88°C thermostat thoughts

[jicaino]

Hey guys

Given the awesome wrenching skills on the average guy here, I'm surprised that no one thought about these options for the 88°C thermostat

A) transplanting the actual thermostat into a good case with a working heater element
B) transplanting the heater element into the new 88°C case, since the heater element port is very basically plugged with a turned aluminum cap, fitted with an O-ring and held into heater element place by the same clip that holds down the connector.


Now that I have a couple of spare units on the bench, they come appart pretty easily, and the thermostat is a match for all M6x engines, the only thing that changes is the casing (bolt pattern, hose clamp or quick connect styles)

If you were inclined to decide your operating temp range, the only thing you need to remove the actual thermostat from the casing is some water pump pliers, or 2x 10"x.75"x.25" aluminum bars and a hacksaw if you want to make a "wrench".

[JimLev]

The heater on my 108 t-stat isn't removable. I've taken the clip out but it refuses to come out.

[gmak]

How did you remove the working heater element from the old thermostat? Could you take pictures and post a DIY? When I tried on an old one, the plastic didn't survive.

I've documented my adventure of the 105C -> 88C switch here. If you look at 3 or 4 posts following the first, you can also see where I took apart the 105C thermostat.

[AK_5eries]

Interested in this also.

So just to confirm, can the M62 thermostat be removed from the housing it comes in?

Gmak just a point of clarification.
M62 non tu 105c thermo
M62tu 108c thermo

[jicaino]

All of the V8 thermostats can be removed from the casing and fits the newer/older casings. If your heater element is fine and throws no codes or leaks you could remove the thermostat from the assembly and install it in your casing, making selecting the operating temp range just a matter of personal preference.

The only reason I could think that wouldn't make this a great idea is the known/reported issue of the sender leaking coolant into the wiring loom back to the DME box.

Then I thought about leaving the new 88°C alone and remove the heater element from the old casing and just leave it hanging around. The DME will not activate it because it will read a coolant temperature as if it were active already. No need to chop wires and install resistor, just hanging a functioning heater element will suffice.

I removed it using a combination of heating the casing with a butane torch and spraying WD40 while hot.

[AK_5eries]

Interesting. So it can be removed. So its not cast or welded in there? BC for example the spacer method to reduce operating temps calls for cutting the thermostat out of the housing. So I assumed it wasn't removable. Good to know.

[geargrinder]

Then I thought about leaving the new 88°C alone and remove the heater element from the old casing and just leave it hanging around. .

Ha ha Juan, I haven't put my 88 I'm yet but I have my old old factory unit and was intending to do (try I should say) exactly the same thing! I'll be checking that out soon. I do like the idea of using the 88 as-is solid w no hazard of the plug...

[jicaino]

Well, I've just f'd up the thermostat that I had installed in the car (the OE 105°C with heater element). Apparently the one I succeded in removing wasn't sealing properly. The one that was on my car (had '09 prod date) was perfect and when I tried to remove the heater element, I snapped off the connector leaving the heater behind into a very hard rosin encapsulation that seals the thing inside. No wonder why the one I could remove was leaking...

So to sum it up:

If you want to keep the pesky connector, you need to disassemble both the old and the new thermostat of your preferred temp range and put together one thermostat on your casing. This opens up the game being able to pick 105°C - 88°C - 85°C - 80°C as operating temps.
If you have a pre-TU with the old style hose and clamp neck and want to use the 88°C, you can get the new style 88°C and use the actual thermostat on your casing.
If you have a TU and want to go lower than 88°C you can get a 80°C or 85°C from the M60 and transplant the thermostat in your quick connect case.

After the ones I botched up removing the connectors, I don't think I'd want to use a OE with heater element. I left my 88°C as it came with the solid aluminum cap in lieu of the heater element, preferring to have less points of leaks to worry about. I don't have a CEL nor a code for the heater element. I don't think that the DME should ever activate MAP cooling reading 10° to 20°C less in coolant temperature... but will see after driving about 800 miles this weekend.

Drove in the city in heavy traffic, doing a lot of stop/go and really slow driving. The car would raise temperature to 115°C in that situation (no visco fan) The most I could read was 101°C. When it's moving it settles around 95/99°C. Will see in the road, I have to go out this weekend. For the time being I don't know why I didn't do this before, the car feels a lot less heat fatigued now, and has better power (like DME is pulling less timing)

[HoZy]

pre-TU can rock an 85c (11531742964), I've been running one for 2years now.

No point messing around making a "hybrid" t-stat with heater element which is useless seeing as the t-stat is a lower temp anyway.

No error EML from leaving unplugged just a code, which whoopdedoo.

[jicaino]

pre-TU can rock an 85c (11531742964), I've been running one for 2years now.

No point messing around making a "hybrid" t-stat with heater element which is useless seeing as the t-stat is a lower temp anyway.

No error EML from leaving unplugged just a code, which whoopdedoo.

Agree. Thanks for the 85°C tstat part number. As I stated, you could also run it in our newer TU cars. I will post picturesof the tools I've made for taking the tstat out of the casing, so you can run whatever temp you'd like on any car (T U or non vanos)

[philly98540]

I am running the same stat as Hozy. Works great. My car lit up CEL so I had to add the resistor. Some seem to throw a CEL and some not.

[jicaino]

Mine hasn't showed nothing, not even a code for the heater element.

[BMW540san]

Interesting, I also thought that you can't separate the thermostat from the housing. I'm glad I was able to sell out my batch of 88C thermostats (11 in total) before this info ruined my small side business, lol.

I still prefer 85C, 95C in pre Vanos form and 88C in Vanos form vs modifying the 105C thermostat and leaving DME electrical connector active.

