Head Stud Sealant???

[KYGTP]

What do you guys use on your head studs to seal them?? I am getting ready to put my motor back together for the second time and want to make sure my head studs are good and sealed.

I used "Indian Head" sealant and they leaked. On my other motor I used "Avation Sealant" and that seemed to work well, but looks just like the Indian Head stuff, so I am a little scared to used it now.

Another friend of mine told me to used "High Temp Thread Sealant" by permatex.

I really don't want to have to do this again, and want to really make sure they seal this time, so what has worked for you???

[Jeff88coupe]

If the bolt holes go into a water jacket....I use teflon pipe sealant...can find it in the plumbing section at a hardware store. Little tube of it lasts forever..is like a buck.

[kennebellcobra]

Permatex thread sealant.... Are you using mls head gaskets?

[KYGTP]

Permatex thread sealant.... Are you using mls head gaskets?

No, Just stock head gasket. (that are a PITA to clean off the head.)

I used to have them on there, but some guys have a hard time getting them to seal with our heads for some reason and the first time I rebuilt my motor I went back to stock gaskets for fear of the them leaking. I still have a set at the house though.

So you say the Permatex Thread Sealant then Shannon? Small little white tube with red lettering on it? Just want to make sure I have the same stuff.


Jeff, I have also read that some guys use it at well, but with the heat, I would think it would not hold very well. I don't know though...........

[kennebellcobra]

That's the stuff.... I was going to say to use the copper spray if you had the mls.

[KYGTP]

That's the stuff.... I was going to say to use the copper spray if you had the mls.

Glad that I have the right stuff.

Yeah, on my MLS, All the rivets are out except one, and all three layers were sprayed with copper spray. Still did not want to take the chance though, when I know the stock gaskets are good to about 25 psi or so.

[bestracing]

According to Cometic, the MLS gaskets need to "Rest" in between torque settings and tighten down in three steps. After the last step you have to let it sit for awhile (don't remember how long minimum but we let it sit overnight) and then re-check the last torque setting. They also recommend to recheck the torque after a heat cycle as well. Went through this with a friends motor that we used MLS gaskets on and after following that sequence they have never leaked.

[KYGTP]

According to Cometic, the MLS gaskets need to "Rest" in between torque settings and tighten down in three steps. After the last step you have to let it sit for awhile (don't remember how long minimum but we let it sit overnight) and then re-check the last torque setting. They also recommend to recheck the torque after a heat cycle as well. Went through this with a friends motor that we used MLS gaskets on and after following that sequence they have never leaked.

That is some great info, I have never heard that before. I know when I torque down my heads, I do it in several steps/torque setting, until I get to the final torque. Once I do the final torque, twice, I let it sit for a while, then do it again, and that has worked for me on a stock gasket though.

My biggest thing right now is getting these studs to seal up and not have to worry about them leaking again. Pulling this motor in and out is getting old. I think since the beginning of the year, I have pulled this motor, 5 times now.:rolleyes: But thats racing for ya, or should I say, that it is my mistakes causing all of this.........

[bestracing]

Well with the Loctite you have and how you torque your heads you should be good to go :bigthumb

[KYGTP]

Well, Lets keep our finger crossed, I used the Peratex thread sealant on the head stud tonight, in a couple of days I will have it running.

[bestracing]

Is this on your 3.8L?

I got a question for you. I have a 3800 Series II motor in my Impala SS and I'm going to be flushing the Dexcrap out of it. Is the thermostat housing sealed with a rubber ring on the thermostat, o-ring or gasket?

[KYGTP]

Is this on your 3.8L?

I got a question for you. I have a 3800 Series II motor in my Impala SS and I'm going to be flushing the Dexcrap out of it. Is the thermostat housing sealed with a rubber ring on the thermostat, o-ring or gasket?

Yes this is on my 3.8L S/C motor.

It has a rubber ring around the thermostat, you should be good. Sometime I will put a small finger rub of RTV on the base of the housing to make sure it seals.

Be careful when flushing it so that you do not get the Dex-crap goo clogging you heater core. I would let you car warm up, find the hot side of the heater hose and mark it. That way when you flush your system, you can take the heater hoses off, and flush it backward throuhg the system to get all the crap out. If you just go from the thero. housing, you are going to push all the crap in you heater core and you will not have any heat.

If you have any other questions, feel free to pm me.

[bestracing]

I know about the heater core, happened to my brothers 93Z and a friends 2003 Sierra after flushing those. :bigthumb

My 4.3L V6 was rubbered ringed but I've had some older 60* V6 motors that were not and I wasn't sure with the 3.8L S/C. Thanks for the help