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Leaking freeze plug behind starter

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Old 09-01-2023, 05:01 PM
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Leaking freeze plug behind starter

Hello everyone, I went to change my starter today and noticed a small leak at a freeze plug directly behind the starter. It looks pretty straightforward has anyone ever replaced this particular one with the engine in the car.

Im guessing driving in the new one might be a little tight of an angle because of the k-frame. I just don’t want to knock out the old one and have a hard time getting the new one in. Can anyone please chime in. I would greatly appreciate some help
Old 09-01-2023, 06:21 PM
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Re: Leaking freeze plug behind starter

If installing a standard replacement becomes a problem, a semi-permanent solution could be a screw-expansion plug.
Old 09-02-2023, 10:59 AM
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Re: Leaking freeze plug behind starter

Can't tell you that for sure, since it depends strongly on the tools and whatnot that you have available.

But I CAN tell you that there are 7 others in that block that have been immersed in the EXACT SAME coolant under the EXACT SAME conditions for the EXACT SAME length of time, and are therefore very likely to fail the EXACT SAME way (rusting out from the inside) before very much more water passes under the bridge. Not a pleasant prospect butt unfortunately it's the reality. Expect trouble with the others soon enough.

Vader's suggestion is a suitable stopgap but don't expect the whole deal to be permanent. (not that the expander plug will fail; butt others will)

Use brass replacements so they don't fail the same way again.
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Old 09-02-2023, 03:10 PM
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Re: Leaking freeze plug behind starter

This particular plug is a common issue on 3rd gens. You can change it by moving the starter over. Make sure you have the proper tool to reinstall it.

Old 09-02-2023, 07:21 PM
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Re: Leaking freeze plug behind starter

I did look at the other freeze plugs and they appear to be not leaking. I also know that there are ones behind the bell housing. I understand that the other could spring a leak in the future, I am in the process of building a 350 and definitely will go with brass ones. As far as a tool to drive them in it’s just a socket with an extension right?? I just don’t want to want to paint my self in a corner as I need to still drive this vehicle until the 350 is built
Old 09-03-2023, 10:07 AM
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Re: Leaking freeze plug behind starter

just a socket with an extension right
Yup. Kind of a no-brainer. They're like a rubber puck with a bolt through the middle and 2 big washers; the bolt squashes the puck and makes it bulge out to seal.

There's no difference in the likelihood of failure for that particular casting sand exit hole plug and any other in any motor, in any chassis. These cars are no more or less likely to fail that one than any of the others. 2 on each side, 2 on the front, 2 on the rear. 1 chance in 8 that any given one will be the first to rot all the way through from the inside where you can't see it until it makes it all the way through. You can't tell by looking at them how soon they'll fail: might look perfect and brand new this morning and be leaking by the evening. "Inspecting" them is worthless. Rust on the outside is not how they fail, therefore doesn't tell you anything.
Old 09-03-2023, 10:08 AM
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Re: Leaking freeze plug behind starter

Originally Posted by zupta82
I did look at the other freeze plugs and they appear to be not leaking. I also know that there are ones behind the bell housing. I understand that the other could spring a leak in the future, I am in the process of building a 350 and definitely will go with brass ones. As far as a tool to drive them in it’s just a socket with an extension right?? I just don’t want to want to paint my self in a corner as I need to still drive this vehicle until the 350 is built
I’ve never seen it done with a socket extension. But I’m not saying it can’t be. They make freeze plug tool kits to install it properly. It has to go in perfectly straight. If you look at the motor you will see that rear plug sits lower than the rest. I think that’s why it rots out faster than the others.
Old 09-04-2023, 02:16 PM
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Re: Leaking freeze plug behind starter

I’ve never seen it done with a socket extension
He was talking about the rubber expanding kind.

They make freeze plug tool kits to install it properly.
Indeed; a bushing driver also works, or even, a large socket that sits about 1/16" inside the plug. Needs to be large enough to drive it in evenly but leave enough space around it so that it doesn't get captured by the plug when it is compressed to a smaller diameter by being driven in. Guess how I know about this. ​​​​​​​

​​​​​​​that rear plug sits lower than the rest
Not sure how height would influence corrosion coming from the coolant that all 8 are equally in contact with. Maybe I missed something in chemistry and physics classes?
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