What am I doing wrong?

[capz]

I sanded and cleaned up my thermostat housing, installed a new thermostat and gaskets using part numbers as seen here.....

http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=809994%2098&ivar=images/CRUISER/809994.98/13.png&inbr=2705&bnbr=150&bdesc=STANDARD+COOLING+SYSTEM

.......torqued to 30 ft lbs

started up and it's leaking from bottom front. So I torqued to 50 ft lbs, same thing.

Took it off, used Perfect Seal this time, torqued the hell out of it..... still leaking.

Can anyone with this housing shed some light on what's going on?

 

[H2ONUT]

Does the book call for 30 ft lbs? Seems a bit much to me. And 50, boy are you lucky they didn't snap...

I would take it back apart and make sure all your sealing surfaces are flat. When putting it back together, spread a thin coat of Permatex, (dark grey) I think is the #2. Let it set up for a few minutes before assembly. Wait a few hours before running the motor.

If it still leaks, I would say the housing is cracked.

 

[fc3]

What Mark said, plus make sure the thermostat and insert are installed correctly. If misinstalled, they can keep things from seating properly. How did you clean the mating surfaces? You said you sanded it. Might they not be true anymore. Check with a straight edge for flatness. When cleaning metal surfaces, the 3M 2" ScotchBrite Roloc disks are great. I get them in boxes of 25 from auto parts.

Caution: Don't use the heavy duty ones on aluminum. The heavy duty ones will cut right through aluminum and be very careful with the medium grade on aluminum, too.

 

[DCarl320]

Have you ran it up to operating temp? Sometimes a little heat helps the goop/gaskets to set. Then re-torque to spec.

 

[capz]

The book calls for 30 pounds. I went to 50 out of frustration. It didn't seem like a lot for those bolts. Plus they were new. I sanded the mating surfaces lightly but there was quite a bit of gasket material and a little corrosion I had to remove. I fear I may have ruined it. It was probably time for a new one anyway. What I can't get my mind off is I remember scraping gasket material off the recess on the block, where the housing insert would sit. But according to the diagram there's only the outer gasket and the insert mates to bare metal. I dunno, I'll try the suggestions here before I get a new housing. Thanks for the feedback.
BTW it's going to be 80 here today! :thumbsup:

 

[capz]

I just want to add a suggestion to those with raw water cooled engines. Take out the thermostat every year prior to winterizing. You won't have to wait for the engine to reach operating temp and you won't run into the problem I have now in the spring.