# Stock Thermostat temp?



## jamesm113 (Jun 20, 2010)

What temperature does the OEM thermostat open up at? I have a 99 Sentra GXE

I think the PO put in too low of a temperature.

Thanks!


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## jdg (Aug 27, 2009)

Not exactly sure what they are SUPPOSED to open up at, but both of my B14's ('97 Sentra GXE & '98 200SX-SE with GA16DE's) run at about 184F, just a hair short of halfway up the scale.


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## jamesm113 (Jun 20, 2010)

Mine takes a long time to warm up on the temp gauge - for probably the first 10-15 miles, it's just above the C mark, though on longer extended drives, it will get closer to the midway point. My subaru warms up much quicker - usually within the first mile.


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## jdg (Aug 27, 2009)

Ya, that's entirely too long for a warm up. I'd bet the thermostat is stuck open, which isn't necessarily a bad thing, at least it's better than being stuck shut. Both of my B14's will warm up in about 5-10 minutes even in the coldest of cold weather (i.e. -20F and lower).
Pop the radiator cap, start the engine, watch out so you don't get sprayed with coolant. If the thermostat is stuck open, you'll likely be able to see coolant flowing thru the radiator. If you're lucky, you might even be able to give the upper hose a squeeze with the engine running and actually feel water flowing. If that's the case, then I'd say it's stuck open.


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## jamesm113 (Jun 20, 2010)

Ok, I'll give that a try. How do the stant superstats work with these cars?


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## motoman740 (Jan 17, 2011)

the same thing happened with mine, I replaced the thermostat and problem solved! BTW, replacing the thermostat is a PITA!


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## jdg (Aug 27, 2009)

2 small tips for swapping thermostats...
Pull that one power steering line that's clamped to the front/right strut tower and kinda push it out of the way.
Disconnect the front/right (passenger side) motor mount and jack up the engine a bit. Not enough to put a bunch of stress on the other mounts, but just enough to take the slack out of everything else.
I think it makes it bunches easier to get your hands back in there to get the 10mm bolts out with a ratchet/socket/and the right extension.
The block drain is under the exhaust manifold and looks like it's probably usually rusted in place so if you plan on flushing out your cooling system, now might be the perfect time to do it with a garden hose shoved in where the thermostat goes and the radiator drain out.


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## jamesm113 (Jun 20, 2010)

The FSM calls for "Nissan Genuine RTV silicone sealant part no 999MP-A7007"... can I use a permatex product instead, like the Permatex 22071 Water Pump & Thermostat Housing RTV Silicone?

EDIT: Also, the thermostat i got doesn't have a jiggle/bleeder valve, should i drill a hole in it?

Thanks,


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## skeeter123 (Apr 30, 2010)

OEM thermostats are 170-deg (per FSM); but A-Zone et al will hand you a 180-deg unless you know to ask for the 170...


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## jamesm113 (Jun 20, 2010)

Uh oh. I already bought a stant 180F... Will the 180 harm anything?

Every after market one I can find (gates, motorad, CST, stant, murray) say 180 is the OE temp except beck/arnley (which says 170). I remember reading in the FSM (for the 99 GA16DE) that the thermostat should _start_ to open at 170F, but didn't think that meant a 170 temp.


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## jamesm113 (Jun 20, 2010)

I just called the local dealership. The parts guy checked with a tech and the tech said it was 180F. The OEM tstat was also $37.34 and not in stock. Hmmm......


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## LvR. (May 26, 2010)

Stats are rated ito full open temp................... and if your cooling system is sound and the stat is really in control of your engine temp, that is also the temp you should be measuring on the stat's housing with an engine at normal operating temp (IR thermometer)


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## jdg (Aug 27, 2009)

170 or 180, I would think either one would be just fine since I replaced mine with a 180 as well. 10 degrees hotter doesn't hurt me any and as I stated above, both of my B14's run between 179 and 184 year 'round.
As far as the jiggle valve/hole, if it was me, yes, I would likely drill a small, maybe 1/8" hole in it.
And the sealant...just use a good quality sealant. Personally, I prefer the gray Permatex. Hasn't failed me yet.


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## smj999smj (Jan 1, 2006)

jamesm113 said:


> I just called the local dealership. The parts guy checked with a tech and the tech said it was 180F. The OEM tstat was also $37.34 and not in stock. Hmmm......


If your dealer wants $37 for that thermostat, they're ripping you off! The thermostat is P/N: 21200-77A63 and MSRP's for $22.63. It's available from online sources for around $16:

21200-77A63 - Nissan THERMOSTAT


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## jamesm113 (Jun 20, 2010)

Wow that was a huge PITA. Getting the 3 housing cover bolts off wasn't too bad but getting the radiator hose off the housing cover took me at least an hour and half.

Anyway, the old thermostat was stuck partially open. It was a Nissan one and had a jiggle valve and had 76.5C printed on it, so skeeter was right, the OEM are 170F.

I ended up just using the Stant Superstat 180F, and drilled a little hole (i think 1/16") on it to replace the jiggle valve.

Thanks for everyones' help!


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## jdg (Aug 27, 2009)

I was able to swap out mine without pulling the hose off....mainly because I got tired of trying to get the hose off after about 1/2 hour worth of dickin' with it, and I just bent my arm in a couple of extra spots to get the old sealant off and new stuff one there.
Sure ain't like doing an old small block Chevy thermostat...


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## skeeter123 (Apr 30, 2010)

Same deal... I had planned to take off the hose and clean it up (it had/has a bit of dried-coolant crud on it) but it was such a PITA I just replaced the thermostat and left the hose as-is (but tightened the clamp) No additional leakage, been ~30k miles....

I won't take credit for "being right" about OEM temp.... just read the FSM. It's amazing that they put all that useful info in one place....

Now some of my own thoughts: just as the "aftermarket" has decided that 180 is the new 170; I think it's possible that they're selling generic/non-OEM performing ETC's as well. I replaced mine as part of my extended tune-up, it now always reads a notch below half on the "gauge" (mine doesn't have temp #s). I suspect that from the factory, with an OEM thermostat and ETC, that it would be right at half-way mark... Can anyone set me straight on that? Do other models have gauges with #'s? Father's day is coming up, maybe I'll get one of those laser-thermometers (fingers crossed). 

I also don't think that 180/170 makes much difference, as long as everything else is working OK. The PCM does take engine temp into account somehow when doing its job (part of which is determining fuel mixture). 

Hope this helps.


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## smj999smj (Jan 1, 2006)

I've noticed on Nissans that when using aftermarket thermostats, the gauge tends to read a little cooler whereas the Nissan thermostats tend to put the gauge needle almost dead center. Also, the higher temp rated thermostat will give you better heater performance in cold-weather , but otherwise not a big factor for street driven vehicles.


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## skeeter123 (Apr 30, 2010)

test test test


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## jdg (Aug 27, 2009)

The temp gauges on both of my B14's have a little tiny tick mark on the face of the gauge near the center of the needle. And that's where my needle almost always sits.
A guy could almost never notice it if the needle sits over the top of the mark all the time.


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## jamesm113 (Jun 20, 2010)

Update: A Stant rep told me that Nissan has changed the "OE" temp "a couple times," so I think that explains there being both 170F and 180F thermostats out there.


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