Not a good thing at all, that diesel will not like being that cool.
Wear is increased in a cold motor.
Wear is increased in a cold motor.
Re-defining when a car has "warmed up"
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Originally Posted By: mechtech2
supton -
It sounds cold - much colder than a normal modern car, for sure. . You may have a cold thermostat in there.
I don't think I could hold the radiator if it had been at 170F. I could comfortably reach between the fan blades and hold my hand on there. Heater core was able to roast me out of the car if I wanted it to. I've seen 160F (with very cold ambient air) indicated on a meat thermometer stuck in the center vent.
Maybe tonight I'll abuse the car and see how hot I can get it.
supton -
It sounds cold - much colder than a normal modern car, for sure. . You may have a cold thermostat in there.
I don't think I could hold the radiator if it had been at 170F. I could comfortably reach between the fan blades and hold my hand on there. Heater core was able to roast me out of the car if I wanted it to. I've seen 160F (with very cold ambient air) indicated on a meat thermometer stuck in the center vent.
Maybe tonight I'll abuse the car and see how hot I can get it.
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Originally Posted By: supton
Started, then drove 10 miles at 60mph, after which it hit about 160F. Coasted for quarter-mile for a turn, down to 142. Drove another 5 miles at 60mph, during which time I turned down the heat, and was rewarded with 170F. I had to coast a bit to get onto the highway, so I had to “get on it” to get up to 70mph, with an indicated water temp of about 165F or so. For the next 20ish miles it stayed between 170-180F – I saw 179F climbing one hill, and it could get down to 170F while coasting. I’d say I saw 173F for most of the time.
Sounds like your thermostat is also getting lazy, like mine. My Golf typically levels out coolant temp (via the Scangauge) at about 77ºC.
Started, then drove 10 miles at 60mph, after which it hit about 160F. Coasted for quarter-mile for a turn, down to 142. Drove another 5 miles at 60mph, during which time I turned down the heat, and was rewarded with 170F. I had to coast a bit to get onto the highway, so I had to “get on it” to get up to 70mph, with an indicated water temp of about 165F or so. For the next 20ish miles it stayed between 170-180F – I saw 179F climbing one hill, and it could get down to 170F while coasting. I’d say I saw 173F for most of the time.
Sounds like your thermostat is also getting lazy, like mine. My Golf typically levels out coolant temp (via the Scangauge) at about 77ºC.
Huh, 170F is about 77C, so, similar numbers. Ah, I think I understand now--thermostat is opening prematurely, mixing only a small portion of coolant. I've been thinking it's either open or shut. Duh. Cold enough that the radiator can stay cool yet have boiling hot engine I'd think--needs very little cooling this time of year.
Crud. Another repair for this car. Wish I had thought to ask to have this part changed at the last TB. It would have been easier to find this out, had VW not programmed the temp gauge to sit at the middle! Somewhere around 160F it hits an indicated 190F on the dashboard, and apparently stays on 190F indicated to probably the other side of 200+F. Nothing like lying gauges!
Crud. Another repair for this car. Wish I had thought to ask to have this part changed at the last TB. It would have been easier to find this out, had VW not programmed the temp gauge to sit at the middle! Somewhere around 160F it hits an indicated 190F on the dashboard, and apparently stays on 190F indicated to probably the other side of 200+F. Nothing like lying gauges!
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I played around with an IR gun with the Jeep a couple weeks ago. If I stop and beam the oil pan right after the coolant temp hits 200* and stops climbing, the oil temp is around 110 - 115*. Drive for another 5 - 7 minutes, and the oil temp is around 160*.
After driving normally for a while and not getting on it, it settled out around 190 - 195*. After beating on it a little bit on some backroads (not sustained heavy throttle), I got it up to 205 - 210*.
This testing was done in 35 - 40* weather, so it likely runs a bit hotter in the summer.
I generally consider it "warmed up" once the coolant temp has been showing full for about 5 mins in the summer, 8 - 10 in the winter. The oil pressure at idle settles down a bit once it's getting to 170+ oil temp (stock pressure gauge is terribly inaccurate, so it's hard to be exact), and the engine starts to feel a bit smoother and happier around that point, so I figure it's safe to take it to 3k rpm or so at that point, and I'll open it up and not worry after another 2 minutes or so. While it's still warming up, I keep it under 2500 rpm, and try to stay to around 1/3 throttle (no more than 1/2).
After driving normally for a while and not getting on it, it settled out around 190 - 195*. After beating on it a little bit on some backroads (not sustained heavy throttle), I got it up to 205 - 210*.
This testing was done in 35 - 40* weather, so it likely runs a bit hotter in the summer.
