the flyin' scotsman

I have an anti-freeze leak thats coming from the lower rear engine.

Engine running with air box off there's nothing evident leaking topside around the hot water valve, hoses etc.

Looking underneath its dripping from the clutch inspection cover area but it could be running from another source. I did have the block drain bolts out this past winter

Timely advice is appreciated; car is enterd in a show and shine tomorrow.

Herman K

check if the pressure switch located next to the reservoit tank is cracked and coolant follows hoses lick a wick to that area

Calgary Ole

Malcom, when I bought mine it had a substantial leak near the bellhousing on the passenger side. Turned out to be a crack on the bottom of the expansion tank that traveled down along hoses/fuel lines etc and appeared to be from the back of the motor. See if the tank is holding pressure.

Just a longshot to check out. Good luck!

Mrmerlin

check the heater control valve, if it looks old replace it as well as the short hose.
Also check the well drain there is a chance one of the heater hoses are leaking at the heater and then the coolant will run into the well

the flyin' scotsman

Just a quick update............I pushed the car back from where it was parked in the garage; engine off and its not leaking so the issue is pressure related. My a/c is now working after many years not.

Thanks Ole, I checked around the res...............dry as a bone.

Stan, as per the 1st post I have the air filter box off and clearly see the water valve and associated heater hoses as this was what I first suspected.............all are dry. I should add the valve is new and wired closed.

I also removed the plastic cover at the firewall to check hose from the heat exchanger...........dry.

I'm about to remove the front wheels and get underneath it for inspection of?????????

928 at last

Hey Malcolm,
I've got a seep from the resevior tank. Not dripping from the rear of the engine yet, but it's definetly pressure related and I just spotted the whiteish residue on the tank. Not sure yet if the tank itself is suffering from old age although I can see some surficial cracking in places, or if it's the level switch unit. You really may want to check.....maybe the best bet.
I know the block can weep too. I'm assuming though that you torqued to spec etc., so improbable.
Best,

928 at last

Should note, my res. looks dry 99.9% of the time.. There's a dimple in the centre though, and if you use a paper towel, you can check and see what's not evaporated from the bottom.

the flyin' scotsman

More clarification..............with the engine running it leaks as in pissing out. The a/f is dripping off of the clutch inspection cover at a consistent rate. Engine off no leak.

From what I can see there's no evidence of a/f leak at the res., the heater valve and associated hoses from the topside of the rear engine.

928 at last

OK, sounds like is isn't a minor thing with the res. Assuming that there's residual moisture, you could always try the "Talcum Powder Test" and look for the high point or "High Water Mark" as we used to call it.
You'll have to rinse the whole thing down thoroughly when done, but........

PorKen

An old coolant pressure sensor (behind the washer fluid fill tube) can leak when the engine is hot and running, but that's a long way from there to the clutch housing.

the flyin' scotsman

I believe, hope and pray I found the issue.

With the car hoisted high on the PS, front PS wheel removed, engine running I crawled underneath for a look see, consistent drip coming off of the PS of the bell housing but no evidence as to where............now starting to fear the worse; cyl head gasket. I look and look trouble light in hand and see nothing that confinces where said a/f has sprung.

Crawl back up and with the car and the extreme lift angle I now see a 'river' of coolant coming from the water valve area but the valve is dry as are the hoses. Lower the car to a normal stance and the 'river' disappears from my uptop view but still leaking. Further inspection of the new 'little' hose from block to valve reveals that although the clamp is tight the metal piece that the hose clamps to is loose.

Shut the engine off, cool off for a while (one, ok 2 beers) and there lies the issue...............the metal insert that is in the engine block to water valve hose is free; as in I can pull it off the portion thats bolted to the engine.

Its obvious that on assembly 21 years ago Porsche applied some sort of glue to seal....................any suggestions?

My inventory of glues is limited and its Sat night in farm country.

Thx to all for previous inputs.

928 at last

Watchya got in the box?
Some form of high heat epoxy is probably the best and most reliable solution, (JB Weld or Quick maybe? around here, in farm country everyone has a supply....) barring that, you could probably do tomorrow with some silicone sealer for a temporary patch.

928 at last

Just a footnote, I know people who (Not on our cars) have repaired engine blocks with JB and it's actually worked, and held. You have to be really particular about the prep, especially on aluninium, but it does work.......

Lizard928

This has happened before and JB weld has been used with very good success.

Calgary Ole

Malcom, what was used originally I do not know but I have had success with JB Weld on other cars for high heat locations. Also it can be ground off later for another product if you choose.