Wow..so alot has changed since the last time I've been here, I guess it's been about a year and a half. anyway.

I never had had any problems with my mini up until now: 86,000 miles into it. Recently, when sitting in Drive-thrus or long periods of idle, I've noticed that the temp. gauge shoots up to the top. When I start driving however, it goes back to normal, never overheating while I'm in motion.

From my prior experience I believe this would be the thermostat sticking, is this a correct assumption? I've experienced this before with the SR20 in my 240sx. I eventually replaced everything in the cooling system, radiator, hoses, thermostat, fluid, et. al.

Okay, so if it is the thermostat sticking, I assume I need a new one. I'll call M7 for that. Moving along, I then need to change it. I've searched and read that the housing for the thermostat is on the driver's side of the head. I however found it hard to find the results I want by searching. Does anyone have a write-up or pictures of where I can find the thermostat housing? I don't want to just go digging around. Can anyone point me in the right direction?

 

see if your fan is coming on .

 

fan's fine. forgot to add that.

 

You have checked the power steering fan too? If that is stuck, jammed or has a blown fuse your Mini will overheat when not moving.

Rich

 

but I think this is the way to do it....

If you have big hands, take out the airbox. If not, you can do the swap without removing the air box. At least take off the top part....

There are some connectors (electrical) that attach to a bracket. Undo the connector (I think it's for the 02 sensor). The part mounted to the bracket turns and comes out of the bracket. Remove it.

The upstream MAP sensor is next. Two hex bolts. Don't drop them!

There's a wiring harness loom that wire ties to a thinggy that plugs into the bracket as well. Cut the wire tie or pull out the thinggy (it's a bit of a pain.)

Now I think you can get to the three bolts that hold the thermo cover on. I don't know if you have to remove the hoses connected to it or not, I think not. Two of the bolts hold the bracket in place.

Take the bolts out, and then the cover will be stuck on because that what they like to do. Work it loose, bend it away from the head, and remove the thermostat and the gasket as a single unit.

The new thermostat mounts in the old gasket, but watch out! There are three bumps in the groove that mate with cut outs in the thermostat. This will make sense when you see it.

mount it up and reverse the above!

This is from memory, so if anyone else has items to point out that I screwed up, please post corrections...

Matt

 

have not checked power steering fan. When on the road today I will make sure the fans are running when I stop.

Dr. Obnxs - thanks for the rundown. If all is well with the fans I know where to move next. Hopefully the fans are not the issue- I've found that that is an expensive fix.

 

Dr. Obnxs said "The new thermostat mounts in the old gasket, but watch out! There are three bumps in the groove that mate with cut outs in the thermostat. This will make sense when you see it."

I like your write up, but...why not get a new gasket. The ones from the dealer come with them.

Chad

 

Is your year 02 or early 03? They were the years with the PS fan problem, the PS fan would jam blow a fuse under the hood which is also connected to the radiator fans, so if your rad fans are coming on and you have no fuse blown, later years resoilved this issue by wiring the PS f& Rad fans circuits to seperate fuses.From what you are saying it sounds more like your thermostat, good luck.

 

I don't think... If you do a stock replacement, you get the gasket, you get no choice. If you do the M7 thermostat, you don't get a new gasket....

But it's not a bad idea.... Still, if you move the M7 thermostat over to the new gasket, you still need to know about the alignment tabs.

Matt

 

okay...so, it seems like my mind was tricking me. the fans totally arent coming on. so...first I'll check the fuse for the PS fan. Which one is it? is it labeled on the fuse box under the hood?

 

P.S. fan fuse (40 amp) is under the fuse box (turn it over).
Also, try turning on the AC to see if the engine fan comes on. I think it's supposed to kick on no matter what the engine temp. It may help you narrow down your options.

 

will be checking that out today. will report back.

 

The power steering fan on my car was a 5 amp fuse. Is the 40amp fuse for the power steering unit itself?

There is also a "fix" that I had the dealer do to move the radiator fan to its own separate circuit and fuse.

 

FIX IT NOW!

