Motorad 439-180 thermostat
#11
I just ordered this thermostat as well, not sure how much affect it will have with 118k miles already run at this temp.
Just got word from my mechanic that the front left and right rear head gaskets are leaking. Threw some stop leak in, and see how much more life I can get out of it. To my knowledge, the heads have never been done before.
#12
#13
re: Normal for my Rover at idle. (MY04)
Well, since the factory stat starts to open at 180, then fully open at 204; one would assume that any number of cooling issues could exist to make you warmer.
1. Rad half full of sludge, so just not enough internal surface area to transfer the heat. Check for fin tempeature more than 10F lower on the lower rows vs upper rows (not the side tanks).
2. Stat sampling holes filled up with some of that sludge, so the hot coolant that is sampled to warm up the main stat is reduced, just like you turned down the hot water on the shower. Only in this case, the stat stays closed longer, or does not open as far, so engine heat is not being disposed of. If replacing stat, be sure to do all your rad flushing and heater core before hand. Those holes are small.
3. Electric fan should be on at idle if 221. If not, why not (fuse, motor siezed, cut wire, or my favorite - reversed wires, so it blows out the front and subtracts cooling from the rad).
4. Fan clutch - when engine warmed up, and off, spin it by hand. If it coasts a whole revolution when released, time for another. Should feel like peanut butter inside, not PB Blaster penetrating oil.
5. Exhaust gas in coolant - bubbles under the dash plumbing. Steam does not convey temperature as well as water. Test by holding hand over boiling pasta. Pretty hot. Now plunge hand into pasta. No, don't do this! But you get the idea. Chemical test will confirm those bubbles are air or exhaust.
Good luck with the stopz leakz - may hold for a while.
Well, since the factory stat starts to open at 180, then fully open at 204; one would assume that any number of cooling issues could exist to make you warmer.
1. Rad half full of sludge, so just not enough internal surface area to transfer the heat. Check for fin tempeature more than 10F lower on the lower rows vs upper rows (not the side tanks).
2. Stat sampling holes filled up with some of that sludge, so the hot coolant that is sampled to warm up the main stat is reduced, just like you turned down the hot water on the shower. Only in this case, the stat stays closed longer, or does not open as far, so engine heat is not being disposed of. If replacing stat, be sure to do all your rad flushing and heater core before hand. Those holes are small.
3. Electric fan should be on at idle if 221. If not, why not (fuse, motor siezed, cut wire, or my favorite - reversed wires, so it blows out the front and subtracts cooling from the rad).
4. Fan clutch - when engine warmed up, and off, spin it by hand. If it coasts a whole revolution when released, time for another. Should feel like peanut butter inside, not PB Blaster penetrating oil.
5. Exhaust gas in coolant - bubbles under the dash plumbing. Steam does not convey temperature as well as water. Test by holding hand over boiling pasta. Pretty hot. Now plunge hand into pasta. No, don't do this! But you get the idea. Chemical test will confirm those bubbles are air or exhaust.
Good luck with the stopz leakz - may hold for a while.
Last edited by Savannah Buzz; 12-04-2012 at 11:04 AM.
#14
Yep, already cleared a clog in my heater matrix... that was easy enough with a garden hose and reverse flushing it.
radiator is new, thermostat (OE) is new, tank and filler cap are all new as well. fan clutch as well.
it did over heat (red self destruct light and all) once. very short period of time, immediately turned heater on and it went back to "normal".
considering my tapping noise, would it make sense while the heads are getting done to do the cam and lifters as well?
radiator is new, thermostat (OE) is new, tank and filler cap are all new as well. fan clutch as well.
it did over heat (red self destruct light and all) once. very short period of time, immediately turned heater on and it went back to "normal".
considering my tapping noise, would it make sense while the heads are getting done to do the cam and lifters as well?
#15
BG Findashop - Search for an authorized BG service center near you!
This is a safe stop leak product and the only one to use and I do not work for them
This is a safe stop leak product and the only one to use and I do not work for them
#18
#19
Are the euro stats stamped with opening temp or fully open temp? Are the American versions stamped the same? Maybe some keypunch conversion errors by the mass repalcement autoparts industry as well.
As for the D2 stat range, I saw that on page 421 of the shop manual:
As for the D2 stat range, I saw that on page 421 of the shop manual:
Thermostat - Main valve
The thermostat is used to maintain the coolant at the optimum temperature for efficient combustion and to aid engine warm-up. The thermostat is closed at temperatures below approximately 82°C (179°F). When the coolant temperature reaches approximately 82°C the thermostat starts to open and is fully open at approximately 96°C (204°F). In this condition the full flow of coolant is directed through the radiator.
I also saw this:
The thermostat is used to maintain the coolant at the optimum temperature for efficient combustion and to aid engine warm-up. The thermostat is closed at temperatures below approximately 82°C (179°F). When the coolant temperature reaches approximately 82°C the thermostat starts to open and is fully open at approximately 96°C (204°F). In this condition the full flow of coolant is directed through the radiator.
I also saw this:
In cold ambient temperatures, the engine temperature is raised by approximately 10
°C (50°F) to compensate for the heat loss of 10% exposure to the cold coolant returning from the bottom hose.
I'd like to know how that happens or if it is a typo. The stat is a mechanical device with no feedback to a IAT sensor, etc.
I'd like to know how that happens or if it is a typo. The stat is a mechanical device with no feedback to a IAT sensor, etc.
Last edited by Savannah Buzz; 12-05-2012 at 09:22 AM.
#20
The temperature variation is linked to ambient temperature by the thermostat being exposed. With it installed in an intake manifold, it is primarily subjected to engine temperatures only. With it hanging out in the air as it does on a DII, the thermostat housing and lower hose is exposed to the colder ambient air temperatures. In order fo the thermostat to open, the coolant flowing through the sensor holes has to warm up the coolant in the lower hose. If the coolant is colder to start with, it takes more hot coolant to open the thermostat. The delay in opening means that the coolant in the engine is hotter when the thermostat finally opens.
I imagine that this is just a side effect of their relocating the thermostat that someone decided to describe as if it were an intentional part of the design.
I imagine that this is just a side effect of their relocating the thermostat that someone decided to describe as if it were an intentional part of the design.