Replaced thermostat and gaskets, but still leaking

[i'monaboat]

I have an MCM 4.3L Alpha 1 I/O and I just replaced the thermostat along with the round gasket, o-ring, and upper two gaskets that the thermostat cover goes over. Originally it had an upside down u shaped piece of metal that set on top of the thermostat housing that had holes for the bolts to go through as well. I didn't put that back on there because after putting the new gaskets and the o-ring in there it wouldn't tighten down. I've tightened the heck out of those bolts and i still have water coming out of the top of that thermostat housing. Does anyone have any idea why it would be doing this? I bought the thermostat kit from NAPA that went to this engine so i just assumed that all the gaskets went in there. Did I put them in wrong?

 

[90stingray]

Re: Replaced thermostat and gaskets, but still leaking

That metal is what holds down the thermostat. I don't think it's going to work without the correct parts installed. Were any of the parts pitted?

 

[KCKracker]

Re: Replaced thermostat and gaskets, but still leaking

if they are heavily pitted use permatex #2, its like puddy will seal anything.

 

[i'monaboat]

Re: Replaced thermostat and gaskets, but still leaking

I feel like if i put that metal piece back on there then it will leak more because of a bigger gap.

I did not see any pitting, but where would i put that permatex #2 at? Do i put it where the cover meets the housing? Where do i get permatex #2?

 

[Brewman61]

Re: Replaced thermostat and gaskets, but still leaking

That part, if I recall, is a place to attach the engine hoist hook. I'd think you'd want to have that in there possibly the bolt length depends on that metal spacing? Along with making sure you're using fresh gaskets and that you've thoroughly cleaned the sealing surfaces and used correct torque. Then see if it still leaks and go from there.

 

[i'monaboat]

Re: Replaced thermostat and gaskets, but still leaking

I'll put that part back on there then. There are fresh gaskets because i bought the whole kit from Napa. I didn't user a torque wrench. I just tightened the hell out of it.

 

[i'monaboat]

Re: Replaced thermostat and gaskets, but still leaking

I put the permatex on there and that seemed to stop the leak. I also put that metal piece back on there as well. Hopefully that will take care of everything. Now we've discovered that the shifter cable will need to be replaced.