Two Stage Thermostat
01-30-2015, 06:10 PM
#21
01-30-2015, 09:24 PM
#22
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Its straight from the dealership and guy said it was the two stage..
either way you can clearly see the difference in quality.
My truck runs a touch cooler at operating temp and my heat inside is hotter. And it opens when is should as the stant would sometimes wait too long and the truck almost overheated.
either way you can clearly see the difference in quality.
My truck runs a touch cooler at operating temp and my heat inside is hotter. And it opens when is should as the stant would sometimes wait too long and the truck almost overheated.
01-31-2015, 12:46 AM
#23
That sure doesn't look like any two stage thermostat that I've ever seen.
Maybe the salesman was counting open and closed as the two stages 
Notice the extra part hanging off the side? That's actually a separate opening that is regulated at a different temperature, hence two stage.
OEM Toyota P/N: 90916-03070
Last edited by Odin; 02-01-2015 at 06:02 AM.
02-02-2015, 05:15 AM
#25
Question: “Why does my engine temp go all the way up to the red before it comes back down to the middle of the gauge after I start it up in the morning. It only does this when the engine is cold and once it warms up it seems to operate normally. Could it be as simple as a stuck thermostat?”
“What happens on the 22R and 22RE engine, when the coolant goes through the heater core it gets cooled off enough that when it gets dumped back in on top of the t-stat it shuts it. Therefore the temperature in the engine continues to go up. The t-stat that I have mentioned has two valves in it, one at the regular temp. and one smaller on at a cooler temp. If the cool water shuts the big one, the smaller one stays open. All this happens because of the lack of a by-pass hose, which on other systems, keeps hot coolant running on the t-stat.”
You can get the two-stage thermostat mentioned above from your local Toyota Dealer.
Part Number: #90916-03070
“What happens on the 22R and 22RE engine, when the coolant goes through the heater core it gets cooled off enough that when it gets dumped back in on top of the t-stat it shuts it. Therefore the temperature in the engine continues to go up. The t-stat that I have mentioned has two valves in it, one at the regular temp. and one smaller on at a cooler temp. If the cool water shuts the big one, the smaller one stays open. All this happens because of the lack of a by-pass hose, which on other systems, keeps hot coolant running on the t-stat.”
You can get the two-stage thermostat mentioned above from your local Toyota Dealer.
Part Number: #90916-03070
02-08-2015, 04:00 PM
#26
I was losing coolant in the area of the thermostat. I'm not certain if coolant can leak out around the bolt holes. But it was either leaking around the rubber gasket or from one of the bolt holes. I think the rubber gasket wasn't thick enough. I swapped the gasket for a Stant 30988 gasket which is noticeably thicker. Also going through my 1.6l vw exhaust stud bin, I found some studs that were a good match for the thermostat bolt holes. I've read this is a M8x1.25 thread...I haven't confirmed it yet, but my vw studs were the right thread. The threaded portion of the stud that goes in to intake is 7/16", I put some pipe dope on that. The bare part of the stud is 1/2", I was able to use a regular set of pliers to grip and tighten it. The overall length was 1 7/8", a little longer than necessary but not a problem. I sure someone could find something that works even better...I was going to check out GM pn:21006166 which was used on Saturn 1.9l and has a Torx tip? The Torx tip should make removing and installing the stud easier. The vw stud seems to work very well and it is going to make it easier to access the thermostat in the future...for example if I want to remove it to flush the cooling system.
Last edited by chuckross1957; 02-08-2015 at 04:21 PM.
02-08-2015, 07:29 PM
#27
I was losing coolant in the area of the thermostat. I'm not certain if coolant can leak out around the bolt holes. But it was either leaking around the rubber gasket or from one of the bolt holes. I think the rubber gasket wasn't thick enough. I swapped the gasket for a Stant 30988 gasket which is noticeably thicker.
Not sure how I feel about the Saturn stud Vs. standard. I might just go with standard
Last edited by Odin; 02-08-2015 at 07:39 PM.
02-08-2015, 08:14 PM
#28
I think it is important to have a bare space in the middle to act as a stop. Some of the studs I looked at had 1/2 inches of thread and it was too much...the stud would hit the bottom before it hit the bare spot. 7/16 inches seems just about perfect. Of course I could have used a grinder and removed a little off the end of the ones that were 1/2". The one on the right in the photo looks good but it has about 9/16 inches of threads on the bottom. I think you need an E7 Torx socket for the tip. There was a guy on youtube who made a socket using a T35(?) torx bolt salvaged from a GMC safari van. I'm trying some heavy duty lined clamps on the upper radiator hose. I trimed 1 3/4" off the end of clamps and rounded the edges off.
Definitely heavy duty 9/16" wide instead of 1/2". I was using an aftermarket gasket...The Stant gasket looks similar to the Toyota one in the photo with the two stats.
Last edited by chuckross1957; 02-08-2015 at 08:47 PM.
02-08-2015, 10:06 PM
#29
It's kinda unlikely in this application but if it happens there'll be plenty of meat to get some locking pliers on it.
Last edited by Odin; 02-08-2015 at 10:11 PM.
02-09-2015, 05:00 PM
#30
http://www.stanleyfasteners.com/cata...og/pg_0062.htm I took a closer look at my stud and it sticks out 1/2" past the nut...so the overall length could be about a 1/4" shorter but not much more. Mine is 1 7/8', so you can't go much less than 1 5/8" overall and than doesn't include the torx tip. I don't think either of those in the photo are long enough. There is a longer version of the saturn stud. The gm part # is 21006951, in the above link the part # is 18514. I'm not sure if it could be modified to work or not. It looks like if you find the right vendor you could buy a bag of 25 real cheap. I think gm has discontinued the part.
