GL350 OM642 Oil Cooler Leak
#26
Long lasting fix for the oil cooler
There's no "longer last seal" for this design honestly. The problem arised when MB implemented the "modular design" that restricted the engine size and shape, so engineers had to put the oil cooler in such a weird position. Older MB engines put the oil cooler next to the oil filter on the outside that's so easy to replace. Older oil coolers were also known to fail and cause oil/coolant mix. The Viton seals are actually long lasting but some of them still fail within 100k miles. The temperature associated with the area is just too high.
#27
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2014 GL450, 1992 W140 300SD, 1993 W140 300SE, 1987 E30 Convertible
You can use this one instead of black silicon bs https://www.reinz-industrial.com/en/products/sealing-compounds/reinzoplast.aspx
#28
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'21 AMG53 wDPP & ARC, 19 GLC300 - Former- 10&14 ML BlueTecs, 20 GLE450 E-ABC, 15 Cayenne D, 17 Macan
You can use this one instead of black silicon bs https://www.reinz-industrial.com/en/...inzoplast.aspx
I didn't know that Reinz was part of DANA now.
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2014 GL450, 1992 W140 300SD, 1993 W140 300SE, 1987 E30 Convertible
The one I listed is not a gasket maker. It is polyurethane sealant which will sustain oil vibration temp and etc. As a matter of fact you might have a problem removing oil cooler later on because of its tough properties...
#30
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FWIW a few months ago I did the cooler seal replacement on our 08 E320 Bluetec. As a DIY job, it really isn't that bad. It's a bunch of hours i.e. it took me all day Saturday and Sunday to complete it. Plus I did a bunch of good WYIT stuff like replacing the water pump, the swirl flap motor, and cleaned the gunk out of the manifolds. No odd special tools needed, just a quality set of E-torx sockets, some regular sockets, and some various extensions and wobbles, and a 3/8" torque wrench. I estimate I spent ~20 hours including the extra WYIT stuff and that's going slow as I've never done this job before. As a DIY, it's a 10/10 in terms of time required, but for technical difficulty maybe only 3/10. Probably not a job for everybody, but if you're a competent DIY'er with a garage and tools, it's a reasonable weekend project. No need for a lift as everything is performed from above.
As for doing the job on an SUV, I can tell right away looking at our x166 Bluetec that the height will be an annoyance, as you must be leaning over the engine for much of the work, so a step-stool of some sort is needed. Also the turbo on the x166 seems tucked back under where the windshield wipers are. Not sure how you get back in there. Disassemble and remove the wiper motor / linkages / panels? Kind of funny that a mid-sized sedan like the E-class has better accessibility and more working room than a large SUV.
RE: using a sealant or gasket maker product, I would NOT use any kind of silicone RTV type product. It will squeeze out and get into the oil passages when you torque down the cooler. As a sealant that hardens, you'll at a minimum block your oil pump pickup screen with silicone pieces, and at worst, you'll clog an oil passage for bearing lubrication or piston cooling and destroy the engine. The only possibly appropriate sealant product here is a non-hardening (non-curing) type like that "Reinzoplast", if you use one at all. I installed the new purple oil cooler seals dry on our E320 Bluetec, and there is zero leakage now.
As for doing the job on an SUV, I can tell right away looking at our x166 Bluetec that the height will be an annoyance, as you must be leaning over the engine for much of the work, so a step-stool of some sort is needed. Also the turbo on the x166 seems tucked back under where the windshield wipers are. Not sure how you get back in there. Disassemble and remove the wiper motor / linkages / panels? Kind of funny that a mid-sized sedan like the E-class has better accessibility and more working room than a large SUV.
RE: using a sealant or gasket maker product, I would NOT use any kind of silicone RTV type product. It will squeeze out and get into the oil passages when you torque down the cooler. As a sealant that hardens, you'll at a minimum block your oil pump pickup screen with silicone pieces, and at worst, you'll clog an oil passage for bearing lubrication or piston cooling and destroy the engine. The only possibly appropriate sealant product here is a non-hardening (non-curing) type like that "Reinzoplast", if you use one at all. I installed the new purple oil cooler seals dry on our E320 Bluetec, and there is zero leakage now.
Last edited by argon3030; 05-04-2021 at 09:42 AM.
#31
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'21 AMG53 wDPP & ARC, 19 GLC300 - Former- 10&14 ML BlueTecs, 20 GLE450 E-ABC, 15 Cayenne D, 17 Macan
>snip>
RE: using a sealant or gasket maker product, I would NOT use any kind of silicone RTV type product. It will squeeze out and get into the oil passages when you torque down the cooler. As a sealant that hardens, you'll at a minimum block your oil pump pickup screen with silicone pieces, and at worst, you'll clog an oil passage for bearing lubrication or piston cooling and destroy the engine. The only possibly appropriate sealant product here is a non-hardening (non-curing) type like that "Reinzoplast", if you use one at all. I installed the new purple oil cooler seals dry on our E320 Bluetec, and there is zero leakage now.
RE: using a sealant or gasket maker product, I would NOT use any kind of silicone RTV type product. It will squeeze out and get into the oil passages when you torque down the cooler. As a sealant that hardens, you'll at a minimum block your oil pump pickup screen with silicone pieces, and at worst, you'll clog an oil passage for bearing lubrication or piston cooling and destroy the engine. The only possibly appropriate sealant product here is a non-hardening (non-curing) type like that "Reinzoplast", if you use one at all. I installed the new purple oil cooler seals dry on our E320 Bluetec, and there is zero leakage now.
The only time, ever, to use a sealer like the Reinzoplast or Permatex Gasket Maker (not RTV) is if you can't get the correct gasket. Squeeze-out is chancy.