94SRUNNER
GOLD Star
Its up!It was replaced with timing belt and water pump. Factory tstat. And before anyone asks, the giggle valve was correctly oriented. I forgot if it's up or down but i followed all the threads on mud when i did it.
Summer coolant temp?
- Thread starter Zooguy
- Start date
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Zooguy
SILVER Star
- Thread starter
- #22
This morning on my way to work the temperature was around 73° outside I drove the Land cruiser on the highway for about 4 MI to get everything up to temperature and then I took the speedometer up to about 82 mph and the temperature never got above 197°. On the way home the Land cruiser was indicating 96° outside and keeping it at 55 mph and the temperature got up to 208° f. I'm pretty mechanically inclined but I'm starting to get a little bit confused here
I am having a similar issue with my 2006 Tundra 4.7l v8 (high milage 290k+). Thought it was the wrong thermostat so I changed with oem thermostat. But even after that I saw Temps between 195 but then settled into 205-215 in multiple traffic types with stop and go. This was a 90° day. At stop saw the temp go up to 215.
The only major issue is that having the truck at stop and had it sitting to see what happens to the temps. And the temp guage climes to 235 after around 30-40 of of idle. So this is kinda an extreme test.
But wondering what I need to do next. Radiator is good not leaking. So I suspect a fan clutch. Any advise is appreciated.
94SRUNNER
GOLD Star
Are you sure the thermostat is functioning as designed? I.E. pulled and done the stove top test?
I've been watching my temps all day today. Literally 15 hours of driving while monitoring engine and trans temps. The engine temp can go up even in slower speeds depending on what the trans is doing, ie which gear and if the torque converter is locked. I had times with the engine temp lower, hauling 6k lbs at 70mph on relatively level roads, than other times while heading downhill at 55, but with the trans under a load.
I've never replaced my fan clutch but I'm going to now just in case.
Btw I'm also on 35s and have not regeared
When have you last cleaned your radiator
Complete new cooling system, 34s and 4.88s with a 5-speed tranny. I cruise around 190 in the cool months, up to 200ish when I'm cooking on the highway in the Summer. Highway speed around here is usually 75-85mph.
After trying to fix my Tundar's cooling issues here's what I think you have to do to troubleshoot this issue. List if from easy to harder. Please make your suggest if I am wrong as I am no expert. Just trying to resolve this issue as your all.
1. Take a note of your Radiator/Radiator cap & overflow tank - Does it have enough coolant? how does the coolant look (is it murky/brownish/dirty) you may have a dirty radiator that at the LEAST needs a coolant flush (cooling system flush) and cleaning. - Also bleed or taking the air out of the system (although I hear that Toyota's dont need bleeding) by going to a incline road or raise your front of the truck and take the radiator cap out and turn the heat on 100% and fan to low for about 10-15 min.
2. Test Radiator cap - Get the radiator pressure loner unit from Autozone to test if Radiator cap is holding pressure - (if cap is bad then replace - Our caps iirc should be holding 15-16psi/108kpa/1.1 Bar cap.) 16 psi-1.1 bar is oem. Thx @94SRUNNER
3. Test if Radiator is holding pressure - Same loner unit as above (if radiator is bad - Replace)
4. Test if Fan Clutch is running properly (non electrical fans only like our engines have )- How do you do this - 1. When the engine is cool - spin the fan, it should only spin 1-2 fan blades max maybe 3 (i.e less than 10-15% of a full fan turn). - 2. Then start your engine and immediately check the fan blades with a wad of paper/magazine - stick the paper wad into the fan and see if it stops. It should stop as the clutch should have not had time to engage. 3. Let the engine heat up to normal operating temp >160F and then do the paper wad into the fan blades again - This time after the engine is normal temp the fan blades should NOT stop. If they do then likely the fan clutch is BAD - Replace. 4. Stop the car and immediately check your fan blades and see how many times they are spinning... the fan blades should stop pretty quickly (max 2-4 full blades turns) since the engine is normal/hot temp and the clutch should have been engaged. If the fan continues to free wheel for around (5+ times), its likely the fan clutch again is BAD - Replace. 5. Lastly again right after you see if how long the fan blade takes to stop after turning the car off, Spin the fan blades again by hand and see how many times they spin... if the fan blades are free wheeling then again Fan clutch is BAD - Replace. - Check the below videos for more insights.
Here are some links on fan clutch testing Full way to test your fan clutch & 2nd link Hot engine fan blade test
5. Check Thermostat - Take out your thermostat and test it and see if it is working okay. I.e. stick it in boiling water and see if it opens. If not replace the bad thermostat with OEM (cause they are almost the same price as others). Make sure you have the giggle valve at the right place. For the 2uv-fe v8 4.7l it has to be on the 12 O'clock position.