As I posted some time ago and as shown in gmak post link video, DME connector can leak coolant which melts / shorts connector or in some rare case coolant travels up the wiring loom into DME and causing a havoc with electronics.

[jicaino]

Interesting, I also thought that you can't separate the thermostat from the housing. I'm glad I was able to sell out my batch of 88C thermostats (11 in total) before this info ruined my small side business, lol.

I still prefer 85C, 95C in pre Vanos form and 88C in Vanos form vs modifying the 105C thermostat and leaving DME electrical connector active.

As I posted some time ago and as shown in gmak post link video, DME connector can leak coolant which melts / shorts connector or in some rare case coolant travels up the wiring loom into DME and causing a havoc with electronics.

Hey! if anything I think it would have helped you move those tstats way more efficiently. Many people still ponders and wonders about the heater element thingy. If they can swap just the thermostat into the casing they'd have bought your thermo and used their casing...

But I agree, I didn't want to worry about the heater element leaking coolant into my DME so I left it out, just curled up the pigtail up under the engine cover. As stated, not only no CEL but no heater element open codes.

I will post a picture of how they can be removed out of the casing asap.

BTW maybe you can contact your supplier about the thermostat alone, without housing?

[geargrinder]

Interesting, I also thought that you can't separate the thermostat from the housing. I'm glad I was able to sell out my batch of 88C thermostats (11 in total) before this info ruined my small side business, lol.

I think actually this doesn't ruin that biz at all. A lot of TU guys will like the idea of having a sealed housing and the 88 being 'drop in' is great for that, no muss no fuss.

[BMW540san]

You're right, I misunderstood the point of post.

I think actually this doesn't ruin that biz at all. A lot of TU guys will like the idea of having a sealed housing and the 88 being 'drop in' is great for that, no muss no fuss.

- - - Updated - - -

You're right. I'll check if I can dig something up about the thermostat alone.

Hey! if anything I think it would have helped you move those tstats way more efficiently. Many people still ponders and wonders about the heater element thingy. If they can swap just the thermostat into the casing they'd have bought your thermo and used their casing...

But I agree, I didn't want to worry about the heater element leaking coolant into my DME so I left it out, just curled up the pigtail up under the engine cover. As stated, not only no CEL but no heater element open codes.

I will post a picture of how they can be removed out of the casing asap.

BTW maybe you can contact your supplier about the thermostat alone, without housing?

[valveFLOAT]

any other 88*C stat users beside that youtube poster (member here?) experience the added benefit of the reduction and/or elimination of the infamous vanos dieseling phenomena...?

[jicaino]

My car has no weird sounds or rattles so I wouldn't know. What I can say is that cooler engine means less timing being pulled off by the DME, and that rendered me a 10% increased fuel efficiency in the road. I expected to see reduced mileage (especially in the city) but it has been better on the road. Haven't driven much in the city yet.

[geargrinder]

I'd be really skeptical if it did anything for startup rattle if that's what you mean. My view is startup rattle is caused by drainback from sticking check valves and/or VANOS seals, and I don't see slightly cooler oil at shutdown making huge differences there.

Idling / consistent rattle? That's gonna be guides and it ain't gonna fix that.

It very well can be expected to extend your guide life though!

[jicaino]

I'd be really skeptical if it did anything for startup rattle if that's what you mean. My view is startup rattle is caused by drainback from sticking check valves and/or VANOS seals, and I don't see slightly cooler oil at shutdown making huge differences there.

Idling / consistent rattle? That's gonna be guides and it ain't gonna fix that.

It very well can be expected to extend your guide life though!

My thoughts exactly. Extended guides life, more than just probably. Curing already onset rattles and reverting damage, don't think so

[jicaino]

Here's how to replace the thermostat. You can remove the 105°C thermostat from the heater element type case and replace it with your choice of temp range. (80°C - 85°C - 88°C)

[jicaino]

I have my 88°C installed now so I can't take pictures of it. I don't think that the tstat can keep the heater element in place.
This is the heater element


Here's the whole assembly


And this is where it fits the mechanical thermostat

[AK_5eries]

Awesome. I know the difference is only 2C, but I'll throw it out there.

After extensive research, I'm almost 100% sure that we now have an OE 90C option for those that prefer that temperature thermostat.

The M73 V12 90C thermostat. Part number: 11531704704


Just remove the thermostat as shown by J in his video and swap onto your housing of choice.



FYI: A cheaper option for the 85C/95C thermostat is to buy the M60 thermostat housing (part number: 11531720173) [M70 housing will not work due to angle of outlet] + the 85C thermostat (part number: 11531729720) or the 95C thermostat (part number: 11531702279). Both of these thermostats were found on the M60 V8 and M70 V12. Total $40 instead of the $120 for the integrated housing option.

We now have four OE drop in options: 85C - 88C - 90C - 95C


I think there is also a 80C option, but not 100% sure.

[jicaino]

Awesome. I know the difference is only 2C, but I'll throw it out there.

After extensive research, I'm almost 100% sure that we now have an OE 90C option for those that prefer that temperature thermostat.

The M73 V12 90C thermostat. Part number: 11531704704


Just remove the thermostat as shown by J in his video and swap onto your housing of choice.



FYI: A cheaper option for the 85C/95C thermostat is to buy the M60 thermostat housing (part number: 11531720173) [M70 housing will not work due to angle of outlet] + the 85C thermostat (part number: 11531729720) or the 95C thermostat (part number: 11531702279). Both of these thermostats were found on the M60 V8 and M70 V12. Total $40 instead of the $120 for the integrated housing option.

We now have four OE drop in options: 85C - 88C - 90C - 95C


I think there is also a 80C option, but not 100% sure.

Great information!

[killian665]

Just heard about this for the first time. Where are you getting these 88C thermostats?