How about cutting a channel into the housing and using thick copper wire the way they used to o-ring cylinder heads in the heyday of shade tree hotrodding?

Sixto
87 300D

Are you using a OEM thermostat housing gasket? Only use the OEM seal, it seems to be thicker than the aftermarket ones. They are meant to be installed with no extra sealant

__________________
1985 300TD Turbo Euro-wagon
1979 280CE 225,200 miles
1985 300D Turbo 264,000 miles
1976 240D 190,000 miles
1979 300TD 220,000

GONE but not forgotten
1976 300D 195,300 miles
1983 300D Turbo 175,000 miles

http://i42.photobucket.com/albums/e3...e485-1-2-1.jpg

Well, I called the nearest machine shop and they said it can't be re-surfaced, I have to get a new one. I'm not really sure she understood what I was talking about. I don't see why it couldn't be re-surfaced, but I wasn't going to argue. I hate being on the phone as it is.
79Mercy, I did use the OE gasket. Three of them, so far ... I tried it with and without water pump housing sealer.
Maybe I'll go to the junkyard this weekend. Of course, if I do find one that will entail having to remove another York AC compressor, in the cold.

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

The person may have been thinking thin modern pot metal or plastic.

Take it in person to a couple of local machine shops, the phone won't work.


.

Maybe you can resurface it yourself the way 1960mog resurface the oil pump housing surfaces in this post - 603 oil pump servicing

Sixto
87 300D

That will work.

.

Thanks guys. Hopefully I'll have time to swing it by one engine shop on the way to work. Tomorrow I should have some time to play around with sanding it like in the oil pump example. I like the idea of using the floor as a flat surface, for some reason I hadn't thought of that! I also think maybe I haven't been using a course enough sandpaper. I was trying to use a sanding block with 600 grit ... I'll pick up something rougher.

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

Well ... the good news is there's no longer visable coolant leaking out of the junction from tstat housing to block, when I pump it up with the pressure tester. At first it did a tiny bit so I tightened up the bolts and it stopped. So obviously the re-surfacing helped! The bad news is, it still loses pressure, but really slowly, and I can't even hear where the air is escaping, or see coolant dribbling. I'm gonna let it all dry off and get a better look at it tomorrow. Considering the last few times, I'm willing to call this progress ...

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

Carpet under dash isn't wet?

Sixto
87 300D

I had that thought at about 3 a.m. last night ... was just about to go look. I didn't think to check last night!

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

... it's still the tstat housing. I can see a tiny stream slowly appear underneath it (different spot than before), and can hear a faint sound of air escaping. I pumped it to 9 psi and in a half-hour the needle dropped about 2 mm, if that, so it's a tiny leak. There's an awful lot of coolant all down the block, though, that doesn't look like it's come from the housing. What a mess.
I tried tightening the bolts a little more but I don't want to overtorque them (still have not been able to find specs). I guess since it's such a tiny leak, I should try it one more time, with water pump gasket sealant. I did not use it this round.
How do I turn such small projects into epic sagas ... .

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

.... annnnnd it's leaking from somewhere else too. Big puddle forms on the ridge of the block under the water pump pipe, coming from somewhere other than the tstat housing. I'll have to completely remove the stinking AC compressor and bracket now (I only had to move it slightly to the side before) ... pretty much lost my patience for this ...

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

Clean and dry both metal surfaces.
Use one of these products on both sides of the paper gasket, and install following product directions on curing time.

Permatex 22071 Water Pump & Thermostat RTV Silicone Gasket
http://www.permatex.com/products/Automotive/automotive_gasketing/gasket_makers/Permatex_Water_Pump_Thermostat_RTV_Silicone_Gasket.htm

Permatex 80057 300 Form A Gasket
http://www.permatex.com/products/Automotive/automotive_gasketing/gasket_sealants/Permatex_Super_300_Form-A-Gasket_Sealant.htm

Note: Never pressure test the cooling system above 12 PSI.

Thanks, I've got some of the first one. I think I'll get a plastic syringe to apply it because when I tried to use it before it just smeared all over. Hopefully the combination of the re-surfaced face and the RTV will be the charm.
I couldn't find the number to pressure test but I've been going up to 9 PSI; I thought it was a 1 bar system so I didn't want to get too close to that.

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)

... it's coming from behind the water pump housing, sort of in two directions, must be that rear gasket. So, not as simple as the water pump. Now I have to figure out at least how to get the AC compressor detached, which is a whole seperate project to me because I don't know anything about AC systems. I guess at least I am learning from this. I am getting a little concerned as to why every coolant gasket is failing at once on this car. From what I searched the tstat housing gasket and the pump housing gaskets aren't really common items to be replaced, but both mine went one after the other? Guess I'll just fix it and see what happens.

__________________
1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)