2002 BMW 325Ci Thermostat with Housing Assembly TRQ ECA92791

What's up, guys? I'm Andy from 1A Auto. In this video I'm going to show you how to replace the thermostat housing on this 2001 BMW 325xi. If you need this part or other parts for your vehicle, click the link in the description and head over to 1AAuto.com.

With the trunk open, over on the right side or the passenger's side, there should be a cover that goes right here. This vehicle doesn't have one, but you're going to want to remove that cover. Battery is located right here. First thing I'm going to do is take a 10 millimeter socket and a ratchet, loosen up this nut for the negative terminal. That's loose. Slide off the cable, slide it out of the way.

I'm going to take these push pins out right here. I'm just going to use some side cutters. Get this center pin, pull that up, and then slide it out. Be careful not to cut that. Get those out. Just grab this piece, slide it out. We're going to disconnect this connector right here. Just push down on that. Slide that out. There's another connector right here. I'm going to slide the wiring out first, just like that. And the connector will come out. Just slide that to the side like that.

I'm going to take a T25 and a ratchet. Take this screw out right here. Just going to use this trim tool from 1AAuto.com, take this push clip out. Get in there. Pull that out. All right, now that is loose. But what we need to do is we need to take the fan off, because the fan has to come out with the shroud as one. What we need to do to take the fan off is we need to disconnect the fan clutch from the engine side. This is attached to one of the pulleys right there. So sometimes these are somewhat difficult to get off. So what we're going to do is use this tool. We actually sell this at 1AAuto.com with many different sizes. This happens to be the 32 millimeter. That's going to slide on there. And then we slide this on. And with a pneumatic air hammer, we're going to give it a couple bumps, and it's going to loosen up that nut and we should be able to get it off.

All right, so now I'm going to take the tool. Now this fan clutch happens to be on their in reverse thread, so it's going to seem like you're tightening it, but you're actually loosening it. So it will go like that. Put our air hammer on there. Make sure you wear hearing protection and eye protection.

All right, so that's loose. Took a little bit of effort, but I got it. Now you can slide the tool off. Just move it a little bit. There we go. You should be able to just spin it off like that. Might need the tool once in a while. But you could use a wrench that fits, 32 millimeter wrench. All right, now I'm just going to keep loosening this up. Be careful, you don't want the fan to fall. You don't want it to smash into the radiator, and especially if you're going to reuse the radiator. If you're replacing it, it's not a big deal.

So, as I get closer to the end, I'll just move the fan and just grab the blade. And there we go. Now I can slide this right up. Just like that. Just going to disconnect this connector to the mass airflow sensor. Push down on this tab, wiggle it out. Take a straight blade screwdriver, loosen up this clamp right here. Should be good. Can push that snorkel off right there. And there's all these clips holding the top of the air box off. I'm just going to take the top off. And this last one over here, it's tricky to get to. Pull the dip stick out of the way. And just grab the air box, pull the air filter out.

I'm going to take these two bolts out and use a 10 millimeter socket, extension, and an electric ratchet. You can use a regular ratchet if you don't have an electric one or an air powered one. Loosen them up, take them out. Now just grab the air box, slide it up. And this wire is on it. There's a little grommet right here, just try to slide that out. Just try to slide this off. All right. Take that off. And just slide this out of the way.

I'm going to pull this fill cap off before we drain the coolant, make sure the engine is cold. You don't want to take this off while the engine is hot or you're going to get splashed in the face with coolant. Pull that off. And now we can raise the vehicle and drain the coolant.

Underneath the vehicle, there may be a cover right here. You're going to have to remove it. There should be some fasteners there, there, and there, and there. And the, also back there. Passengers there, there and there and there. And then, also back there. This vehicle doesn't have it, so we're just going to start right here. I need to loosen up this drain right here. This radiator is not the original radiator, so I believe you're going to have a different size socket to use if you have the OEM radiator. For this one, it's a 22 millimeter socket. I'm going to use an extension and a ratchet. Loosen this up. Make sure you put a drain bucket underneath. I'm just going to remove this. And there we go. That coolant looks nasty.

To help the coolant drain out a little faster, I'm going to open this bleeder screw right here. Just use a straight blade screwdriver. Loosen this up. All right, now we want to remove this side from the radiator. I'm just going to take a straight blade screwdriver, slide up under this retaining clip right there, and then there's also one right here. Just like that. Now I can just grab this hose and just wiggle it a little bit. All right, pry that off. That's good. Now I'll take the screwdriver and just take this hose off completely. And slide the clip out, just wiggle this back and forth. Pull it up.

Disconnect this connector right here, push on that, slide it out. Make sure you have your drain bucket underneath. And I'm going to pop this hose off. Just use a pic, slide up on the lock, and grab the hose, and try to wiggle it out. All right. Just a little bit of coolant, not too much. Now we're going to take this part of the hose off right here and just use a straight blade screwdriver or a pic. Pull the retainer out. You don't have to pop this off completely. Just happened to do that. And just grab it and wiggle it down. There we go. Slide it down and slide it out.

We removed this hose completely. You don't have to remove the hose completely, you could just pop it off on this side to do the thermostat. We're going to disconnect this connector right here. Just push on this little lock tab and slide it out. I'm just going to take a 13 millimeter socket and a ratchet, remove this bolt right here. There's four bolts in total. This one happens to be a 13. Pull that bolt out.

