Leaking Coolant Reservoir Tank

This write up is for anyone that may have a leaking coolant overflow tank. This could be a quick first area to check before you pull the shroud from the truck.

Symptom: When filling my overflow tank to the full line I would immediately notice it would start to leak coolant until the reservoir reached a certain level and would stop leaking. Tried this multiple times with the same result. So I figured my overflow tank was cracked and wanted to see if I could seal it back up without having to buy a whole shroud assembly. I tried to find anything on if these could be separated and could not find any posts or pictures confirming this, so I tore into it.



Once I removed the shroud from the truck I found out I could remove the coolant reservoir tank from the shroud and it was its own unit.








I filled the tank with water, found the crack, and then ran a bead of silicone along the crack.




As you can see, if you need to remove your coolant reservoir tank, you can do so without removing the whole shroud FYI. I have been running this for 3 months (1500 miles) and it has held so far.

 

Mine leaks at the hose connection to the radiator overflow. Not much, but the pink crust is quite annoying.

 

I'd keep an eye on it. RTV silicone isn't a good adhesive and the material of construction for that tank (polyethylene) isn't an easy one to bond anything to.

I might have tried a hot melt adhesive or trying to re-weld the crack with something like a soldering pencil.

 

My thought was that I wasn't actually glueing two pieces together, but more sealing a crack like you would a bathtub, or around a window. I tried cleaning the plastic really good, because as you mentioned I was worried about it bonding to such a slick surface. In hindsight, I probably should have scuffed it up a bit with some sandpaper as well.

I thought about trying to re-weld it, but have only really read about ppl doing it and haven't tried it before. Is hot melt adhesive just using a normal hot glue gun and stick, or is there a particular type of stick to buy that will bond better?

Thanks for the input!

 

The silicone seal will not stick long on that type of plastic. Plastic welding would work. Harbor Freight has plastic welders for $15, which is probably about what you'd pay for a salvage yard tank.

 

Same here

 

Canoe and Kayak leaks are fixed with soldering irons. *little bigger than wiring but it'll work* If you need filler, trim with razor knife from a too thick spot.

 

This was going to be my next solution if the silicone did not hold. I have plenty of buddies that are pretty familiar with welding kayaks (even some of mine that I have cracked over the years) and have the tools to do so.

I haven't been super regular at checking my local junkyards but it seems like in Idaho if a Tacoma makes it to the junkyard its either parted out in a week, or someone buys the whole truck for parts.