I generally consider it "warmed up" once the coolant temp has been showing full for about 5 mins in the summer, 8 - 10 in the winter. The oil pressure at idle settles down a bit once it's getting to 170+ oil temp (stock pressure gauge is terribly inaccurate, so it's hard to be exact), and the engine starts to feel a bit smoother and happier around that point, so I figure it's safe to take it to 3k rpm or so at that point, and I'll open it up and not worry after another 2 minutes or so. While it's still warming up, I keep it under 2500 rpm, and try to stay to around 1/3 throttle (no more than 1/2).
Originally Posted By: supton
Ah, I think I understand now--thermostat is opening prematurely, mixing only a small portion of coolant. I've been thinking it's either open or shut. Duh. Cold enough that the radiator can stay cool yet have boiling hot engine I'd think--needs very little cooling this time of year.
Right - the thermostat is opening prematurely instead of operating correctly and not fully opening until it gets to 87ºC (or whatever it's rated to do). Remember, it's a fully analog device - there's a little wax pellet in the thermostat that forces it open when it melts.
But if it's going to fail, this is the best way for it to happen. So I'd say it's working as intended.
Originally Posted By: supton
Crud. Another repair for this car. Wish I had thought to ask to have this part changed at the last TB.
It's pretty easy to change. A couple 1/4" extensions with a wobble joint at the end and it comes right out. Access in the PD TDIs is far, far better than I've seen in many cars including the ALH or 1.8Tnevrlose. And always replace the coolant temp sensor while you're at it!
Ah, I think I understand now--thermostat is opening prematurely, mixing only a small portion of coolant. I've been thinking it's either open or shut. Duh. Cold enough that the radiator can stay cool yet have boiling hot engine I'd think--needs very little cooling this time of year.
Right - the thermostat is opening prematurely instead of operating correctly and not fully opening until it gets to 87ºC (or whatever it's rated to do). Remember, it's a fully analog device - there's a little wax pellet in the thermostat that forces it open when it melts.
But if it's going to fail, this is the best way for it to happen. So I'd say it's working as intended.
Originally Posted By: supton
Crud. Another repair for this car. Wish I had thought to ask to have this part changed at the last TB.
It's pretty easy to change. A couple 1/4" extensions with a wobble joint at the end and it comes right out. Access in the PD TDIs is far, far better than I've seen in many cars including the ALH or 1.8Tnevrlose. And always replace the coolant temp sensor while you're at it!
Originally Posted By: supton
I remember doing the coolant sensor. I think I dumped half the coolant on the ground doing that. I guess since half has to come out to do the thermostat then it's a great time to redo that.
It's only $4 and you might as well change it while you have the cooling system drained.
Alternating 20 psi air into the coolant reservoir (with the drain tube capped with your finger) and then into the drain tube (with the reservoir capped similarly) helps get out another quart or two out of the block.
Also only use a new OE coolant flange, o-ring & thermostat. Aftermarket thermostats (even Behr or Wahler) don't have the locking tabs feature and almost all of the coolant flanges/thermostat housings that are aftermarket have some amount of mold misalignment or flash that cause the o-rings to leak.
I remember doing the coolant sensor. I think I dumped half the coolant on the ground doing that. I guess since half has to come out to do the thermostat then it's a great time to redo that.
It's only $4 and you might as well change it while you have the cooling system drained.
Alternating 20 psi air into the coolant reservoir (with the drain tube capped with your finger) and then into the drain tube (with the reservoir capped similarly) helps get out another quart or two out of the block.
Also only use a new OE coolant flange, o-ring & thermostat. Aftermarket thermostats (even Behr or Wahler) don't have the locking tabs feature and almost all of the coolant flanges/thermostat housings that are aftermarket have some amount of mold misalignment or flash that cause the o-rings to leak.
Originally Posted By: SteveSRT8
Just for grins, my good friend's stocker 370z routinely runs 220-230 in the city with normal driving. When whipped it just goes up until it hits limp mode.
Good to know, considering there aren't a lot of differences between the 370Z ad the G37. I generally drive like a grandmother, so I haven't hit limp mode yet.
Just for grins, my good friend's stocker 370z routinely runs 220-230 in the city with normal driving. When whipped it just goes up until it hits limp mode.
Good to know, considering there aren't a lot of differences between the 370Z ad the G37. I generally drive like a grandmother, so I haven't hit limp mode yet.
Here is my raw data from this morning's drive to work.
Total here 55 minutes. 1st third is city, middle 100km+, last third is 2 lane, 80km.
Total here 55 minutes. 1st third is city, middle 100km+, last third is 2 lane, 80km.
I always get a kick out of all the southerners who worry about warm up. In my powerstroke when the scangauge shows 20'C (68'F) I am driving away even if it is -40'C out. Obvously I am not hard on it at that temperature but the oil is still flowing. Lots of people who live where it really is cold like I do just get in and just drive away with no warm up. Use a good oil suited for the conditions and dont worry about it, racetrack operation notwithstanding.
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