CAT 3126s overheating/running hot after sucking up mud

I am flushing the starboard engine aftercooler today, took a shortcut since I knew I was going to replace one of the hoses anyway. The initial water coming out was dark brown

 
mrsrobinson said:
I am flushing the starboard engine aftercooler today, took a shortcut since I knew I was going to replace one of the hoses anyway. The initial water coming out was dark brown

Click to expand...

I'm pretty sure that the pump you bought does the job. For my flushing, I looked at a bunch of pumps and settled on the Drummond 1/4 hp 3000 gph from Harbor Freight, $70. Thought process was to keep it in the engine room for an emergency after that. Have a bunch of rollup 2 inch discharge hose and a piece of rigid pvc for the overboard discharge. Hopefully it will never see action!
 
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mrsrobinson said:
Four and a half hour flush of the starboard aftercooler in both directions, warm up for 15 minutes at the dock, weather not favorable for a sea trial. I still think the starboard engine is running too warm

https://photos.app.goo.gl/ExMV6TWx9PuXRDbs9
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those temps seem fine to me but it is odd they’re so different if they were running the same amount of time. No load does nothing though, it’s not really burning much fuel

what temp is hose dumping into the riser on the port side? I think I saw your starboard one was like 85* so that doesn’t seem to be pulling much heat out of the raw water is 75-80* coming into the boat
 
I put the gun on the hoses coming into the boat, temps were 82. See one minute 30 seconds into the video. Port engine at the thermostat and expansion tank is 25 to 30° cooler then the same spots on the starboard engine. The port engine is the engine running cooler at load now as well.

I found it interesting the water on the port fuel cooler hose was about six or seven degrees warmer than the strainer hose. Maybe that's the difference between shooting the temp on rubber versus metal?

If I follow your train of thought you are saying if the raw water coming into the boat is mid-80s then the raw water exiting the boat should be in the mid to upper 90s showing heat exchangers/coolers are doing their job correctly?
 
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Sgrochow said:
I'm pretty sure that the pump you bought does the job. For my flushing, I looked at a bunch of pumps and settled on the Drummond 1/4 hp 3000 gph from Harbor Freight, $70. Thought process was to keep it in the engine room for an emergency after that. Have a bunch of rollup 2 inch discharge hose and a section of rigid PVC for pickup. Hopefully it will never see action!
Click to expand...
Yup, when I did my research 5 to 6 gallons per minute seemed to be the norm. The one I used was 800 gallons per hour. I don't think it's so much the pressure of the water flow as it is the soaking and movement. I could be wrong though.

All of the broken off zincs were gone, which is something I wanted. I replaced all five on each after cooler after the flush. I had to soak two of the bolt heads to remove the remaining zinc inside of them.
 
mrsrobinson said:
I put the gun on the hoses coming into the boat, temps were 82. See one minute 30 seconds into the video. Port engine at the thermostat and expansion tank is 25 to 30° cooler then the same spots on the starboard engine. The port engine is the engine running cooler at load now as well.

I found it interesting the water on the port fuel cooler hose was about six or seven degrees warmer than the strainer hose. Maybe that's the difference between shooting the temp on rubber versus metal?

If I follow your train of thought you are saying if the raw water coming into the boat is mid-80s then the raw water exiting the boat should be in the mid to upper 90s showing heat exchangers/coolers are doing their job correctly?
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correct, but I’m really reaching there. I have no idea what it should be, and the cooling system is so overbuilt maybe there just isn’t that much heat to be removed when running with no load.

that temp just caught my eye but it could be completely normal. Did you do the flow test on both sides to see if the proper volumes are being ran through the raw water side?
 
I have not done any flow tests, the service shop owner did leave me a 12-in x 2-in piece of clear tube when I'm ready.
 
mrsrobinson said:
Yup, when I did my research 5 to 6 gallons per minute seemed to be the norm. The one I used was 800 gallons per hour. I don't think it's so much the pressure of the water flow as it is the soaking and movement. I could be wrong though.

All of the broken off zincs were gone, which is something I wanted. I replaced all five on each after cooler after the flush. I had to soak two of the bolt heads to remove the remaining zinc inside of them.
Click to expand...

Agreed, when I bought the pump was trying to figure out some way to perhaps put it to use in the future, however unlikely that may be.
 
Look what I found today starboard engine which is the one still running hot

https://photos.app.goo.gl/Am76uVoXdqL5WjeY7

PXL_20220827_141452905.jpg
 
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Maybe A Dancer said:
=====================================

If we establish a pool and take bets on this, I'd be putting my chips on the HEX and the aftercooler

RWS
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==================================================

What did I win ?

RWS
 
Cleaned her up, barnacle buster flushed it for 4 hours, took her for a sea trial ran at 180. What's confusing to me is where did those come from, the raw water impeller I pulled did not have any broken fins.

That's why I didn't pull the cap off on that side, because the raw water impeller looked pretty good. Now I wish I would had done it, I had to remove the exhaust and everything today to get to it. Replaced some raw water hoses while I was at it.

Port engine still running just under 200. Boat lost some speed, because it's been sitting for three and a half months, I got some growth on the bottom.
 
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mrsrobinson said:
Cleaned her up, barnacle buster flushed it for 4 hours, took her for a sea trial ran at 180. What's confusing to me is where did those come from, the raw water impeller I pulled did not have any broken fins.

That's why I didn't pull the cap off on that side, because the raw water impeller looked pretty good. Now I wish I would had done it, I had to remove the exhaust and everything today to get to it. Replace some raw water hoses while I was at it.

Ford engine still running just under 200. Boat lost some speed, because it's been sitting for three and a half months, I got some growth on the bottom.
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Probably from multiple failed impellers over the years.

the why part will probably always be a mystery. Who knows, maybe they somehow got pushed upstream when you jammed the mud in, or higher pressure from restricted flow crammed them into the tubes enough to restrict flow

have you pulled the cap on the other side to this extent?
 
mrsrobinson said:
Cleaned her up, barnacle buster flushed it for 4 hours, took her for a sea trial ran at 180. What's confusing to me is where did those come from, the raw water impeller I pulled did not have any broken fins.
Click to expand...
I had the same thing - no lost blades when I changed mine the first time, but more for curiosity, I took the end caps off and they were jammed with impeller blades from previous changes. FW told me that CAT overengineers their cooling systems, and I never had any temp indications of clogged HEs though...
 
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