2005 honda crv coolant leak/heating issues

Thermostat temperature is 87 C so it's definitely intended to get hotter than 85.

If you have it mostly full and the heater is making heat, extensive "burping" should not be needed. Park on level ground, wait until it is completely cold, then before the next trip remove the radiator cap and check / top up the radiator. Do this a few times until you see it is staying full.

The sensor in the bottom of the radiator controls the fan. Thus it is driven by the temperature of the coolant in that part, not the engine. It takes a very long time sitting idling for the whole radiator to heat up enough so the fan trips on. It may never happen in cold weather. To confirm the fan works, you can unplug the sensor and jump the car side with a piece of wire. Fan should start immediately when the key is turned on. This is the larger fan, on the right side of the car. The smaller one only runs for the A/C. A/C should activate both fans, but that really can only be tested in hot weather.
 
Thermostat temperature is 87 C so it's definitely intended to get hotter than 85.

If you have it mostly full and the heater is making heat, extensive "burping" should not be needed. Park on level ground, wait until it is completely cold, then before the next trip remove the radiator cap and check / top up the radiator. Do this a few times until you see it is staying full.

The sensor in the bottom of the radiator controls the fan. Thus it is driven by the temperature of the coolant in that part, not the engine. It takes a very long time sitting idling for the whole radiator to heat up enough so the fan trips on. It may never happen in cold weather. To confirm the fan works, you can unplug the sensor and jump the car side with a piece of wire. Fan should start immediately when the key is turned on. This is the larger fan, on the right side of the car. The smaller one only runs for the A/C. A/C should activate both fans, but that really can only be tested in hot weather.

I checked this morning, the rad only need less than an oz to fill. reserve tank was half full.

Ill do this test later today, and thank you for the information!
 
You can also get the fan to turn on sooner by raising the idle and switching on ALL accessories that create a high amperage load (manual alternator output test) simultaneously (headlights w/high beams, rear defrost, blower on HIGH, etc.). This is how I used to do it at the dealer a long time ago and it worked everytime.
 
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Thermostat temperature is 87 C so it's definitely intended to get hotter than 85.

If you have it mostly full and the heater is making heat, extensive "burping" should not be needed. Park on level ground, wait until it is completely cold, then before the next trip remove the radiator cap and check / top up the radiator. Do this a few times until you see it is staying full.

The sensor in the bottom of the radiator controls the fan. Thus it is driven by the temperature of the coolant in that part, not the engine. It takes a very long time sitting idling for the whole radiator to heat up enough so the fan trips on. It may never happen in cold weather. To confirm the fan works, you can unplug the sensor and jump the car side with a piece of wire. Fan should start immediately when the key is turned on. This is the larger fan, on the right side of the car. The smaller one only runs for the A/C. A/C should activate both fans, but that really can only be tested in hot weather.

Alright I just finished jumping that wire harness for the radiator fan sensor. The big larger fan, which is on the left side near the battery, started immediately. The smaller thinner fan on the right side was inop. I carefully tried to push the blade to turn and it eventually did, but slowly and wobbling. It didn't sound good so I stopped the test.

SO the left larger fan works, the right small thin fan does not. I'll monitor it when it gets warmer out, and if i overheat/large fan doesn't operate in the summer safe to say its that radiator fan sensor?
 
Alright, little update.

Managed to swap in the new denso radiator, along with upper/lower gates hoses, oem spring clamps, thermostat, radiator cap, and replaced the reserve tank hose.

So far the temp on torque pro app stays at 77-78C. Does not dip into the 60s like before. If it matters the ambient temp outside is -14C/6F

However, the radiator fan does not kick on, I parked the car, idled for 15mins and the temp will slowly go to 85C with the heater off. I noticed steam coming out of the grill, but most likely from the water. I rinse off the bottom where the rad sits, and the plastic undertray. It contained coolant and some atf fluid from when I removed the hose from the cooler. Didn't try to go any higher. Not another expense =(
Frisco, the CRV's rad fan will only kick on at 105 C. Your temps are normal for winter....I seldomly see grater that. 82c when it's below freezing. In the summer, it should oscillate between 97c and 105c when idling.
 
Frisco, the CRV's rad fan will only kick on at 105 C. Your temps are normal for winter....I seldomly see grater that. 82c when it's below freezing. In the summer, it should oscillate between 97c and 105c when idling.
Thank you, so relieved about the information. Just a peace of mind from everyone's help that responded to the thread.


Thank you BITOG members!
 
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