Now if after testing and/or replacing the components above didn't improve your cooling then its likely you have
1. Your cooling system may have a clog/blockage of radiator (most likely) or somewhere else in the system
2. Lastly it can be your water pump. If you have come to this then ensure you do all the steps above, so only after this look at replacing the water pump.
6. Change Water pump and/or Radiator - if radiator was holding pressure but still having overheating issues Replace radiator (especially if its 10+ years old)
Hope this solves your overheating issues. BTW I am no expert so please give your suggestions.
1. Take a note of your Radiator/Radiator cap & overflow tank - Does it have enough coolant? how does the coolant look (is it murky/brownish/dirty) you may have a dirty radiator that at the LEAST needs a coolant flush (cooling system flush) and cleaning. - Also bleed or taking the air out of the system (although I hear that Toyota's dont need bleeding) by going to a incline road or raise your front of the truck and take the radiator cap out and turn the heat on 100% and fan to low for about 10-15 min.
2. Test Radiator cap - Get the radiator pressure loner unit from Autozone to test if Radiator cap is holding pressure - (if cap is bad then replace - Our caps iirc should be holding 15-16psi/108kpa/1.1 Bar cap.) 16 psi-1.1 bar is oem. Thx @94SRUNNER
3. Test if Radiator is holding pressure - Same loner unit as above (if radiator is bad - Replace)
4. Test if Fan Clutch is running properly (non electrical fans only like our engines have )- How do you do this - 1. When the engine is cool - spin the fan, it should only spin 1-2 fan blades max maybe 3 (i.e less than 10-15% of a full fan turn). - 2. Then start your engine and immediately check the fan blades with a wad of paper/magazine - stick the paper wad into the fan and see if it stops. It should stop as the clutch should have not had time to engage. 3. Let the engine heat up to normal operating temp >160F and then do the paper wad into the fan blades again - This time after the engine is normal temp the fan blades should NOT stop. If they do then likely the fan clutch is BAD - Replace. 4. Stop the car and immediately check your fan blades and see how many times they are spinning... the fan blades should stop pretty quickly (max 2-4 full blades turns) since the engine is normal/hot temp and the clutch should have been engaged. If the fan continues to free wheel for around (5+ times), its likely the fan clutch again is BAD - Replace. 5. Lastly again right after you see if how long the fan blade takes to stop after turning the car off, Spin the fan blades again by hand and see how many times they spin... if the fan blades are free wheeling then again Fan clutch is BAD - Replace. - Check the below videos for more insights.
Here are some links on fan clutch testing Full way to test your fan clutch & 2nd link Hot engine fan blade test
5. Check Thermostat - Take out your thermostat and test it and see if it is working okay. I.e. stick it in boiling water and see if it opens. If not replace the bad thermostat with OEM (cause they are almost the same price as others). Make sure you have the giggle valve at the right place. For the 2uv-fe v8 4.7l it has to be on the 12 O'clock position.
Now if after testing and/or replacing the components above didn't improve your cooling then its likely you have
1. Your cooling system may have a clog/blockage of radiator (most likely) or somewhere else in the system
2. Lastly it can be your water pump. If you have come to this then ensure you do all the steps above, so only after this look at replacing the water pump.
6. Change Water pump and/or Radiator - if radiator was holding pressure but still having overheating issues Replace radiator (especially if its 10+ years old)
Hope this solves your overheating issues. BTW I am no expert so please give your suggestions.
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94SRUNNER
GOLD Star
Just to be specific, the OEM is 1.1bar or 16 (15.95) psi
yeah I'd say you're not in danger there, but something is up
if I drive at 80mph in 73 degree weather my temp doesn't go above 186. Maybe 190 if I have A/C on (I'm using a bluetooth OBD reader with torque app FWIW. Probably not quite as accurate as a scangauge)
I had this issue for years in my 80 series. Temps creeping up at high speeds, especially bad when climbing. I never really figured it out but all if it were me I would look at radiator or something restricting coolant flow at higher rpms. Perhaps flush the system? Disclaimer - I'm no cooling system expert.
Zooguy
SILVER Star
- Thread starter
- #32
My Land cruiser has 175,000 mi on it when I purchased it at 153,000 mi I had the timing belt and water pump changed because they were still factory. At right around 168,000 MI I changed out the radiator because the factory one began leaking around the top plastic cap. So I can confirm 100%
Good/new coolant
10k old water pump installed at dealership
7k old radiator purchased from Amazon
I'm going to try a new radiator cap next
If that doesn't help then I'm going to get a new thermostat. I would assume the dealership would have put a new one in with the new water pump but I can't know that for sure.
