Coolant Leak at Oil Filter Housing Console

Talk and Tech about turbocharged 924/944/968 cars
cda951
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Nice work, Tom. A good borescope is invaluable in this line of work, I use one several times a day on average.

I was about to remark that it is highly unusual for a peripheral head gasket coolant seal to suddenly begin pissing out coolant. Such a leak is usually a slow leak indicated by a buildup of crusty anti-freeze in the area of the leak. Anything sudden will be a combustion-related issue and will leak into a cylinder or two.
Chris A.
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Tom
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cda951 wrote: Fri Dec 26, 2025 1:29 pm Nice work, Tom. A good borescope is invaluable in this line of work, I use one several times a day on average.

I was about to remark that it is highly unusual for a peripheral head gasket coolant seal to suddenly begin pissing out coolant. Such a leak is usually a slow leak indicated by a buildup of crusty anti-freeze in the area of the leak. Anything sudden will be a combustion-related issue and will leak into a cylinder or two.
I need to get a better scope. The one I have was $25 on amazon. Huge bang for your buck, but I'd love to have one where you can aim the camera once it's positioned. I've never actually seen an oil filter console spring leak like this either, but the nature of the gasket makes it seem more likely than the HG anyway. Either way, I saw it with my own eyes, so will be digging in shortly...

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t36
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Oh wow. When i got my car it was leaking in the same spot. Worst part of that job for me was the oil lines - Crows foot sockets were essential for me ha ha.

#23

ROB III
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@Tom
Great video and appreciate your thought process for process of elimination and subsequent identification.
I also always like to 'see' whatever I'm diagnosing, even when tracking down a squeak or unwanted sound. Hearing a sound often gives general location, but looking at the area when the sound emanates was always the final action to identify the culprit. My logic is triangulation of ears and eyes.
Thank you for sharing.
Rob
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Thom
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Well done, good to hear it was not yet again another sealing issue between the block and the head.
'90 944 turbo

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Tom
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This is why it takes me so long to fix anything... As I worked to get to the oil filter console, I was horrified to see rust on this little bracket that holds the brake sensor wire clip up where the sway bar bracket mounts. So ended up blasting and powder coating both sides. So satisfying :wtf:

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dr bob
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I think just about every little car task I take on ends up with a list of other little tasks on the way in and again on the way out. Sometimes the 'other little' tasks dwarf the effort for the original 'every little task'.

E.G.: As I put the car up on tall stands for storage a few weeks ago, I decided to go after a small gearbox drip that only shows up on the floor after a few months of winter resting. It isn't anything I thought it might be, at least so far. But in that same 'so far', the gearbox is lickin' clean, and since some of that 'clean' leaked out to the immediately adjacent tub, the rest will need the same...

----

I may need one of those special "rabbit hole" borescopes. The one that has the little shutters and a fisheye lens, so it maintains focus on only the symptom I happen to be searching for in that moment.
dr bob

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ROB III
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Little tasks are the Black Hole of time and energy when dealing with older cars.
Rob
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PSU_Crash
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Tom wrote: Mon Dec 29, 2025 7:24 am This is why it takes me so long to fix anything... As I worked to get to the oil filter console, I was horrified to see rust on this little bracket that holds the brake sensor wire clip up where the sway bar bracket mounts. So ended up blasting and powder coating both sides. So satisfying :wtf:
This is a prime example of why the "paint job" on my Starion took 5 years :lol:
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Tom
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PSU_Crash wrote: Tue Dec 30, 2025 5:07 pm
Tom wrote: Mon Dec 29, 2025 7:24 am This is why it takes me so long to fix anything... As I worked to get to the oil filter console, I was horrified to see rust on this little bracket that holds the brake sensor wire clip up where the sway bar bracket mounts. So ended up blasting and powder coating both sides. So satisfying :wtf:
This is a prime example of why the "paint job" on my Starion took 5 years :lol:
I need to fight the urge to make this a 5 year oil-seal job. :lol: Today I killed an hour printing rubber seals for the various disconnected oil and PS lines. There was a time in my life when I'd fight through stuff dripping in my hair but, curiously, the less time I have left on earth, the more time I feel like I have to do things like this. I get a weird sense of satisfaction knowing how badly it wants to drip on me...but can't....

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