Generator running hot

[MyPrevost]

Good afternoon,

Since purchasing my coach in November 2006, I’ve noticed that the generator runs hot under load, reaching temperatures of 225°F. The radiator, which is located at the front of the coach, seems to be functioning, but I’m concerned about the high temperatures.

Here are the details:
– I’ve bled the radiator line multiple times to remove any air.
– Using an infrared thermometer, I measured the temperature of the line to the radiator at 225°F, and the return line from the radiator at 185°F.
– The radiator is expelling hot air, and the fan behind the radiator (which is mounted flat in the front storage area) appears to be working, as there’s a high volume of hot air being released.
– The antifreeze level and mixture are correct.
– The thermostat seems functional, as there’s flow to the radiator.

Despite this, it still runs hotter than what most suggest, which is around 200°F. Do you have any suggestions on what could be causing the generator to run this hot?

Thank you,

Kim Sloan
2002 Vantare XLII S2
2006 Dodge Megacab

[MyPrevost]

Suggestion: Remove the thermostat and place it in a pot of boiling water to check if it opens. If it doesn’t open, replace it with a new thermostat. If it does pop open, reinstall it and observe whether the overheating issue persists.

Tuga & Karen Gaidry
2012 Honda Pilot

[MyPrevost]

On the Liberty, proper placement of the baffle for the radiator cooling fan is crucial for maintaining adequate cooling for the generator. While I’m not sure if the Vantare has or requires a similar baffle, it may be worth checking to ensure proper airflow.

Keep us updated on your progress!

Mike

[MyPrevost]

Kim,

Mike is right: ensuring that the hot air exhausted from the radiator is completely isolated from the cool air entering the radiator is crucial. On the Liberty, the baffle system manages this well, and Vantare must have a similar solution in place. It would be worth verifying if this airflow separation is functioning correctly on your coach.

I agree with Tuga’s suggestion about checking the thermostat, but one thing you mentioned raises a concern. If you’re seeing 225°F on the outflow and 185°F on the inflow, it seems the coolant is already entering the engine at the desired temperature. If the thermostat is not stuck, could it be that it’s set for the wrong temperature? Or perhaps there’s no thermostat at all? In some cooling systems, the absence of a thermostat can result in coolant flowing too quickly through the radiator, preventing adequate heat dissipation.

Also, consider whether the radiator might be blocked or partially obstructed. Is the radiator fan working properly, or could it be cycling on and off due to thermal overload on the electric motor?

Have you contacted Vantare for their input on what might be causing this issue?

Good luck!

 

[MyPrevost]

There are several possibilities to consider.

Since your coach isn’t a Liberty, we can likely rule out the “MangoMike” disposable generator baffle as the issue—unless, of course, the Vantare conversion originally had one and it’s now missing.

The key factor here is airflow across the radiator. If the airflow is restricted due to low velocity or clogged fins, the heat won’t dissipate efficiently, leading to higher temperatures.

If you’re not losing coolant and don’t see any leaks, pressurizing the system to check for leaks might not be necessary. However, it’s possible the thermostat is stuck or not fully opening, which would reduce coolant flow through the radiator and cause the engine to overheat.

It’s also worth inspecting the radiator for internal buildup, although this is less likely given the coach’s age. Based on your measurements, there’s a 40°F temperature difference between the inlet and outlet, so if the target operating temperature is 185°F, returning coolant at 185°F indicates an issue that needs resolving.

[MyPrevost]

Good afternoon,

Since purchasing my coach in November 2006, I’ve noticed that the generator runs hot under load, reaching temperatures of 225°F. The radiator, which is located at the front of the coach, seems to be functioning, but I’m concerned about the high temperatures.

Here are the details:
– I’ve bled the radiator line multiple times to remove any air.
– Using an infrared thermometer, I measured the temperature of the line to the radiator at 225°F, and the return line from the radiator at 185°F.
– The radiator is expelling hot air, and the fan behind the radiator (which is mounted flat in the front storage area) appears to be working, as there’s a high volume of hot air being released.
– The antifreeze level and mixture are correct.
– The thermostat seems functional, as there’s flow to the radiator.