Good/new coolant
10k old water pump installed at dealership
7k old radiator purchased from Amazon
I'm going to try a new radiator cap next
If that doesn't help then I'm going to get a new thermostat. I would assume the dealership would have put a new one in with the new water pump but I can't know that for sure.
Earlier in the Las Vegas valley, 122°F outside temp;
but wait, there’s more: Extreme heat in the West could break 200 records and produce temps up to 127 degrees - https://www.google.com/amp/s/www.nbcnews.com/news/amp/ncna1270903
but wait, there’s more: Extreme heat in the West could break 200 records and produce temps up to 127 degrees - https://www.google.com/amp/s/www.nbcnews.com/news/amp/ncna1270903
I'll play.
Just installed the scan gauge and was pleased to see pretty normal running temps, 140-160 ATF and 185-195 Coolant temps.
That was until I was crossing the Mexico border in a 3hr line with about 85 degree temps. About 30 minutes in I noticed engine and transmission temps creep to 214/217! I cut the AC and coolant temps came back to an acceptable 198 but transmission only settled to 208 and would bump up to 213 with every slight move forward. Needless to say it was a pretty hot and stressful boarding crossing.
Fan clutch seems ok from the magazine and resistance test but from how loud it spins when I start the car it doesn't really sound like it spins that fast when the engine is idling and hot, does that sound normal? Radiator was replaced by previous owner and is missing the foam insulation. Thinking I should just replace both. Waterpump and Thermostat were done in the last 20k with OEM parts.
That was until I was crossing the Mexico border in a 3hr line with about 85 degree temps. About 30 minutes in I noticed engine and transmission temps creep to 214/217! I cut the AC and coolant temps came back to an acceptable 198 but transmission only settled to 208 and would bump up to 213 with every slight move forward. Needless to say it was a pretty hot and stressful boarding crossing.
Fan clutch seems ok from the magazine and resistance test but from how loud it spins when I start the car it doesn't really sound like it spins that fast when the engine is idling and hot, does that sound normal? Radiator was replaced by previous owner and is missing the foam insulation. Thinking I should just replace both. Waterpump and Thermostat were done in the last 20k with OEM parts.
shtbrwn86
SILVER Star
Could a clogged heater core contribute to this? I ask because when I got my new radiator there was some gunk in the fluid (looked like bits of plastic maybe?) The radiator seems to be working fine and I haven't seen any more chunks in the coolant, but I wonder if the heater core is blocked up? It definitely doesn't get as hot as it should. Pretty warm I would say. I just wonder if a clogged heater core could disrupt the coolant flow enough to have an impact on coolant temps?
I know this is an old thread, but here's my data:
Summer trip from Seattle to Bend, OR, saw 188-192 on UltraGuage most of the time on the freeway. OAT was usually between 93-104. Temp would creep up to 204 at the highest doing 80 with AC on full. Saw it hit 205 once. The OCD in me just wants to get it down to 187, which I know it's capable of. My ultra gauge is being reprogrammed as we speak so I can start monitoring my tranny temps.
1999 LX
Newer OEM fan cluctch
New OEM thermostat (95% sure jiggle valve is 12oclock)
New OEM radiator hoses
New OEM heater Ts
New coolant
New Koyo radiator (no foam. yet)
New OEM radiator cap
Seems normal but it wouldn't be a bad idea to replace old parts. Really hot ambient temps with nowhere to blow the hot air and coolant and trans temps will rise.
Missed this Jerry sorry, the OBD Fusion app has two PIDs for the trans, I just decided to put up both. This year’s summer is not as hot as last year though.
Btw I have done a timing belt change with new radiator and new red Toyota coolant. Being summer in the south with 90° temps, I am now observing coolant temperatures of between 187-197 with average of 192-194. Very seldom my temperature does hit 199-200 but quickly comes back down to 194-195.
Btw after doing the timing belt I thought I was having a coolant leak. But after chasing a phantom leak and by keep on adding coolant to the extra coolant reservoir. I finally added enough coolant to get my system stable where the coolant reservoir didn't need more coolant. So essentially I didn't get all the air pockets (coolant burping) out of my coolant system. Even though apparently Toyota's don't need coolant burping I think it is very necessary to burp all the air out of your system to ensure stable coolant temperatures. BTW the before and after coolant burping temperatures were 198 avg before, 194 after. So it makes a difference.
Also in my observations summer coolant temps for our 4.7l engine should be anywhere between 185 to 205 on average. Maxing at say 215 depending on the condition of your coolant, thermostat, radiator age, engine burping, coolant cap.
If you constantly see coolant temps average above > 215° you may need to check your coolant system.
--- Transmission temp (outside temp was 70°) on 4-speed at 70 mph highway cruise was hovering around 132°-140°... when slowing down to 0 mph at an exit trans temp went up to 150-165.
**** Btw All temps given in °F
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