bigearl56

I think I have a bad freeze plug behind the right motor mount as antifreeze is dripping off mount. Can this freeze plug be changed in the car? if so, instruction appreciated. Motor is a small block.

Earl

tbarb

Earl,

Make sure it's not coming from a head bolt. These bolts go into the water jacket and can require sealer.

GTOguy

If it is a freeze plug, it usually can be replaced in-car. Procedure is to drive it into the block with a drift and pull it back out with pliers. Install the new one (I like brass) using a socket and and extension as a drift, and good to go. If it's too tight, and you want to keep it going without major surgery, you can install one of those rubber expanding freeze plugs, available anywhere. I've seen them hold up for decades...they just look hokey. Super easy to install, though....just tighten a nut and it expands in place.

tbarb

Plus, one other thing to think about trying is a few of these stop leak tablets. They can be bought from the local auto parts store and are made specifically for this type of leak.

I have read the factory used 2 of them on every vehicle.

6D2148

That is great for emergency, but it cloggs holes and passages, rads and heat cores are made up of passages, that are not as open now as they were when new, freeze plugs rust out so you cannot cure that with stop leak. Chip

MikeM

It doesn't clog anything unless there is oxygen/leak present. If that plug is new or near new and is just weeping around the perimeter, I'd use the stop leak.

On the other hand, if that plug is original/old, I wouldn't trust it as the plug could just give way without warning.

I've used stop leak on a number of applications and never had any problems after that, including leaks in almost all cases. So have a lot of others.

bigearl56

I checked the head bolts and they look OK. I guess I need to brace the engine and remove the motor mount to see what's what. Wish me luck. Thanks for all the replies.

Earl

6D2148

While your are at it take a gander at the other freeze plugs, how many times do you want to do this, not saying do them all but take a good hard look! Chip