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Engine block freeze plug leaks

Is it necessary to have a slow antifreeze leak from an engine block freeze plug repaired. It is not enough to puddle on the floor. A light frothy pink crust develops at the leak. I estimate it is less than a cup a month given the radiator fluid level. I would guess a $1G+ to repair.

What do you base your guesstimate on? Freeze plugs themselves are very inexpensive, and changing one out is typically as easy as tap out the bad one, and tap in the new one. Especially since you can see it, it may not be too difficult to get to. Getting the right size is the most important thing, since it is a friction fit.

But, you will need to replace it. It is a slow leak now, but they tend to grow, and may blow out at any time, leaving you stranded. The leak is a warning you caught early.

It’s a V6 transverse mounted engine. Very little clearance - air conditioning compressor on the left, oil filter on the right (which can easily be removed), exhaust manifold hanging down in front + radiator fan. If by “tap” you mean swinging a hammer I don’t see that as workable unless you remove some of the above. Maybe there is a specialize tool for this type of work.

My cost estimate is based on having the work done in a shop - drain fluid & remove some of the above to get access. You would have to work from under the vehicle.

I doubt it will cost that much to replace a freeze plug, unless you have to remove the engine to get to it. From what you describe, it would be a couple hours work at the most, probably between $200 and $300. Yes, they do make freeze plug installation tools to make installation easier, but few mechanics actually own them since freeze plugs rarely go bad. Most of the time, a socket and a hammer does the job just fine.

lose one freeze plug, lose them all. the correct tool for pulling a freeze plug is a slide hammer. you drill a hole in the plug, and then put the screw tip on the hammer and pull it out. You can pull one with a screw driver, but you run the risk of knocking it into the coolant gallery. Once one starts to leak, it will soon get a bigger and bigger leak, and on a hot day it will blow and you will be dead on the road. No doubt the cost of this repair has more to do with access to the plug than anything else, and you may well need to pull the engine out to get to the plugs. some engines have additional plugs on the end where the tranmission/transaxle mounts, and cannot be replaced without seperating the two parts. Put in brass freeze plugs instead of the cheep steel ones the mfg put in, and avoid this problem in the future. Now, just wait for these pros to tell me how wrong I am ha ha, as I am only a shade tree guy who hasnt had to do this job since 1977 on a ford pinto. anyway good luck to you.

The old plug can usually be pried out with a small pry-bar…They make rubber expansion plugs that work just as well as the metal ones. If you can see it, you can change it…

Thanks everyone for the input. Though I was driving another vehicle, I stopped by the Toyota dealer just for kicks today to see what they had to say. They suspect the fluids are actually leaking from the water pump even though the pink crusty residue is forming on the freeze plug. Possible I guess. The van only has 46000 miles so they were not sure why the water pump would have failed at that low a mileage. It’s also never been in freezing weather.

I was a little high on my cost estimate - still they estimated $650 to replace either the freeze plug or water pump - I know - an independent shop will do it for less. I always like to make repairs myself if I can but I won’t tackle a water pump in a transverse engine. Did that once and that was enough. Too tough without a lift and a good set of tools.

I developed a pinhole in my 1995 Mitsubishi Mirage’s freeze plug. Rather than spend the $140-$240 to replace it just yet, I scuffed around the area with a wire brush, kneaded up a ball of JB Kwik, and stuffed it in there. The patch is holding so far!

Iron - tite from Napa until you can fix?