This happens to be on a 2002 Century

Not leaking a lot, a 12oz soda bottle every few days......

Researching this , it seems common that radiator fluid leaking due to the gasket being deteriorated or loose bolts, is a common problem.

Was leaking, last year I tightened down the 4 main bolts, but could see/reach the end ones, particularly on the Driver side, near the thermostat. (that is the area of the leak)
Tightening did help, and they were loose (got a half to 3/4 turn on some).
It seemed to stop it for almost a year.
I notice it it leaking again. Same area.

Two questions,

1) anyone know where the end bolts are near the thermostat ? a pic or diagram ?

2) Since I'm not going to pay or replace the gasket myself, the only 2 options are to re-tighten
and/or try some leak sealer. Can anyone recommend a brand/type to use ?

Bight the bullet and replace the intake gaskets. The intake bolts are not supposed to be "tight" I was surprised at the inch lbs of torque they are considered tight at.
Felpro makes some very good gaskets to correct the problem. My friend put it off and ended up locking the engine in less than 2 miles.
It'* just gonna get worse.


Here is what it looks like replacing gaskets

You can see the two bolt holes in the heads on the drivers side. I think those are the ones you wanted a picture of.

The gaskets in the post above are Victor Reinz. They make an economy gasket thats ok, but as you see I'm replacing them. I went all out and had the heads reworked also.
Car runs great and should last a long long time. It has 139,000 and no CEL. The 3.1 was a poor design as far as the intake. This is a 1998 Century.

To just change the Intake gaskets you could do it in a day. Take pictures and label things. The electrical connections don't connect to anything but what they should.

The leak is very minor, sometimes not at all.

I put a cup or two of water in every week or so.

Is there a product that I can put in the radiator, that will seal the gasket ?

Now days there are many, in the bottle, products, head gasket sealer etc..
I'm not crazy about using those type of things, but if it works it would be worth it.

I don't think you will find one tech here that will recommend a fix in a bottle, because they tend to create other problems as well.....

Those lower intake bolts have a specific sequence and torque to them, and it is not much, just inch pounds....so you can easily over torque them.....and they need sealant on them....

I wish we had an easy button for you, but those gaskets will have to be replaced. Any product you add to the coolant a fix a leak (whether it is a radiator leak or a head gasket leak) will cause more problems than it fixes. It tends to clog up small passageways, and your cooling system will never perform as well with that stuff in there. Cranking on the head bolts could warp the heads. Continuing to add water is a temporary fix, but the condition will only get worse.

Well, you better test those head gaskets, otherwise you will be doing the job twice.....