Vanishing coolant discovered

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REman
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Vanishing coolant discovered

Post by REman » Thu Nov 14, 2019 4:04 pm

Hello,

Just discovered today the mystery to my vanishing coolant. Checked the floor of the drivers side and realized coolant soaked carpet at gas pedal , first thinking it was the dreaded heater water valve but that was totally dry to touch. Couldn't see any other area where it was coming from so I turned the engine on and let it get to operating temp and turned off, place a clean shop rag under the area and waited a while until I saw the drip coming from the back of the heater near the firewall. After searching Real OEM found this gasket back there...

https://www.realoem.com/bmw/enUS/showpa ... Id=64_0238

Anybody have any experience replacing this $3 part or is it going to be the PITA I think it is?

Thanks in advance, always grateful for all the help have received here for many years!!

Ivan
'81 528i... mfg date 10/80...owned 20 yrs +

canada karl
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Re: Vanishing coolant discovered

Post by canada karl » Fri Nov 15, 2019 9:55 am

What is the REaloem gasket part number you are referring to?
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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REman
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Re: Vanishing coolant discovered

Post by REman » Fri Nov 15, 2019 2:11 pm

Sorry it is the #6... 64111365809.
'81 528i... mfg date 10/80...owned 20 yrs +

canada karl
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Re: Vanishing coolant discovered

Post by canada karl » Sat Nov 16, 2019 10:01 am

It looks like a PITA to get at. You might have to pull the entire unit? The gasket appears to be N/A. Looks like a thick and odd shaped gasket that you might have to fabricate? Better set aside aside a few days to do that repair.
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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maybeillbuyit
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Re: Vanishing coolant discovered

Post by maybeillbuyit » Sat Nov 16, 2019 12:56 pm

I dont think #6 is going to be a part that is causing a leak. Its called a gasket but it looks to me its a piece of foam padding that the inlet and outlet water pipes go through the firewall to get to and from the engine to the heater core. When I changed all my coolant hoses I had a leak similar to the one you had. Coolant was dripping down the firewall into the driver footwell. Lucky for me it wasn't going under the carpet as I wouldn't have known for a long time. It turned out I hadn't tightened one of the coolant hoses enough. Check those to see if they are secure. Hose 1 or 2 . I think gasket #6 is just foam to help seal the passenger cabin from engine bay air.



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1977 530i another project
1979 635csi Euro "project"
1987 635csi

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REman
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Re: Vanishing coolant discovered

Post by REman » Sun Nov 17, 2019 9:44 am

Now that you say that, it did feel like a foam gasket and really doesn't make sense that it could seal water under pressure. I will need to check further to see where the leak is coming from, thanks.
'81 528i... mfg date 10/80...owned 20 yrs +

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maybeillbuyit
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Re: Vanishing coolant discovered

Post by maybeillbuyit » Sun Nov 17, 2019 5:13 pm

No problem, I did have a pic posted of the realoem schematic of the two coolant hoses that go in and out in the engine bay to help you but it doesn't seem to have worked. Good luck with that hopefully its just a loose clamp.
1977 530i another project
1979 635csi Euro "project"
1987 635csi

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REman
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Re: Vanishing coolant discovered

Post by REman » Wed Dec 04, 2019 8:43 pm

So decided it had to be the heater core after replacing the lower heater hose and monitoring the leak.
The picture below pretty much confirms after the deep dive of taking out the center council, evaporator housing, glove compartment and ultimately the heater housing to get to the heater core. What a nightmare of nuts and bolts!! Labeled most so I hope I can put back together right LOL!

Image

Image
'81 528i... mfg date 10/80...owned 20 yrs +

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maybeillbuyit
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Re: Vanishing coolant discovered

Post by maybeillbuyit » Wed Dec 04, 2019 10:51 pm

I can't see your pics but I feel your pain. I've been partway into that center console area and it a maze of stuff. Good luck. Taking pics helps for sure
1977 530i another project
1979 635csi Euro "project"
1987 635csi

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