All right, I'm going to take this nut off because this bracket goes over the thermostat. I'm just going to use a 11 millimeter socket and a ratchet. Grab the bracket. So, this bracket, I can't get this bracket out. I'm just going to leave it loose like that. And then there's three 10 millimeter bolts I'm going to take out. Use a 10 millimeter socket and a ratchet. Now take these two out. Now, I did move my drain bucket underneath the engine so that if any of the coolant comes out you can catch it. All right, take this last bolt out. Now you can grab the thermostat housing, and just pull, slide it out of the way.

Here's the old part. Here's the new thermostat housing from 1AAuto.com. Has the same shape as the old one, has the same connector, has the same thermostat on the backside, and gasket. Get yours at 1AAuto.com and you'll be ready to rock and roll.

Just want to clean up this area around where the thermostat goes. Just going to use a razor blade, you can use a scraper. And you can wipe it down with a rag. Use a little brake parts cleaner on the rag, and just make sure the surface looks pretty clean. Now we're going to install the thermostat. I am just going to put a little bit of pipe sealer on these bolts. This is just personal preference. You don't have to do this. It works as a little thread locker, like a very light coat. Just do that on all the bolts. Take the thermostat, get lined up behind that bracket, and put the bigger bolt right here. Get that started and then I'll start these other ones.

I'll take a 13 millimeter socket, snug this one down. And 10 millimeter socket for the other ones. Now I'm going to torque the smaller bolts with a 10 millimeter socket and a torque wrench to 80 inch-pounds. Now I'm going to torque the bigger bolt. I'm going to use the 13 millimeter socket and a torque range. I'm still on inch-pounds. I'm going to torque this to 195 inch-pounds, which is equal to about 16 foot-pounds.

Just put this nut back on this bracket here. Then I'll take a 11 millimeter socket and a ratchet, just snug this one up. That's good. Take this wire. Reposition this the way it goes, and connect the connector. Lock it in place.

I'll take the hose, slide it in position, and just lock it in place on the lower radiator hose right there. It'll lock in place. Take the connector, line it up, lock that in place. We can take the upper portion of the hose, and slide it over here, lock it in place.

All right, take this pipe, this upper hose, and just line that up right there. Lock it in place. And then, over here, line this up over here. And just wiggle it a little bit. Lock that in place. Make sure this reservoir is locked in too. That's good. So these have to go on together. Just slide this in position. Once you get this close, I'm going to start to tighten up the fan. Now these fan blades, the fan clutch is reverse thread, so it's almost like you're going to be loosening it. There's really no easy way to do this. Just do it carefully. Once you get it started, it's a little bit easier. Make sure the fan shroud is in properly. That's good.

All right. If you have the ability to torque this nut for the fan, you're going to torque that between 22 and 29 foot-pounds. I don't really have that ability, so I'm just going to put this tool on there and just give it a little tap. That should be good. Right here there's a push pin that's going to go back in here. Slide that in position and lock it down. And on this side we're going to put this screw right here. Then I'm going to use a T25 and a electric ratchet. Tighten this down, just snug. I'll position this wiring harness right here. And we'll plug the connector in right here. Lock that in place. Now we're just going to slide this side of the lower air box in here. Yours may have something that this connects to. This vehicle doesn't. Just slides in position. And then this lower part slides there. And make sure these holes are lined up. Take these two bolts and get these started.

Take a 10 millimeter socket and a ratchet and tighten these down. I'm using an electric ratchet. If you don't have an electric ratchet, just use a manual one. Take the air filter and reinstall it. Now take the top part of the air box. I'm going to slide it onto the snorkel first. Just like that. And then there's all these clips. Take these clips, lock this part down, connect the mass air flow sensor, or air flow meter. Now we're going to slide this clamp right here. Take a straight blade screwdriver and tighten it down. Just snug, not too tight. Give it a shake, make sure it's good. Take this piece, slide this into the air box, just like that. And there's retainers right here. Take those push pins and lock them down.

Then we can take the negative side. Connect the negative side. Take the same 10 millimeter socket and ratchet, tighten it up. That's good. At this point, if you had that cover, you're going to want to put the cover back where it goes.

When adding the coolant, we're going to use a funnel. And you want to make sure you add the appropriate type of coolant. You can check your owner's manual. There is BMW specific coolant. Generally, it's blue coolant. We're going to add, we're going to fill up the reservoir. We're going to take this bleeder screw out. Just use a straight blade screwdriver or Phillips head. Just move that funnel. You could probably just loosen this up a little bit, or you can take it all the way out. Just like that. Set it aside. You want to fill this all the way up to the top and have coolant come bubbling out of the bleeder hole. Once it's coming out of there, we're going to re-install the bleeder screw. It is plastic, so be careful, you don't want to strip this.

Get this started again. Then close that bleeder screw. And then you're going to adjust the level in here. Now there is a little dipstick in here. When this is full, this is going to be all the way at the top. Now, you can check it right here. It shows where the min and the max is, so you want to adjust that accordingly. You can add coolant or take out coolant. You can use a turkey baster or some type of fluid pump to suck the fluid out. Then you want to let it run. You want to leave the heat on. When you leave the heat on, if you don't have heat, you're going to want to crack this open a little bit, and just make sure you get some of the coolant out. It's probably a good idea to shut the engine off, let it cool down, and readjust your coolant.

When you're done, when the fluid level's at the appropriate level, take the cap, put it back on. Make sure you monitor your temp gauge while you're running the vehicle. If you run the vehicle for about 10 minutes, the temp gauge should go right in the middle there. If it starts going to the red, shut the vehicle off and start over. Bleed the system again.

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