Thermostat/overheating

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Thermostat/overheating

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Thermostat/overheating - 10/3/2005 3:45:45 AM

Gnashing

Posts: 6
Joined: 10/3/2005
Status: offline

A new poster, I have greatly enjoyed reading and looking over the entries/posts from members on this site. I have a '95 2.5L with about 160k miles. It still runs strong, but is starting to have a few issues as time marches on. Similar to post of Danattamco, lately it has been running hot with dash temp gauge pointing just below hot mark most of time. When I shut it down at end of ride, it often spews out hot steamy water on the ground (approx under battery area) for about a minute. I keep filling it up with water (in hopes a miracle might happen) but have decided to try and change out the thermostat. I started disconnecting wires, sensors, nearby parts, and still couldn't find a way to easily remove housing (of t-stat). Am I missing something? Usually replacing a t-stat is fairly straight forward and pretty simple operation, but it looks like I may have to remove plastic housing/cover of timing belt to get at the t-stat. Can that be right?

Maybe this chore is beyond an average DIY home-grown mechanic??

Thanks ahead of time for any input you all may have.

Post #: 1

RE: Thermostat/overheating - 10/3/2005 2:23:02 PM

babyhuey

Posts: 2759
Joined: 7/28/2005
Status: offline

Hi Gnashing. Sounds like you are on a good track except that I think you may be looking for the thermostat on the wrong end of engine. Unlike most engines that have the t-stat at the upper radiator hose, yours is located in the lower hose area. In order to change you will want to remove the air cleaner housing and inlet hose for access. The thermostat is located just below and to the rear of the distributor. Once the air cleaner is out of the way there are only three 12mm bolts to separate the t-stat housing. Don't forget the bolt that holds the metal connecting pipe to the block. Will post a picture that will help better than my ramblings. Dont forget the 'o' ring that seals the pipe to the housing cover. Is easy to overlook but oftentimes starts to leak once it has been disturbed. Should only be $6 or so from dealer.

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(in reply to Gnashing)

Post #: 2

RE: Thermostat/overheating - 10/6/2005 6:21:58 AM

Gnashing

Posts: 6
Joined: 10/3/2005
Status: offline

Hello babyhuey! Thank you so very much for the reply to my questions of frustration about the Millenia thermostat. I feel so stupid spending hours looking for something that's on the other side of the engine. Well, after a couple more hours (I'm a slow/deliberate amateur mechanic) working on the correct part of the engine detaching hoses, separating wire couplings, etc. I've gotten to the t-stat housing behind the distributor. Now I'm having a heck of a time trying to loosen the bolts on the housing. I'm beginning to believe the tales about Japenese cars leaving barely enough room for a small hand to dismantle something in the engine compartment. I only see two 12mm bolts (the diagonal ones) versus 3 that you mentioned. And I can't get a socket on them--just not enough space. My 12mm end wrench fits, but I just can't get enough leverage/torque to loosen them. It's really frustrating--I guess I shouldn't have taken on this project.

But thanks again for your help, along with the pik that showed the area very clearly. If you have any more thoughts on getting the housing detached, please let me know. I'm so close to getting to the t-stat I hate to give up

(in reply to babyhuey)

Post #: 3

RE: Thermostat/overheating - 10/8/2005 9:59:25 PM

babyhuey

Posts: 2759
Joined: 7/28/2005
Status: offline

Hi Gnashing. Don't give up and don't feel stupid about looking at the other end of engine. Most engines do put the t-stat in the upper hose and you were smart to go looking for it where it was expected to be found.You are doing fine. There are only two bolts that hold the t-stat housing together. The third attaches the metal pipe where the lower hose attaches to the engine block below the distributor. Socket will probably be out of the question as not enough room but an open end should get those bolts loose. Did you remove the air cleaner housing to gain better access? If not is essential in order to get your hands in there. I am 6'4" and hands to match so I know what you mean by tiny hands getting access. If your wrench is too short to get good leverage try using a piece of pipe to slip over the wrench and give you a bit more pulling power. You are turning counterclockwise to loosen right.

There is a way to increase leverage if you are using a box/open end wrench but will post a pic of how to do this instead of trying to explain.

(in reply to Gnashing)

Post #: 4

RE: Thermostat/overheating - 10/9/2005 5:46:08 AM

Gnashing

Posts: 6
Joined: 10/3/2005
Status: offline

Hi again babyhuey: Once again thank you so much for your help on my Millenia project. Your tips, advice and support are really appreciated--especially when I get so frustrated and think that I just can't do this thing! But after disconnecting some more hoses and wires, it all became clear what you were talking about. The third bolt attaching the metal pipe became visable and I was somehow able to loosen all 3 bolts--- that is, after buying a new 12mm box end wrench! What a difference proper tools make! A new Stant t-stat plus new O-ring gasket fit perfectly and I tightened everything down to finish up the project. Oh yes---the old t-stat did test defective, so at least I was on the right track in my initial diagnosis.

Now everything is back in place including hoses, wire junctions, etc. When I started the car it actually seemed to run smoother and quieter than before t-stat replacement. Maybe some of the wire/hose connections were improved--or maybe it's just my imagination, being so glad it's running OK after all the problems I encountered. A 30 minute test drive revealed no leaks/problems & temp gauge running steady in normal zone, just a tad higher than before. Many thanks again, baby huey----I couldn't have done it without your help. Gary

< Message edited by Gnashing -- 10/10/2005 5:46:17 AM >

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Post #: 5

RE: Thermostat/overheating - 10/10/2005 9:21:08 PM

babyhuey

Posts: 2759
Joined: 7/28/2005
Status: offline

Glad you were able to complete the project and all is working as it should. Good work!!