If you have a very early car without the separate curcuits, then you have multiple issues to fix. What probably happened is the PS fan jammed or failed, and that cooked the fuse. Now you have no radiator fans. So when you change the fuse, you should disconnect the PS fan to see if you can get the radiator fans to run. If you can do that, then plug in the PS fan, and see if it pops the fuse. The relay may need to try to turn it on first....

Do you have any skills in this area? If so, you can route 12 V power to the fans one at a time to see if they run. If this sounds intimidating, then take it to a shop to fix it. Right now, you've got a car with little or no protection from overheating, and things could be nasty fast....

Also, there's a way to put your instrument cluster into diagnostic mode so that it's a real temp gauge...

Hold the ODO reset button down, turn the key to where you see it say "test 1"

Press the ODO reset button down a few more times till it says "test 19" Leave it there. It will cycle between "19 on" and "19 off".

When it's saying "19 off" press the reset button again, this will put you into the diagnostic computer....

Press the button till you get to "test 7" and stop pressing the button. It will eneter into test 7.0, which is a digital temp readout in degrees centigrade.

The slow speed fan turns on at 95 c, the high speed turns on at 101 C.

If I were you, I'd always put my car in this mode while driving to see what's going on wiht the engine to make sure it doesent get hot. The reason you're having problems in drive throughs is there's no way to shed the heat cause no air is running through the radiator.

Matt

 

to check the relay for the fans - is it in the fuse block to the right of the airbox? I have the alta intake and box, so I don't know if that means I do or don't need to take anything out to get at a different fuse box.

How do you tell if a relay is bad? is there any visual inspection for them as there is for a fuse?

 

one way to test a relay that should be actuating is to put your meter across the coil. if there is voltage but the relay isnt actuating then the coil is junk . if it is actuating yet you have no voltage to where you need it via the contacts on the relay then the contacts are bad .

 

herbie, I'm not too sure what you mean. are there any other ways to test it out?

it just clicked with me recently, i've had a lot going through my mind that has nothing to do with cars lately...but a few months ago, I was experiencing a problem where my fans would stay on after I shut the car off, and the only way to remedy it was to unplug the fan connection right by the plastic intake piece that ducts from the front grille, or disconnect the battery. This went on for about a week while I researched the problem until finally, it just 'fixed' itself. the car ran correctly for a while and now this.

If this helps with diagnosis/suggestions...sorry I didn't throw that in before.

 

Sometimes there is a similar relay in the block that can be exchanged. I have not looked at it and don't have any documentation now but it may be worth looking for a similar relay and trying it.

Rich

 

I figured that may be one way to do it. To make sure I'm looking at the correct fuse block...on my 02 MCS it should be the fuse box right to the right of the air intake surround of the alta intake?

 

yeah i think if you flip the main box over you'll find the fuse .. a relay needs two lines for power . a feed and return . they sometimes marked a and b , the contacts will generally have numbers . set your multi meter to volts dc . put a lead on a and a lead on b . if the temp requires the fan you should read a 12 v dc . if so and no relay action (clicking) then the relay coil is junk . if it's actuating yet no fan it's either the fan or contacts on relay. check power to the fan first though this is easier . then work back .

 

Now we know your year as you've finally mentioned it in post #19, you have the same problem as I had and described ( with some key errors sorry about that) in post #8. Changing fuses is going to do nothing, as soon as your PS fan comes on or trys to come on the fuse will blow (located under the hood by the air intake 5 or 7 amp I believe) and in turn not allow your rad fans to come on. If you are electrically inclined you could follow Dr Obnxs advice in post #14. Or buy a new PS fan and leave the wiring as is. The new PS fan has an improved shroud over the old one as to not let debris in as easliy causing it to jam and burnout which in turn blows the fuse etc etc. Or you can get the dealer to do the wiring reroute for you at your expense of course. I went with the new PS fan as it's improved over the previous one and the old one lasted 5 years. So I'm guessing I'd be good for another 5years at least. Good luck

 

where did you get the fan/how much? Further...where is this fan located?

 

anybody?

 

It's a dealer item, they should be able to give you a schematic to show you exactly where it is located, but it's under the engine bay next to the PS pump.

 

Fan easy to remove with car on ramps, two bolts if I recall correctly.