Despite this, it still runs hotter than what most suggest, which is around 200°F. Do you have any suggestions on what could be causing the generator to run this hot?

Thank you,

Kim Sloan
2002 Vantare XLII S2
2006 Dodge Megacab

 

Kim,

Based on what you’ve described, it sounds like your temperatures are actually normal, and the issue might be with the accuracy of your gauge. If your infrared thermometer is reading 225°F into the radiator and 185°F out, but the gauge shows 225°F overall, the gauge could be giving you an incorrect reading. Ideally, the generator should run at or below 200°F, so your readings seem reasonable if the infrared thermometer is correct.

JIM

[MyPrevost]

When you mention that the radiator is located “far away” from the generator, is there an auxiliary water pump to help move the coolant over that distance? It might be worth checking, along with what others have suggested, to ensure the coolant level is full when hot and that it’s circulating at the correct rate.

[MyPrevost]

Focusing on Liberty coaches—there was a time when the remote radiator had an electric coolant pump located at the radiator. In my current Liberty, the generator relies on its integral coolant pump. Even on the hottest days under load, my generator has never exceeded 180°F. It seems like Kim’s issue involves something less obvious that still needs to be identified.

[MyPrevost]

Thank you for all the responses!

I plan to test the thermostat tomorrow. There’s almost 30 feet between the generator and the thermostat, and the radiator appears clean based on visual inspection. Since the radiator is located at the front of the coach, there isn’t a baffle in that area.

I have a quick question: Could a thermostat that isn’t opening fully still allow the temperature at the radiator to reach the 225°F measured? We used two thermometers and got nearly identical readings.

I’ll also reach out to Vantare again tomorrow, but I’ve already contacted them twice without getting much insight into the problem.

Kim

[MyPrevost]

Kim,

I had a similar experience where my water temperature gauge read over 220°F because my thermostat wasn’t opening. After I removed it and placed it in boiling water, it seemed to clear up any issues. When I reinstalled it, it worked perfectly afterward. I also kept a new thermostat as a spare just in case the problem comes up again.

It’s an easy test to perform, and it might just resolve your issue.

Tuga & Karen Gaidry
2012 Honda Pilot

[MyPrevost]

They do make thermostats that fail in the open position rather than closed. It might be worth taking your thermostat to a reputable parts store or garage to discuss this option with them, as it could help prevent overheating issues in the future.

Also, consider looking for a booster pump. With a 30-foot run through a hose, the standard engine water pump might struggle to maintain adequate coolant flow. Keep at it—don’t let that engine get damaged!

Lastly, check all the hoses. If they’re soft, they can collapse and restrict coolant flow.

[MyPrevost]

What manufacturer is the generator? If you have the manual, check it for the specific thermostat model and order a new one. Replacing the thermostat first is a good way to eliminate it as a potential issue. If you still encounter problems after that, then the distance between the radiator and the engine should be the next aspect to examine.

[MyPrevost]

I agree with Gary—replace the thermostat without bothering to check the old one, as they don’t last long. Starting fresh with a new one is the best approach. Removing the old thermostat is the more significant part of the job, so there’s no reason to put back a cheap, perishable part that could fail again.

After replacing the thermostat, make sure to inspect the entire system, even if the issue turns out to be the thermostat.

JIM

As Will Rogers said, “I never met a man I didn’t like.”
And someone else noted, “I never had a thermostat that didn’t fail.”

[MyPrevost]

New thermostat in and no change.

Kim sloan

• This reply was modified 2 months, 1 week ago by MyPrevost.

[MyPrevost]

New thermostat in and no change.

Kim sloan

I recommend reaching out to customer support for your converter or generator manufacturer. Additionally, check if there are any other valves, sensors, or backflow preventers in the piping system between the radiator and the generator. These components could potentially affect coolant flow and contribute to the overheating issue.

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