let it sit for 5 min. When I turned it back on the temp and water pressure fell. 5 min of idling water pressure went back to normal and temp went to operating temp with stats opening and closing as should. So what I’m seeing is naturally after running motor and turning off heat soak happens. If the motor is above 130 deg and I start it the t stat seems to be stuck open. If it’s lower like 128 deg and I start it it operates as it should. So I’m thinking that the starboard t stat is weak. Should I be looking at something else
serial number 2B115396

[BlazerVA]

I have been through the same thing numerous times. You probably have debris in your cooling system. Pull the strainer (port side)and both thermostats. Hook the hose up to it and flush it out for a few minutes. Throw the stats in a pot with water on the stove and check what temp they open at. Should be 130 I think. The smallest of trash can cause the tstats not to close all the way. Check the poppet valve also. If its sticking open it'll cause it to not heat up. I fish shallow grassy rivers here. 2ft is about the norm for me. I carry a tool kit and pull them on the water when it happens. Once you do it a couple times its easy. You def dont wanna run it cold.

[apdriver]

I had some weird cooling issues. Engine not coming up to temp. Replaced the thermostats and still had issues. Replaced the poppet and it fixed it.

[Savage]

Smartcraft gauge displays the average temperature between BOTH (2) cylinder head temperature sensors.

[Shaun96]

I have not ran it above idle when this has happened. Don’t want to risk damaging. Could it be the poppet valve? I start the motor and temps build just as they should and t stats open then close and work as they should. After I shut engine off and go back to start up if the engine temp at that time is above 130 it happens. Water pressure will drop and temps drop to 78. Water temp is 60-61 deg where I am at the moment. If the engine temp is below 130 I start it up and water pressure is good and t stats open and close. But when it does do it, 5 mins or less is what it takes for it to start working properly.

[Shaun96]

Smartcraft gauge displays the average temperature between BOTH (2) cylinder head temperature sensors.

Ok thank you for that info. I was told it only did port side.

[Shaun96]

I had some weird cooling issues. Engine not coming up to temp. Replaced the thermostats and still had issues. Replaced the poppet and it fixed it.

I guess I’m going to replace the starboard side t stat and go from there. I say that one as I’m pretty positive only the port side got replaced. If that isn’t it the poppet next.

[EuropeanAM]

If you would, please take a moment to review the Announcements at the top of the Forum, and be sure to provide the Required Info (serial number) when posting. Thanks!

1. Clean strainer and back flush engine while strainer is out.

2. Remove and test BOTH thermostats. Must be suspended in water on a STRING. Remember- it's not just "do they open"... you need to make sure they close quickly if moved to COLD (room temp) water.

3. If problem persists, check poppet valve (replace grommet, gaskets, spring, poppet and diaphragm). MUST move in and out of seat as if buttered (zero effort to move poppet in and out of grommet/seat).

[Shaun96]

So quick update. I put new t stat in on starboard side as I suspect it didn’t get replaced at dealer even though they told me it should have been. Also I was charged nothing for the work they done I just don’t think they were through as they said. So I put new stat in and I don’t have the issue anymore of the temp dropping down to 78 after the engine has heated up been shut off and then restarted. Now I restart and temp falls a little down to 107 and begins to climb back up to 120. It will run at 118 on the muffs steady. Not rising or falling just holding that temp. Before switching the starboard t stat it would rise and fall between 130s and 118.

[Bob G.]

Should run at or above 120 on the muffs with 130 degree thermostats. I would test both thermostats and clean strainer/flush motor as Don suggested.

[Shaun96]

Should run at or above 120 on the muffs with 130 degree thermostats. I would test both thermostats and clean strainer/flush motor as Don suggested.

That’s what I was thinking. But what seems odd to me is that the port side stat was already replaced by dealer. I was still having issue as I stated in original post. I was suspecting a weak spring in the starboard side stat as it wasn’t replaced. After I replaced starboard side I don’t have the issue of falling temps after heat soak. But I’m only getting 116-118 on idle on muffs. Once temp rises and stat opens and it settles on 118 for several min then 116 for 15 plus min at idle without fluctuations at all. I will have to research on how to clean strainer.
Thanks

[Bob G.]

http://www.bbcboards.net/showthread.php?t=565408

[Shaun96]

If you would, please take a moment to review the Announcements at the top of the Forum, and be sure to provide the Required Info (serial number) when posting. Thanks!

1. Clean strainer and back flush engine while strainer is out.

2. Remove and test BOTH thermostats. Must be suspended in water on a STRING. Remember- it's not just "do they open"... you need to make sure they close quickly if moved to COLD (room temp) water.

3. If problem persists, check poppet valve (replace grommet, gaskets, spring, poppet and diaphragm). MUST move in and out of seat as if buttered (zero effort to move poppet in and out of grommet/seat).

Thank you for the info. I’m struggling trying to understand after I changed the starboard side t stat that it dosent drop to low temps as it did before after heat soak. But now it seems the t stat opens before 130 and drops to 118-116 and stays at those temps

[EuropeanAM]

It is possible to have temps such as those and still have a thermostat that is stuck open (or doesn't close properly).

[Shaun96]

Pulled both t stats out again. Checked them for working properly. Both opened and then when put in room temp water closed fast. Nothing at all in them as far as debris. Put them back in and temp gets to 118 on smart craft gauge and stays steady. Before I put new t stats in it would run warmer.

[EuropeanAM]

Check the thermostats carefully to make sure the valve portion is centered in the outer body. This can be the difference between "closing" and "sealing".

In some cases, you may need to see if you can blow air through the thermostat to confirm it's sealing properly (had one recently that was not properly centered, there was an abnormality in the body of the thermostat, which forced the valve to sit off-center).

[Shaun96]

So I took the boat out on the lake today for a few hrs. Everything worked perfect on the water. Temps ran in the low 120s at idle and my issue is fixed. The culprit was a slow closing starboard t stat.