02-09-2015, 05:15 PM
#31
http://www.stanleyfasteners.com/cata...og/pg_0062.htm I took a closer look at my stud and it sticks out 1/2" past the nut...so the overall length could be about a 1/4" shorter but not much more. Mine is 1 7/8', so you can't go much less than 1 5/8" overall and than doesn't include the torx tip. I don't think either of those in the photo are long enough. There is a longer version of the saturn stud. The gm part # is 21006951, in the above link the part # is 18514. I'm not sure if it could be modified to work or not. It looks like if you find the right vendor you could buy a bag of 25 real cheap. I think gm has discontinued the part.
Found a Fiero site that listed both the VW stud and the longer Saturn stud PT#21006951 as popular part numbers.
Apparently the VW stud was popular then they started using the longer Saturn stud because the stock ones would snap if you looked at them funny. Maybe if we can find out what they're using instead that would be the final answer?
Last edited by Odin; 02-09-2015 at 06:25 PM.
02-09-2015, 08:18 PM
#32
http://www.germansupply.com/home/cus...at=297&page=20 This substitute part # n014427R should work if the photo is accurate, might have to grind a hair off the end. Dorman p# 966-333 is M8-1.25x45mm and looks to be a good fit with out any grinding...I don't how hard it is (grade). I not sure if the longer saturn stud is doable or not. I'd bet the parts man at a vw dealership could hook you up with a couple of exhaust studs for a late 70s dasher with the 1.6l engine. I'm not sure why some of the vw studs that I have are slightly different. The one I used is longer than the normal exhaust stud by an eighth of an inch and the bare section is about twice as wide.
Last edited by chuckross1957; 02-09-2015 at 11:22 PM.
02-09-2015, 08:27 PM
#33
ARP has a really nice SS stud kit that comes with 4 in a pack, studs, washers, and nuts.
The problem is it's $48+
http://arp-bolts.com/kits/ARPkit-det...?RecordID=2099
The problem is it's $48+
http://arp-bolts.com/kits/ARPkit-det...?RecordID=2099
Last edited by Odin; 02-09-2015 at 09:23 PM.
02-10-2015, 09:43 AM
#34
I think we have a winner with the Dorman 966-333, about $3 for a pack of three and it doesn't require any modification. I checked all the measurements and I don't see any problems. The short threaded side is a little less than 7/16" so there shouldn't be any problems with it bottoming out. http://www.dormanproducts.com/itemde...SEName=966-333
02-10-2015, 12:37 PM
#35
Registered User
A couple of years ago, my radiator leaked in my 1993 22RE p/u so I replaced it and the thermostat with a Stant 190 degree (FSM says use 195 deg). I noticed the temperature gauge goes up almost 1/2 way then drops to about 1/3 way when it opens. Last year I did the timing chain replacement along with hte water pump, etc., but replaced the thermostate with a OEM Toyota. The temperature rises to about 1/3 and stays there all the time except when I stop and turn off the engine. When I return and start the engine up after being gone several minutes, the temp gauge rises to 1/2 way and drops back down to 1/3. It's an OEM Toyota part but doesn't look like the two-way one in the photo above. It looks like a normal single stage unit.
The moral is go with an OEM Toyota thermostat.
The moral is go with an OEM Toyota thermostat.
Last edited by anndel; 02-10-2015 at 12:39 PM.
02-11-2015, 09:32 AM
#36
HOWEVER, Summit has it listed as 10.9. They have been wrong about specifications of their products before that's for sure!
http://www.summitracing.com/parts/rnb-966-333
Last edited by Odin; 02-11-2015 at 09:36 AM.
02-11-2015, 05:16 PM
#37
Probably no better than grade 5 since they don't listed on their site.
HOWEVER, Summit has it listed as 10.9. They have been wrong about specifications of their products before that's for sure!
http://www.summitracing.com/parts/rnb-966-333
HOWEVER, Summit has it listed as 10.9. They have been wrong about specifications of their products before that's for sure!
http://www.summitracing.com/parts/rnb-966-333
02-11-2015, 05:40 PM
#38
Ha, I didn't look at their catalog. I thought they'd have the specs provided under the regular part number. Strange
But yea 10.9 is plenty strong for our intended use.
But yea 10.9 is plenty strong for our intended use.
Last edited by Odin; 02-11-2015 at 05:41 PM.
02-14-2015, 05:10 PM
#39
It is a little tricky trying to find studs that will work with out requiring modification. I hope this progresses to the point that we have confirmation of a part # that accomplishes this. I have another part #, I'm trying to confirm that this one is a M8-1.25 and that the photo is correct for the actual stud. This is a premium stud for use on turbo 2000-2003 Volvo S40.
I'm posting a link to a couple of photos of the 48mm/ 1 7/8" long studs that I installed, we can see if any one finds the extra length offensive. http://s1223.photobucket.com/user/chuckross1957/library/48mm%20Thermostat%20Studs%2086%20Toyota%20PU?sort=3&page=1
Last edited by chuckross1957; 02-14-2015 at 05:20 PM.
02-14-2015, 10:49 PM
#40
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I see the thread has moved onto finding better replacement studs, however I just figured I'd throw in my 2 cents. The two stage Toyota t-stat is the best t-stat I've had in the three Toyotas I've had. One being a 84 22r pickup, second being a 88 22-re pickup and third being a 87 22-re 4runner. Keeps the temp at 1/3 on all three rigs in both summer and winter. Worth every penny.
