Thermostat for EGR cooling

[JENICH]

Hey there guys,
The thermostat for the EGR cooling in my E90 has sprung a leak, and judging from the picture below, it just needs an O-ring which I will get from BMW for R10.

Now where item 10 fits into item 11 is where the o ring fits.

My question here is,
Is it as simple to unscrew the 2 bolts to separate the 2 pieces and replace the o-ring then screw back.

Should I park the car outside as apposed to doing it in the garage, done want water flowing all over the place

Thanks guys

 

[Waseem 333i]

That set up looks the same as the e46.

Some water will come out but no lot. Maybe half a litre or so. Perhaps consider getting a bleed screw just for a back up. I recently fiddled with all the bleed screws on my car and after a week one gave way. You will need to open that bleed screw on the thermostat when topping up the coolant after you replace the o ring.

It is as easy as just removing the two screws but on my e46 a had to remove the vacuum line to get to the other screw. Easy easy job.

 

[Nikhil]

Remove, new oring, bleed and you sorted. 500ml coolant is to much but good to have extra. Do it outside.

 

[Solo Man]

See AndyGP's recent diy about replacing the egr thermostat to see how easy it really is.

 

[JENICH]

Thanks guys for all the help but need some more help.
I removed the egr and this is what i found.

So once the new o-ring was fitted and bled everything, i saw something lying at the bottom on the tray.

Can anyone tell me what this is.
My car is a 2005 E90 320d.

Thanks guys

 

[Nikhil]

That looks like it fell out from inside the egr? Apart from that are you running coolant or water? That looks like alot of rust buildup.

 

[JENICH]

Hope not.
Because it put everything back

 

[Solo Man]

I also think it is the inside of the egr, in other words it is the thermostat part of the plastic fitting. Must say, when i replaced the egr thermostat on my 2006 E60 530d recently it looked nothing like that picture, it was clean looked almost like new. Seems as if your car had no anti freeze in for quite a while.

 

[JENICH]

Looks terrible.
Gonna get anti-freeze tomorrow and do a radiator flush.
Will the flush sort that brown crappy stuff out?
Here is a pic of the inside

So opened it up again and fitted that part back in.

So rattled by what i saw.
Whats the worst that could happen in this instance guys and will that radiator flush sort this out.
Regards
Jerry

 

[Nikhil]

Ok so this is my process everyone has there own method, drain the cooling system from the radiator completely, buy a 5l coolant and distilled water from midas, fill the system and bleed it, run it like that for a week make sure you use the heater as well. Following weekend throw in some radiator flush and then drain. If the water is clean then fillup bmw coolant and distilled water mix. If its still dirty repeat the process With the midas coolant. Its a pain and takes quite a bit of time and effort but i find it to be the best method to remove all the crap in the cooling system.

 

[JENICH]

Thanks a mil Nikhil.
Just stressing about any damage this might have caused

 

[Andy1GP]

I take it you haven't replaced that thermostat yet? Just a seal isnt the solution imo. Both thermostats fail on these cars. Thats normal. Whats not normal is the fuel consumption and excessive piston ring wear that will ensue with both of them running wide open the whole time.

That piece that came out is part of the egr thermostat. Its the plunger that regulates the water bypass. You can run the car without it but again it wont allow the motor to get up to operating temp +-88 deg C.

Spannie on the forum bought his egr thermostat for like R450 bucks. Its a no brainer imo. Followed by fluid flush like Nikhil said. Theres rust forming from lack of antifreeze.

Hope this makes sense. Good luck :thumbs:

 

[JENICH]

I take it you haven't replaced that thermostat yet? Just a seal isnt the solution imo. Both thermostats fail on these cars. Thats normal. Whats not normal is the fuel consumption and excessive piston ring wear that will ensue with both of them running wide open the whole time.

That piece that came out is part of the egr thermostat. Its the plunger that regulates the water bypass. You can run the car without it but again it wont allow the motor to get up to operating temp +-88 deg C.

Spannie on the forum bought his egr thermostat for like R450 bucks. Its a no brainer imo. Followed by fluid flush like Nikhil said. Theres rust forming from lack of antifreeze.

Hope this makes sense. Good luck :thumbs:

Thanks for the explanation bud,
Looks like there was no anti-freeze at all in the car,
I replaced that "shaft" and put everything back,
Left home around 06h30 this morning when it was still cool and operating temperature got up to 90 deg max in stop go traffic, which I don't see as that bad.

What I did see when I arrived at work was some condensation on the bonnet on the same side as the water reservoir.
So opened the bonnet and looks like water boiling and spitting out from either the cap or the bleeder screw.
Maybe there is still some bubbles in the system.
Gonna let it cool and maybe bleed it again

Does this make sense guys
Gonna have to get a new part

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So this bleeder screw broke

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JSN wants R145 for this screw:YesNo::YesNo:

 

[sash]

Crap Jerry , sorry to hear of your troubles.

The rust issue in the cooling system can become quite serious. Over time the build up can hamper the flow of coolant through the radiator and eventually reduce the cooling effect. It wont be noticeable at first but if you are in a situation where you are stuck in traffic for a while there wont be enough flow of cooler fluid through the system and the system slowly overheats.

While not one BMW my dads toyota had no coolant in it for the longest time and he ended up with the problem mentioned above. Ended up replacing radiator, pipes, water pump, welsh plugs, thermostat.....

Clean it ASAP.

 

[JENICH]

Hey there Sash,
I hear you bud,

Getting the anti-freeze today as well at that bleed screw, Gonna run it for a week and flush it out.

Thanks bud

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BTW,
Guys, who knows what the normal operating temperatures on these vehicles supposed to be?

 

[sash]

90 degrees
but give or take a few degrees, so 88-92

 

[Waseem 333i]

I told you about that bleed screws. Its around R67 give or take. R143 is too much.

 

[Solo Man]

Your new egr thermostat will have a new bleed screw.