King James

Hi all!

Just in time for winter , I seem to have developed a coolant leak on the front of my Weissach. Looking for tips/pointers/BTDT's as I struggle to beat the winter freeze.

Here's what I can detail: When running and warm, coolant leak is visible running down the black plastic timing belt cover, roughly right down the middle, leaning a tad towards the drivers side. Also I have noticed a pool of coolant in a shallow depression behind the water pump assembly (on the block).

I've taken off the TB covers and now can see the pulleys/TB, etc...but no idea where the leak could be coming from?

Any help / suggestions will be much appreciated!!

jserio

James, Get yourself a pressure tester. It will be one of the best items you can get for your tool box. I litterally found my leak in 20 seconds.

heinrich

the leak is likely the seal under the thermostat housing. So, look at the top of the lower rad hose at the engine. That is the thermostat housing. follow it till it meets the block between the heads, there is likely your leak. seal costs nothing.

Big Dave

De ja vu. I had a similar leak. It turned out to be BOTH the thermostat housing seal and....the water pump itself. I was only able to tell it was the H20 pump, too, after fixing the thermostat seal.

bd0nalds0n

Pressure testers--are they a universal fit kind of cap thing that you pump? Available at somewhere like Napa (et al.)? Or is it specialized for the specific cap fitment?

jserio

I got mine from TOPS Auto. The cap it came with was just fine. Didn't seem like anything special. Because I was able to put the system under pressure without running the car made it easy to check hoses that were hidden without burning my hands.

adam928

BTDT..
In my case:
Same symptoms... water accumulating in that small pocket below the thermostat housing...

Cause:
Someone (PO?) had switched the hose clamps the lower water hose so that the lower och upper clamps where switched. The bigger one that is supposed to sit in the lower end of the water hose had been placed towards the thermostat housing with a small water leak as a result.

I also found a small leak in the thermostat housing gasket.

King James

Well, armed with much more complete data on my coolant leak (thanks everybody for dialing me in correctly) and the correct parts from 928 Int'l, I've finally found some time to tackle the coolant/seal leak from the coolant crossover housing.

The nightmare begins...first off, as anyone who has done this knows, and as a warning to anyone attempting, you have to take off an awful lot to even get at the crossover (at least on my 82 Weissach). Hours of top-end removal later, I have a shot at the front-left allen bolt. An extension w/a 6mm allen socket and it's out, so far so good. No clear shot at any of the other 3 bolts (they are angled, which makes for loads of fun/barked knuckles/trips to Sears for specialty tools) Finally was able to get an allen on the other 3, absolutely no joy! Aluminum/Steel weld nightmare anyone? I finally got an impact wrench on the right-rear bolt and it broke the head off. Great. The right-front and left-rear are rounded out from 6mm allen and force application to try and break weld...PB Blast/WD-40 no help as it has no way to get on threads.

In going back and re-reading posts related to this repair I haven't run across anyone with similar experience. I am now looking at dozen(s) of hours of I don't even know what, drilling out bolts? trying to reverse the electrolysis of the weld? I cancelled my insurance as it doesn't look like she's gonna run this summer....pretty big-time bummer for a guy w/ the usual distractions (3 kids/major rehabbing of home and rental properties/regular 9-5 gig, etc...) This is supposed to be my summer fun car!!!

Ideas anyone? (rant over, unfortunately I don't feel a whole lot better!)

dr bob

What "Impact Wrench" are you using? For bolts that seem frozen by electrolytic or chemical corrosion, the big part of the job is snapping the metal bond where corrosion has caused the parts to become one with each other. For threaded parts, this is usually on one (the tension side) of the threads. Using an impact wrench of the pneumatic/electric motor type only provides a rotating motion with the force. Ideally, you want to have some of the 'impact' transmitted axially through the bolt to reduce the pressure on the thread as you attempt to rotate it.

So-- Get one of those impact screwdriver tools, the one with a square drive on the end so you can use a socket or, as in your case, and allen-head hex drive bit. Get a set of GOOD quality bits too. Leave the cheap/imported bits in the trash can. If you are using a socket to try to pull a stubborn bolt, consider adding a nut inside the socket so the impact will be transmitted to the socket. You want the socket to stand just above the washer on the bolt head, so the impact of the hammer-blow on the wrench itself s transmitted to the bolt you are trying to turn, and not to the washer or the material the the bolts is passing through.