Amazon: Coolant Leak- top hose

[Splinelube]

Originally Posted by Derek UK

Gasket easily made from a food packet, pizza bo
https://www.classicvolvoparts.co.uk/...ts_and_Housing

Derek my car is a 1966 with a B-18 with expansion tank. Your references for thermostats indicate two: 1 "up to 1966 without an expansion tank" part 418325 and one for"1967 on with expansion tank" part 419333. Am I correct in assuming that even though my car is a 66 that the latter with expansion tank is appropriate? Truly appreciate your help on this forum Russ

[Derek UK]

If you look at the link you will see two thermostats. They have a different temperature ratings. Make your choice. If your temp gauge always stays up near the top use a 77º. It's not a cure but NY summers can be hot, it is on the same line as Spain. The 82º maybe better for the winter. In the old days thermostats and oil used to be changed for winter and summer. From the pictures you can see that the housings have different diameter top outlets. The later ones for the radiators that use an expansion tank have a larger outlet. The matching radiator has a larger inlet stub too. That means it uses a larger hose. You just have to have a matching set-up. Don't use the smaller early housing with a late expansion type radiator as neither standard hoses will match. You say that you have spare housings so I hope you have one of the larger ones. They are interchangeable, only the outlet diameter is different. With the right parts on hand you can sort it out in less than 1 hour. Give the underside of the housing a good clean and the same with it's matching face on the head. There is no gasket, the rubber ring on the thermostat makes the seal but a light smear of grease on the housing and head faces is good. A smear of copper anti seize on the bolts is good too. Good luck.

This might be helpful.

[mocambique-amazone]

The missmatching game with the radiators and the thermostat housings I did play too in the past......
Good evening, Kay

[gothamus]

Originally Posted by Ron Kwas

Richard;

...a bit late to the party, but I'm happy you got this sorted enough to make it home...it is not clear to me if Tstat housing itself is fractured or if gasket around Tstat somehow failed, or what the precise manner of failure was (remember also for future minor Cooling System failures, that simply removing the Pressure Cap is sometimes enough to stop a pressure leak, and allow continued driving - while monitoring engine Temp carefully)

...in any case, be advised that the rubber gasket sits around Tstat and is preloaded to seal by the recess in Tstat housing...there is NO further gasket required (or should be installed!) between Housing and Cyl Head...in fact, installing one would decrease the preload and intended sealing ability on the rubber Tstat gasket, so don't install one! Do however tighten the Housing securing bolts evenly and don't overtighten, as the cast Alu Housing is brittle and can easily be broken in this manner!

Cheers from Connecticut!

I missed this, been bogged down in work. Getting back to fix the issue- replacing housing. While up there and having swapped the rubber gasket, thinking that was the issue, I ran the engine and let it heat and start cycling through the thermostat. This time I could look closely with the glasses on and about the point of leak I could see the crack. Obvious at that point. Never sealed the housing, understanding the seal made at the rubber gasket. The point about bolts is good as I felt that too tight was bad, but not sure why.
The JB got me home. But that patch lasts that long and after a drive I have drops squeezing out where it can. New housing arrived last week. Full clean and flush of engine is my work here. I hope I can effectively run water with a hose from the rear pipes. I should test the gauge thermostat as well, but if bad it seems difficult to find a replacement.