[fastboatster]

Are there any? broke my radiator's upper hose fitting trying to get the upper hose off, in a hindsight, should have just cut the upper hose fitting with dremel. Can I use a radiator from an auto trans car?

[fastboatster]

update: oreilley's seems to have something:
https://www.oreillyauto.com/detail/b...radiator&pos=1

[fastboatster]

looking more into this, looks like somebody suggested using csf 3718 and either swapping over your own sensor or repinning some mercedes sensor.

[Serf27]

I swapped over my own sensor when I replaced the radiator and it worked.

[fastboatster]

Originally Posted by Serf27

I swapped over my own sensor when I replaced the radiator and it worked.

Sounds great, I would really appreciate more details. Which radiator did you get (was it for an auto or a manual?) and how did you remove the EAC sensor, I believe it's superglued to the radiator.

[Serf27]

I don’t remember what radiator it was, used OEM I think. It was for an auto.
I used a grinder to cut around the sensor carefully then plugged the sensor in and tucked it away.

If you cut the sensor with the grinder it won’t work. Has to only be cut on the outside.

[fastboatster]

I see. Looks like to get this to work, I’ll need a new radiator, new sensor from the Mercedes which I’ll have to repin to use e90’s connector housing and loctite 4204. Will be cheaper, but a lot of moving parts

[Serf27]

At the time I cut the sensor out and used a regular radiator, the only option for that radiator cost about $350?
If I knew o Riley’s had it for $200, I would’ve paid $200 for it.

[fastboatster]

Well, OEM radiator is about 500 to 600 nowdays. While I wouldn’t mind spending 500$ on my car, there’s no reason if it can be done for less

[fastboatster]

Hmm, most of the vendors have a core charge for an mb ozone sensor and it’s quite steep ~500$

[fastboatster]

Anyway, found an eBay posting which doesn’t seem to have a core charge. Also decided to buy csf rad. If I mange to pull the old sensor from my old radiator, great, if not, will install the mb’s sensor. Btw, I spilled some oil on the belt, right at the very bottom where I can’t reach with my hands. What would you use to clean it up? I thought of removing it and washing with some dish soap. Would be great if I didn’t have to pull it out

[Serf27]

Why don’t you buy it from o Riley’s for $200?

For the belt just wipe it clean with a wet rag.

If you cut the sensor from your old radiator, cut around it. If you cut into the sensor a little bit it won’t work.
Cut the yellow squad out that I outlined in this photo and it should work.

[fastboatster]

Didn’t buy from Oreilley because that radiator has a port in the core for the sensor but it doesn’t come with one. So rather than spend 200 for the rad with no sensor, I bought a rad with sensor port, ordered mb’s sensor from the eBay with no core charge and bought some glue from the VW used in the same application. I think it’s slightly more than oreileys rad, mostly because of expedited shipping

[fastboatster]

Quick question- did you reglue your sensor? I figure the glue is there only to prevent the reuse, tabs are more than enough to hold it in place

[Serf27]

The picture I tried to upload did not work.

You cannot pry the sensor off the radiator, the entire sensor plus the portion of the radiator where it is glued onto must be cut out.

[fastboatster]

Oh, I understood that, I was asking if you glued the sensor to the new radiator.
Right now, i’m struggling with cooling fan connector removal and removal of radiator sensor connector housing from the radiator.
I can’t depress both locking tabs on the fan connector, can’t get my finger on the one next to the shroud

[Serf27]

No, I did not glue it to the new radiator, I just tucked it away. I forgot where I put it, maybe tucked behind the bumper?

The sensor connector on the radiator rotates and pops off, super easy.

As for the fan connector, use a flat head screw driver to pry up the bottom tab.

[fastboatster]

Yep, sensor connector popped right out when I rotated it. Tried to pull the fan connector again like some people on YouTube do, but there’s no way my fingers fit between the shroud and connector housing, will have to use a screwdriver as you suggested

[CTinline-six]

What exactly is the purpose of the sensor and how does it play into replacing the radiator? I ask this as an N51 owner who has not touched the radiator in mine yet.

[nsjames]

Originally Posted by CTinline-six

What exactly is the purpose of the sensor and how does it play into replacing the radiator? I ask this as an N51 owner who has not touched the radiator in mine yet.

makes sure your emissions required ozone coating is there

The N51 manual Genuine BMW radiator includes a special coating that converts ozone into oxygen. This coating helped BMW with California emissions certification and the coating is required for all replacement SULEV radiators. The radiator actually has a compliance sensor fused to the back of the radiator to ensure the coating is applied and active, as well as feeding coolant temperature information to the engine computer. A new sensor is included on this radiator. Using a non-SULEV radiator without the coating will trigger a fault code and check engine light. Unfortunately, the sensor is not available separately from BMW and is not easily removed without damaging it.

https://www.bimmerworld.com/Cooling/...E93-SULEV.html

[fastboatster]

In my understanding, it’s there as a way to make sure that you are running special n51 radiator in your sulev e90. That’s why it’s not available separately from the bmw and can’t be removed from the radiator easily. All it does is monitoring the temp inside the radiator core to make sure it’s consistent with temp readings from other sensors. If n51 dme gets an implausible signal, it will illuminate SES light and you won’t pass the smog. I haven’t seen anywhere if the input from this sensor is used for FI control, I think other manufacturers are more explicit on this sensor’s purpose and call it radiator identification sensor (VW)

[Serf27]

Yea try a screwdriver.

I’m not sure if it measures coolant temp. I think it just measures that you are using that radiator for emission purposes. I may be wrong, but.

When I cut mine off and used a regular radiator, the sensor would’ve obviously had a different temp reading than the actual temperature. It never triggered the SES light for me.