Thermostat Gasket

[ROBDOG1]

I have been working on the boat all day getting it ready for winter ( 4.3 merc)
I have all the drains out (a ton of water came out) except one on the top of exhaust manifold. It is all rounded and I can't get it out. Is this a big deal because? there is drain on the bottom and i drain it all out.

Question I took off the therostat and will be pouring anti-freeze down it, will a gasket from the auto parts store be ok? or do i need a special one or just bolt it down tight?

Thanks

 

[wire2]

Re: Thermostat Gasket

An automotive one is fine. If you put it on dry, by next year it will probably be stuck to both sides and be destroyed when you pull the T/S housing off.

I put a film of silicone gasket on one side, gear oil on the other, have been using the same one for several years now, seals perfectly.
They're cheap enough, it's just the bother of going to get a new one every fall.

 

[Don S]

Re: Thermostat Gasket

Merc has used 4.3's with a number of different manifolds and risers. Does your's have a year???? They do change you know.
There is also a number of different plugs in the manifolds, can you post a picture of the one you are having a problem with so we know which one?

 

[ROBDOG1]

Re: Thermostat Gasket

Thanks Don, yes it is a 1993 serial # 0F074464. I will try and get pics tomorrow. It is the one on the passenger side.

Thanks

 

[ROBDOG1]

Re: Thermostat Gasket

Here is a pics of the drain plug.

Thanks

 

[Don S]

Re: Thermostat Gasket

Actually, I meant INTAKE manifold, and instead of risers, I meant Thermostat housing. There are 2 different designs of thermostat housings for that vintage.

 

[zbnutcase]

Re: Thermostat Gasket

NO need to pull that plug!!!!!!!

 

[ROBDOG1]

Re: Thermostat Gasket

oh the theromstat I just pulled it off and applied some pematex gasket and tighten it up.....it didn't leak.

Thanks

 

[Don S]

Re: Thermostat Gasket

You're going to have to replace it next time, so why don't you find out exactly what you have and what you need NOW, while the pressure is off ??????

 

[dubs283]

Re: Thermostat Gasket

oh the theromstat I just pulled it off and applied some pematex gasket and tighten it up.....it didn't leak.

this time...

agreed, don

find the right gasket now, seeing as how you won't be in dire straights out on the water with a leaking gasket

i still don't know why people pull the t-stat housing to pour antifreeze in the block - there is no need to spend extra time and money on a process that doesn't help at all

all that is needed is to remove the circ pump hose at the t-stat housing and pour antifreeze in until it comes out the block drains on either side, wait until all the antifreeze has drained out and reinstall the plugs - done deal

 

[Bt Doctur]

Re: Thermostat Gasket

That plug on top that you referr to is removed only for emissions testing.It is not a drain plug.

 

[Searay87]

Re: Thermostat Gasket

As to why people remove the T-stat housing that's what the Merc sevice manual I have says to do. I agree it' s easier to remove the large hose to the circ pump. It could be to force you to visually inspect the thermostat. Some posters here advocate annual replacement of the stat. The former owner of my boat showed me the easy way. My temp gauge was not reading right so I decided to pull the housing to get a look at it. Glad I did. I posted a picture of it in this thread.

http://forums.iboats.com/attachment.php?attachmentid=68007&d=1284851598