# freeze plug



## tigertiney91 (Feb 11, 2009)

I have a 1988 Chevy Silverado C1500 with a 350 5.7 engine. I had a water leak and tought it was the water pump. I replaced it and the hoses and it still leaked. Someone told me it was probably leaking from the freeze plug. Problem... I have no idea where that is and how hard will it be to replace. Anyone that can help it would be greatly appreciated.


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## bruiser (Jul 30, 2005)

There are freeze out plugs in the heads, and in the block. They're round pieces of metal that are forced into the heads or block. You'll have to crawl underneath the engine with a strong light and see if you can spot any drips coming from the freeze plugs.


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## redward (Feb 9, 2009)

If I remember correctly there are 8 freeze plugs (soft plugs) on the Chevy 350. 2 on each side,1 on each side in the front,and 1 on each side in the back under the transmission bell housing.I have found that another weak spot for coolant leaks is at the corners of the intake manifold.


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## young lion (Feb 12, 2009)

Depending on the condition of your engine from wut ive seen when a freeze plug fails it means there rustin out. To Replace drill a hole in it and run a strong screw in it a pull on the screw with a hammer or pliers. Id be checkin the bottom end plugs cuz they may begin to fail soon also.


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## Bopo (May 30, 2009)

The freeze plugs is probably suffering from a bit of corrosion :wink: which has weaken it, tbh I really don't know how difficult they are to replace.


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## mack1 (Nov 27, 2007)

Hi tigertiney91 and welcome to TSF,

Freeze plugs are just that. If the engine freezes, the water expansion will push them out instead of cracking the block. They are usually 2" or less in diameter and look like a sheet metal plug in the block. *bruiser* thinks they are in both the block and heads and *redward* thinks there is 8 of them. I yeild to both their ideas as I have never counted them, nor traced them down. I have found that there is no freeze plug located where it can be easily changed out while the engine is in the truck. *young lion *indicated how to remove the leaking plug. By design, they are cup shaped with a dimple in the center. The idea is to hammer it in using the dimple as the aiming point. By hammering on the dimple, it will expand causing a metal to metal seal between the new plug and the block. The need to hammer it in is where the problem lies. There just isn't room to get a good swing with a hammer to put the new one in. The pinging action is required to get the seal, pushing it in with a hydraulic jack will not be the same. Try driving a nail then try pushing a nail and you will get the idea. Pressing it in just won't work for me. Last time I had one leaking, I put in a can of Bars Leak with the idea if that didn't work, I would pull the engine to replace it. Luckily it lasted for several years after that. 

Hope someone has a better idea.

Wishing you best of luck,
Mack1


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