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Engine over heat after tow rope caught

Jmpicking

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It seems like I have restricted flow through the hoses along the path of the pictures attached. The top drain hole above the jet pump is putting out minimal water compared to the other engine. The hose connecting to that port also is overheating at 127 degrees f compared to 107 degrees on the other engine. Any thoughts?
 

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swatski

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It seems like I have restricted flow through the hoses along the path of the pictures attached. The top drain hole above the jet pump is putting out minimal water compared to the other engine. The hose connecting to that port also is overheating at 127 degrees f compared to 107 degrees on the other engine. Any thoughts?
Sounds like you are making progress!

And narrowing it down to an obstruction in a cooling line, somewhere. Assuming it’s not a leak.

Can you identify candidate spots/hoses/junctions and systematically inspect for potential flow issues?

 

Jmpicking

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So I just disconnect the hose one both engines that I suspect being the issue. And then shot water from the inner hose towards to back drain hose. it Seemed like there was equal flow. Maybe a little more restrictedz one came out a perfect stream and the bad one was a lot of water but not smooth stream.
 

swatski

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So I just disconnect the hose one both engines that I suspect being the issue. And then shot water from the inner hose towards to back drain hose. it Seemed like there was equal flow. Maybe a little more restrictedz one came out a perfect stream and the bad one was a lot of water but not smooth stream.
I forgot - does it overheat on the hose or only in the water?

 

Jmpicking

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It is overheating on the hose also, didn’t the other day but now it is
 

swatski

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It is overheating on the hose also, didn’t the other day but now it is
Sounds like it is a plumbing issue. Some shredded fiber from the rope causing a partial obstruction somewhere?

Given how it started, the worst case is unlikely - obstruction due to internal corrosion of the exhaust manifolds and passages, that’s a difficult one to fix.

 

Jmpicking

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Sounds like it is a plumbing issue. Some shredded fiber from the rope causing a partial obstruction somewhere?

Given how it started, the worst case is unlikely - obstruction due to internal corrosion of the exhaust manifolds and passages, that’s a difficult one to fix.

Yeah so I’ve taken a ton of the cooling sections off and shot water and air through them, nothing comes out. Also took a camera snake through as many hoses as I could and didn’t see anything . It seems like it’s coming from the one area of hose connected to thermostat that is overheating. It’s only 20 degrees hotter than the good engine. So i dont know if that’s enough for that to be the area of problem or not
 

swatski

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Darn... I wish I would have some advice, not sure what’s next.
Are you in salt?
@buckbuck @Scottintexas @itsdgm @Jgorm @Scottie, who else would know what to do? Time to pull the exhaust manifold to inspect the passages?

 

Scottie

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I haven't dug into the cooling system much, and I may be WAY off the base here, but.... If a car was having these symptoms, the thermostat would be a likely culprit, stuck closed, or not opening fully. I would check the thermostat if possible. This is off the cuff, so I apologise if it is wildly inaccurate.
 

swatski

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I haven't dug into the cooling system much, and I may be WAY off the base here, but.... If a car was having these symptoms, the thermostat would be a likely culprit, stuck closed, or not opening fully. I would check the thermostat if possible. This is off the cuff, so I apologise if it is wildly inaccurate.
He already swapped those though.
I tell you, this is a tough case.

 

Scottie

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Ahh, sorry. I skimmed the thread and didn't see it. I will read through again. From a troubleshooting perspective, I would pull the thermostat entirely. If it still overheats, then there must be an obstruction between intake and thermostat. If you can verify through the hoses that there is no obstruction, then the problem must be internal. I don't know if that's helpful or not, but that's how I would approach it.
 

Jmpicking

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Ahh, sorry. I skimmed the thread and didn't see it. I will read through again. From a troubleshooting perspective, I would pull the thermostat entirely. If it still overheats, then there must be an obstruction between intake and thermostat. If you can verify through the hoses that there is no obstruction, then the problem must be internal. I don't know if that's helpful or not, but that's how I would approach it.
Is this entire thing the thermostat, and if I pull this is that the thing that send the sensor to the dash that it’s overheating?
 

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Scottie

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Is this entire thing the thermostat, and if I pull this is that the thing that send the sensor to the dash that it’s overheating?
That is the thermostat, yes. That is not the temp sensor. The temp sensor will be resistive, with an electrical connection attached. I can't tell you exactly where it is offhand, but it is not part of the thermostat, and they function independently.
 

Scottie

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I know you've already swapped thermostats, so this may be a moot point, but you can put the thermostat in a pot of water on the stove and crank the heat. If the thermostat is working properly, you'll see it open. If it never opens, then it's faulty and should be replaced.
 

Jmpicking

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I know you've already swapped thermostats, so this may be a moot point, but you can put the thermostat in a pot of water on the stove and crank the heat. If the thermostat is working properly, you'll see it open. If it never opens, then it's faulty and should be replaced.
I did swap thermostats so I don’t think it’d be possible to be the thermostat at fault here. I still have the thermostat from the good engine in the overheating one.
 

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Before you do anything else be sure it is not a bad heat sensor I had one go bad, once the engine overheats it may damage a heat sensor. I believe that was how one of my sensors went bad, weeds overheated the engine and my son drove it in limp mode before he decided to remove the weeds, after that I had intermittent issues with warnings of overheating even on the hose but the non contact thermometer was not saying anything was actually hot so had one replaced and solved the issue. Either way have them checked or find the values and check them yourself
 

swatski

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That is the thermostat, yes. That is not the temp sensor. The temp sensor will be resistive, with an electrical connection attached. I can't tell you exactly where it is offhand, but it is not part of the thermostat, and they function independently.
Duh!
Thank you. Lol.

 

Jmpicking

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I took the thermostat out and it still overheated
 

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probably one sensor on the engine and one on the exhaust a parts schematic should say where it is you may even be able to swap those out
 
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