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FAQ / REFERENCE => How-To's => Topic started by: Zoso on March 10, 2006, 10:02:51 AM

Title: DIY Thermostat and Coolant Replacement
Post by: Zoso on March 10, 2006, 10:02:51 AM
http://zoso.no-ip.org/318i-thermostat.html
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on March 16, 2006, 09:28:27 AM
Mike,
       Did this wind up helping your fuel economy?  I'm seeing almost the exact same indications out of my car right now.  Temp rarely leaves the blue, poor heat on really cold days.  At first I thought it might just be the guage, but the other day, when it was 75 outside, the temp went up to the middle.
 
I've been getting ~21 mpg in strict city stop and go driving and 26 mpg in mixed city/highway driving, and this looks like my next step.  I already replaced the plugs, O2 sensor, fuel filter, and air filter.

Just wanted to know how that worked out for you, since you don't say on your page.  Thanks
Brian
Title: DIY Thermostat and Coolant Replacement
Post by: Zoso on March 16, 2006, 09:48:16 AM
I do believe that it helped my economy, although I never took the time to calculate the MPG before and after.  After the new coolant and thermostat, I was able to go 400+ miles on one tank a few times.

Perhaps it is a placebo effect though... but better fuel economy makes sense.  For the engine to run at it's optimum, it needs to be at a nominal temperature.  Since I've gotten the new thermostat and blue BMW coolant in the car, it really stays a hair under or at 1/2 way all the time now.  I suspect someone put an 80 degree thermostat in your car too.

The parts aren't that tough, but the procedure was somewhat of a pain for me since I couldn't get the fan off.  With the fan off, this should be a snap.

The worst you'll do is normal maintenance on the car!
Title: DIY Thermostat and Coolant Replacement
Post by: kowalski on March 16, 2006, 01:35:22 PM
hmm, well maybe ill adjsut the temp on my fan, let the engine get a littler warmer, maybe up to half or so..
Title: DIY Thermostat and Coolant Replacement
Post by: nickmpower on March 18, 2006, 09:11:35 PM
Your thermostat is probably broken if it never leaves the blue. I have seen several cases where they have failed at around 130k miles. The one you get from the dealer is a new updated version.

do you happen to know the capacity of the system?
Title: DIY Thermostat and Coolant Replacement
Post by: Zoso on March 19, 2006, 05:40:16 PM
Sorry, I don't know. The first time I put the system back together, I didn't seal it right so most of it fell to the ground.  With all that spilled, and the 50% mixture, I still had enough with one 1G jug.
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on March 26, 2006, 02:29:30 PM
Finally got around to taking care of this today.  It looks like the thermostat was my problem.  After a test drive it looks like my temp is between 1/2 and 3/4 on the gauge  I'll report back in a couple of weeks on my mileage.

Brian
Title: DIY Thermostat and Coolant Replacement
Post by: Zoso on March 26, 2006, 07:04:46 PM
Nice.  

Did you take your fan off or did you squeeze yours in between the fan blades like I did?  If you did take the fan off, what tool did you use?
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on March 26, 2006, 07:39:58 PM
I wasn't able to get the fan off either, although I really didn't try very hard, since all I had that size was an adjustable wrench.  Belive it or not, I wound up taking the whole radiator out.  It came out a lot easier than I thought it would.  So far no leaks, but I'll be keeping an eye on it for the next couple of weeks or so.  Thanks for the help, btw.

Brian
Title: DIY Thermostat and Coolant Replacement
Post by: twinpop171 on March 26, 2006, 10:05:40 PM
Quote from: Zoso
Did you take your fan off or did you squeeze yours in between the fan blades like I did?  If you did take the fan off, what tool did you use?


I used a large adjustable wrench with a long cheater pipe when I did my water pump and thermostat last summer.  It was still a bitch to break loose and a little scary praying that nothing slips.:eek:

FYI my temp stays just below the 1/2 mark.
Dan.
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on March 28, 2006, 10:03:23 AM
well, after driving the car for a couple of days now, it's evident that I have a leak.  It's on the drivers side near the expansion tank somewhere.  Here are a list of everything it could possibly be:
1)  the cap
2)  the bleed screw
3)  the drain valve
4)  the hose that conects to the radiator on the bottom on that side

What I've done already:  I made sure and retightened the drain valve, and I took the lower hose, made sure it was on good, and retightened the hose clamp.  Leak still exists.  Suggestions?
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on March 28, 2006, 05:39:05 PM
I may have found my leak.  Just for the heck of it, I took out the bleed screw.  I didn't even realize it was there, but there is an o-ring there that I hadn't put back properly.  I'm going to wait and test drive it to PT tomorrow morning. (0430 hrs.)  I'm sure everyone will be up early awating my results! :)
Title: DIY Thermostat and Coolant Replacement
Post by: ak96ss on March 28, 2006, 05:50:29 PM
Man, you guys do PT late...  must be a Navy thing...   :)

j/k

Go Army!
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on March 29, 2006, 08:03:41 AM
still leaking...
Title: DIY Thermostat and Coolant Replacement
Post by: Zoso on March 29, 2006, 08:05:19 AM
That sucks.  

Can you see any cracks along the plastic neck of the radiator?  I know they are known to break in the E36 world.
Title: DIY Thermostat and Coolant Replacement
Post by: ak96ss on March 29, 2006, 08:14:14 AM
What about putting the car up on ramps, letting it run, and getting under it to see where it may be leaking?

