So my 1999 ranger started to dump a puddle of coolant everytime I drove about 6 months ago. Took it to my mechanic and said it was the water pump and possibly the timing cover gasket as well. Was 200 for the water pump and another 700 if I wanted the timing cover too but said it was just the water pump for now. Just got the water pump done for 200 and a couple weeks later the same coolant puddle appeared. Another mechanic I know recommended bars stop leak tablets or alumaseal. I crushed up a couple tablets into my radiator and it stopped the leak for about 3 months. Again the leak appeared and this last time I put in about 4 more tablets. The leak has been gone for about 6 months now but I'm worried on the reliability of this method and if anyone out there has any similar experiences since 700 to fix that gaskets is almost not worth it. Could this cause oil and coolant to mix if the gasket ever completely fails?

this is the product i used and its been working for about 6 months now

 

You can use ground pepper as well to stop small leaks temporarily

These are temporary fixes, the particles will leak out where a seal is bad and block it, but pressure behind it will push out the particles until new particles replace them, then repeat, until particles are all used up
It can never stop the leak permanently

The tablets work better than ground pepper, lol, as they use a material that will swell a bit after being submerged in coolant and then come into contact with air, like when it leaks out of cooling system, so they work well, but will be pushed out over time

Just a heads up, if there is build up inside heater core or radiator tubes these particles also can block those tubes, it won't block clean tubes as they are too big of an opening
So after using this type of fix you should do a reverse flush to try and clear the system of these particles as much as possible
Assuming you do the repair of course

And if you will continue using this method I would do the flush and clean every year, before adding more
i.e. drain all the coolant, reverse flush heater core, pull out radiator and flip it upside down to reverse flush it
Refill with new coolant and add the tablets

If coolant ever gets too low and engine over heats you WILL BLOW a head gasket, which will cost quite a bit more than timing cover gasket repair
So check rad coolant level every day when engine is cold
3.0l uses an "overflow" type system to replace lost coolant when engine cools down, and this system doesn't work if there is a leak in the rad/engine side, it sucks in AIR via the leak point instead of coolant from the Overflow tank