Leaking coolant

[MarvinElliott]

Hi
So my 84 Toyota tercel wagon is leaking coolant from this pipe that comes from the top radiator hose and also from the lower radiator hose and I do not know what it is called

[dlb]

That's the coolant bypass tube. It has o-rings at both ends, they are leaking. To remove it, you have to drain the coolant, remove the upper rad hose, and undo the two bolts that secure the aluminum outlet piece to the block. Easiest way to find the right size of o-ring is to get a big set of them (they're commonly available at auto stores and online) and try a few until you get one that fits well over the tube and sits snug in the housings. I did this job recently and they started leaking within a year so I would recommend also smearing a bit high temp sealant on the o-rings or in the housings before putting it together.

[MarvinElliott]

Do you think I can put some kind of sealer on it? Do you think it will still leak if I put sealant on it and do you think it will harm it if I put sealant on it

[dlb]

I don't imagine that will hold but it certainly won't harm anything to try it. Just make sure to clean the areas really well and dry them thoroughly, apply the sealant, and let it sit for 24 hours or whatever it says on the package before running the engine. That will give it the best chance of working.

That said, doing it properly isn't a big job. Should only take an hour, maybe two if you're slow, then leaving it for 24 hours before refilling the system.

[SirFoxx]

DO NOT USE RTV ON THAT TUBE. if its leaking after replacement either you used the wrong orings, you didnt clean the crust out of the holes, or your bypass tube is rotted.