I changed out my water pump this weekend...

almost did my timing chain... but chickened out. (afraid I might screw something up.)

But anyways. I bought a new thermostat and rubber seal.

but everytime I start the car. It Leaks...
In between the seal and out of the screws...

I have tightened the screws as good as I can.

Do I need to use some liquid seal of some sort?

What to do??

Click for large view - Uploaded with Skitch

Click for large view - Uploaded with Skitch

First off, good job so far! I would clean that black stuff off the mating surface with a wire toothbrush, then a THIN coat of blue RTV around the mating surface of the T-Stat housing ( the dome part you took off), put it all together and DO NOT OVER TIGHTEN! I install mine with a 1/4 drive ratchet so as not to over tighten. Give it about ten min or so to "set up" before you start the motor.

This is how I do my t-stat swaps twice a year. I run a 160* in the summer, and a 195* in the winter. SEAMS to keep it cooler in the summer and better heat in the winter. . .

Is it just seeping a tiny bit or is it more than that? Clean the recess in the intake, get a good piece of 220 grit wet/dry sandpaper and place it on a flat surface, attach it some way, 2" tape all the way around, then put your thermostat housing on it and work it in a figure 8. Do this about 20 times and check the bottom, if it's warped you will notice some areas not touched by the sanding. Keep doing this until its nice and flat, you may have to use a couple pieces of sandpaper. If it's warped bad, you may be time and money ahead to replace it. It should seal with the rubber O-ring without using any RTV, but a thin, thin coat of sealer wont hurt anything. Don't over torque the bolts as this can cause problems too.

If the bolts thread into a water jacket, you will need some thread sealer on them.

Also it looks like you have another gasket in the block still remove the old gasket...

If you have a chrome housing they all leak until you take them to a belt sander and make them flat on the bottom... Just a thought , it is what I had to do.