I seem to recall reading somewhere that there have been problems where the expansion tank joins to the core, as well.  How old is the radiator?
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on March 29, 2006, 10:27:13 AM
I'm guessing the radiator is origional, so that would be sixteen years.  To be honest, a crack is what I am afraid of.  I may have stressed it just enough by taking it out.  My next step is going to be to get underneath and look while it's running, as ak96ss said.  If I still can't figure out for sure, I'll probably take it to my mechanic to have a look.
Thanks for all the suggestions so far.
Brian
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on March 31, 2006, 08:23:23 PM
Well, after looking at it some more, It's evident that the leak is coming directly from the radiator.  So, what once was a simple thermostat change has escalated into a complete coolant system overhaul, now that I'll be replacing both the fan clutch and the radiator.

So, this brings me to another question.  Since I'm already going to be removing the radiator and fan clutch again, should I go ahead and replace the water pump at the same time?

Also, I may have a line on a used radiator on ebay, but if anyone has an extra one laying around (known good, of course), shoot me an offer and I'll see what I can do.
TIA
Brian
Title: DIY Thermostat and Coolant Replacement
Post by: ak96ss on March 31, 2006, 10:05:49 PM
I would a) replace the water pump, and 2) investigate the cost of a new core.  I don't know that swapping in a radiator of unknown provenance is worth the effort.
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on April 01, 2006, 07:28:32 AM
I hear what you're saying.  Better to do it right the first time.  While I'm in there I'll probably replace all of the hoses as well.  BMA has reasonable prices on all of that stuff, so I guess that's where it'll be coming from.
Thanks
Brian
Title: DIY Thermostat and Coolant Replacement
Post by: m42 fan on April 23, 2006, 01:58:07 PM
OK, Finally got this done today.  I have not had a chance to drive the car far yet, but so far, it does not look like it's leaking.  A couple of notes from the job:

1)  When removing the fan clutch, wedge a screwdriver between one of the bolts and the thermostat housing, that'll hold everything steady so you can get the nut loose.

2)  I was afraid of having extreme dificulty removing the water pump, as some on here have had.  When I was screwing the two M6 bolts in, one of them snapped the flange.  I slowed down, and tapped on the wp with a hammer every turn or so on the remaining bolt.  The pump came out fine from there.  Whew!

3)  Everything went back together real easy.  I started the car up to check for leaks and such.  Didn't find any really obvious ones.  the temprature gauge went to a tick below half and stayed there.  Excellent.

Problem:  it looks like I now don't have any heat in the car.  I was idling the car with the heat on full, and only cool air was coming out.  I'm guessing I screwed up bleeding the system or something.  Any suggestions?  Edit:  Took the car for a drive, I've got heat.  Don't know what was up with it earlier.

Brian
Title: DIY Thermostat and Coolant Replacement
Post by: 2002maniac on April 23, 2006, 08:36:12 PM
mine was leaking from that same are.  I thought it was a cracked hose so I grabbed the upper hose and gave it a good wiggle.  The inlet neck broke off showering hot coolant all over my arm and face.  

2nd degree burns are not cool.  Luckily there was no scarring.
Title: DIY Thermostat and Coolant Replacement
Post by: 318iEnthusiast on April 30, 2006, 10:16:39 PM
mine as been running at about 3/4 temp on the gauge...any idea on that?
Title: DIY Thermostat and Coolant Replacement
Post by: Zoso on May 01, 2006, 08:10:16 PM
Quote from: 318iEnthusiast
mine as been running at about 3/4 temp on the gauge...any idea on that?


I'd try replacing the thermostat - make sure it's the right temp one - and replace the coolant.
Title: DIY Thermostat and Coolant Replacement
Post by: KenC on November 28, 2007, 06:29:45 PM
Are these articles hosted anywhere else?
Title: DIY Thermostat and Coolant Replacement
Post by: mmason on January 06, 2008, 02:28:45 PM
Does anyone have a procedure that is for bleeding the air from the coolant system?
Title: DIY Thermostat and Coolant Replacement
Post by: hoevesruperd on January 06, 2008, 03:18:17 PM
when the engine's not running
open the bleeder valve on top of the radiator.(entlüftung) this plastic screw is worth 8$ at a bmw dealer so make sure you dont break it while removing it (4 months after i still have issues with coolant pissing on my straps)
add coolant until there is no more air bubble coming out of the bleeder valve. this might take a liter or 2 of coolant.
screw back the entlüftung screw
run the engine and see if you have to adjust the coolant level or if there is still air in the system. do the procedure over again if needed

this is how i remember doing it
i might be wrong on some points, if so, hopefully someone can correct me
Title: DIY Thermostat and Coolant Replacement
Post by: messerschmitt on October 06, 2009, 12:05:22 AM
I have been planing to flush the coolant yet Zoso's link no longer work. is there another link?
Title: DIY Thermostat and Coolant Replacement
Post by: Brian318is on December 21, 2010, 09:02:12 PM
Don't mean to bring up the dead, but this link is no longer working. Unfortunately, it seems Zoso's whole website is 404ing.

It was a great resource, and I've used it more than once for a DIY. Does anyone have a different host for these? I've tried viewing the cached pages, but there are no images.
Title: DIY Thermostat and Coolant Replacement
Post by: DesktopDave on December 22, 2010, 10:51:48 AM
I'll see what I can do.  I'll let you know if I can retrieve & post these articles.