Philly98540, I've installed thermostat and it works well

[BMW540san]

I believe the picture says it all. It looks as combination of melting plastic (internal heater short?) and coolant seepage. I'm not saying this is going to happen on every 540, but it's worth to occasionally check the connector. Some are saying I'm just imagining things, but as far as I care, they can continue to keep head in the sand.
The last picture is from some other car and it's similar to mine. I guess that guy is imagining things too.
The 95 C mechanical thermostat was easy install and it kept temp at 95-97 C while idling after initial fill up / bleeding. So far no check engine light and the real test is tomorrow when I refill if needed and take it for a test ride.
[IMG][/IMG]

[JimLev]

Did you put a resistor in the circuit as a load so the DME thinks the heater is still connected?
I'm probably going to drill a few small hole in mine.

[BMW540san]

Did you put a resistor in the circuit as a load so the DME thinks the heater is still connected?
I'm probably going to drill a few small hole in mine.

I haven't done anything. I'll drive it today for a while and if it throws light or not, I'll hook up AE and see if there are stored codes. If check engine light comes on then I'll do as you suggested. I'll update some more later today. I think Stewart thermostats have drilled holes, so you're on the right path.

[philly98540]

540San- Perfect. Looks like an identical casting, just without the extra heater gizmo. I like this set-up much better than the aftermarket one I put in with the sandwiched gaskets.

As Jim said, did you put in a resistor? Get a CEL? I got a CEL until I added the dummy load on my 98'.

Did you trace the wire to the other end and check for glycol residue there?

Do some more driving and let me know how it holds temps during various conditions.

Mine works pretty good, and typically holds temp at 97-98 C, but it seems to have some stiction in it at times that causes the temp to go up to 102, then it drops back down without changing load or conditions. This can even happen when its cold out. I think I just got a bum one that sticks a little. I'm hoping this BMW unit you got may be a bit better built than the aftermarket one I put in.

Thanks for the pics and doing the leg work. I wonder if they make a 85 or 90 deg C unit of the same type construction?

[BMW540san]

540San- Perfect. Looks like an identical casting, just without the extra heater gizmo. I like this set-up much better than the aftermarket one I put in with the sandwiched gaskets.

As Jim said, did you put in a resistor? Get a CEL? I got a CEL until I added the dummy load on my 98'.

Did you trace the wire to the other end and check for glycol residue there?

Do some more driving and let me know how it holds temps during various conditions.

Mine works pretty good, and typically holds temp at 97-98 C, but it seems to have some stiction in it at times that causes the temp to go up to 102, then it drops back down without changing load or conditions. This can even happen when its cold out. I think I just got a bum one that sticks a little. I'm hoping this BMW unit you got may be a bit better built than the aftermarket one I put in.

Thanks for the pics and doing the leg work. I wonder if they make a 85 or 90 deg C unit of the same type construction?

As I told JimLev, I haven't put resistor or anything. The light may come on today while driving, we'll see. Last night I only did the initial run while stationary to get to the operating temp. Today, after driving it, I'll check for stored codes.
I didn't pay much attention to the other wiring end since I never got the check engine light and it looks ok other than tiny gasket in DME connector is showing signs of overheat which corresponds to the melting plastic on the thermostat end.
I scoured the realoem for "middle east edition" BMW with M62 engine in hoping for lower temp thermostat but no luck.
I'd hate for you to spend extra money and go my route since you just installed yours. You may get labeled as I did, paranoid and guy with no life. I stay up nights thinking of that.

[supra94tt]

The check engine should not come on as thermostat(map cooling) is not part of the "OBD readiness codes" system or the emission system(directly). It may set a fault code in DME for the map cooling, that's about it. Keep us posted. Im talking to a guy in Europe to get me the 88C thermostat for my car(direct fit-no heating element).

[philly98540]

The check engine should not come on as thermostat(map cooling) is not part of the "OBD readiness codes" system or the emission system(directly). It may set a fault code in DME for the map cooling, that's about it. Keep us posted. Im talking to a guy in Europe to get me the 88C thermostat for my car(direct fit-no heating element).

On my 98', it threw this code: 06-8B Electric thermostat control final stage.

Until I put the dummy load in place. Let us know if you find an 88C stat from Europe and post the part number. Thanks!

[supra94tt]

The part # is 11512248542, go here and enter it: http://www.carparts-pros.com/page_1_3.php#oeformo , that's the lowest price I found it for, I emailed the place to ask about shipping to US.
Other part #'s http://www.findpart.org/part/vem-v20990161

[BMW540san]

Jim, Chris, Supra94tt,

Done about 50 miles today, ambient temp 70-80 F, run car through hills anywhere from 3-5k rpm , flat, interstate, a/c on, a/c off. No check engine light, not either fault in DME, unless my AE is not able to read it. I'm surprised by no code, but even better.

Mostly running at 95-98 C, up to 101 C sitting at light with a/c on. I expected for temp to fluctuate more since no DME in play to open thermostat early while under load, but not so. I could not be happier.
$88 and 2 hours of work was worth it in my book.
Direct fit to M62 and if only difference for M62TU is hose design that's easily resolved. Remove the end of the hose toward the thermostat housing, cut about few inches, use something like this adapter in the link and then use piece of M62 hose to connect to the other end adapter and the other toward the thermostat housing.
http://www.summitracing.com/parts/tf...cool/overview/

[philly98540]

The part # is 11512248542, go here and enter it: http://www.carparts-pros.com/page_1_3.php#oeformo , that's the lowest price I found it for, I emailed the place to ask about shipping to US.
Other part #'s http://www.findpart.org/part/vem-v20990161

Looks like it is designed for a quick connect hose and not clamped hoses, and the angle is different. Likely needs some hose mods and special end to mate to pre TU cars. Temp looks good though. May fit TU cars as is. So, nice find, but not ideal for my car. Thanks for sharing.

- - - Updated - - -

Jim, Chris, Supra94tt,

Done about 50 miles today, ambient temp 70-80 F, run car through hills anywhere from 3-5k rpm , flat, interstate, a/c on, a/c off. No check engine light, not either fault in DME, unless my AE is not able to read it. I'm surprised by no code, but even better.

Mostly running at 95-98 C, up to 101 C sitting at light with a/c on. I expected for temp to fluctuate more since no DME in play to open thermostat early while under load, but not so. I could not be happier.
$88 and 2 hours of work was worth it in my book.

Sounds like its working good. I think I got the code on my second long drive, let us know if yours throws one. Maybe my car has different coding? Nice direct fit up for the non-TU 540's. Good find.

Maybe our second set of chain guides may last an additional few miles with lower temps.

I sure would like to find a 85 deg direct fit for my car...

[supra94tt]

Looks like it is designed for a quick connect hose and not clamped hoses, and the angle is different. Likely needs some hose mods and special end to mate to pre TU cars. Temp looks good though. May fit TU cars as is. So, nice find, but not ideal for my car. Thanks for sharing.

Yea, this is a direct fit for M62-TU engines only.

[Alpina540i]

Yeah I told supra about that vemo thermostat a few weeks ago.

I placed an order for one from Germany a week ago and its just arrived in the states so I will have it in a few days to install on my TU engine.

I will post an update when I install it if a few days.

-Anson

[AK_5eries]

So 540san, the correct part number for non vanos M62 95C thermo is: 11531745476?

[rf900rkw]

101C with a 95C thermostat is not "working well".

[Alpina540i]

Well it seems like the stock M62TU opening is at 105 C and my engine routinely gets to 109C when not moving. All new cooling system as you know.

So a 4-5 C difference from the opening temp when not moving seems to be the norm.

[rf900rkw]

The M62TU stock setting is 108. Since the system is reactive, 109 is expected, but not 114. And I'm not saying the problem is the new thermostat. But 6C over setpoint at no load low ambient and the electric fan on due to the A/C is less than proper.

[philly98540]

The M62TU stock setting is 108. Since the system is reactive, 109 is expected, but not 114. And I'm not saying the problem is the new thermostat. But 6C over setpoint at no load low ambient and the electric fan on due to the A/C is less than proper.

Why so? Its just a valve modulating to temp. At lower rpm and thus less water pump output the temp has to go up some. The stat has a given opening amount for every degree. Is 5 deg rise too much in your mind? If so why? Not a big deal in my book but to each his own.

[supra94tt]

The stock TU thermostat is rated at 105C, it is stamped on it, I too see temps around 106C-109C, I'd say 90% of the time it's at 109C while driving on highway. (Evans Fluid.)

- - - Updated - - -

Yeah I told supra about that vemo thermostat a few weeks ago.

I placed an order for one from Germany a week ago and its just arrived in the states so I will have it in a few days to install on my TU engine.

I will post an update when I install it if a few days.

-Anson

Yes , I have to give props and credit to Alpina540i for all the info about the TU thermostat , thanks again .

[JimLev]

My spare t-stat (tu engine) is stamped 105C.
The heater on mine has a clip just the the tu hose ends have. When I get back home I'll pull the clip and see if the heater comes out. If you want to put a resistor in its place mine read 11.2 ohms. If you can fine a 12 ohm 25 watt resistor that should work fine.
88C is a little low for me, I'd like it just below boiling. Will try to drill a few small holes in my spare one.

If you can't find a 12 ohm resistor a 15 ohm should work fine.
I pulled the clip out but the heater wouldn't budge, didn't want to break it so I put the clip back in.
I've drilled one 1/8" hole in the t-stat, I'll install it this winter.

[supra94tt]

My spare t-stat (tu engine) is stamped 105C.
The heater on mine has a clip just the the tu hose ends have. When I get back home I'll pull the clip and see if the heater comes out. If you want to put a resistor in its place mine read 11.2 ohms. If you can fine a 12 ohm 25 watt resistor that should work fine.
88C is a little low for me, I'd like it just below boiling. Will try to drill a few small holes in my spare one.

I also thought about drilling holes(one by one) in mine, lol, and see if it makes a diff. and how much. Judging the way the stock one works, I expect to see temps around 92C with the 88C one, look at the temp of the E39 M5 thermostat 79C . I actually have seen the stock thermostat drop the temps to about 93C in heavy stop and go traffic numerous times, and it kept it there for a while(10-15min?).

[Alpina540i]

Perhaps I'm mistaken Randy. I have read so many posts about different thermostats.

Either way can't wait to bring my temps down.

I agree Supra seems like with the 88 C stat temps will be around 92-93 C or just under 200 degrees F

[AK_5eries]

The M5 thermo is 79C?? Or is that a typo?

[Alpina540i]

Thats correct

[AK_5eries]

Any reason why there is such a huge difference between the M62 and S62 operating temps?

[philly98540]

Any reason why there is such a huge difference between the M62 and S62 operating temps?

Performance vs Efficiency