Freeze plug

[Low84]

When a freeze plug goes out on a motor, what does this usually mean? Reason I'm asking is a used motor I'm planning on buying needs one replaced.

By the way, we DON'T have cold weather down here. What else could it be. Block expanded/warped?

[drbyrdman]

you going to rebuild it? if so replace all of them.

[Low84]

Originally Posted by drbyrdman

you going to rebuild it? if so replace all of them.

I hope not! I'm not planning on it any time soon. But he did notify me about the freeze plug needing to be replaced and when I went to take a look at the engine, I noticed a lot of liquid (couldn't really make it out) on the crossmember lip. The engine is still in the other truck.

[Low84]

I'm just scared to buy an engine that is on it's last leg, and honestly my budget would be wrecked if I had to rebuild a 454.

[tvblazer78]

A freeze plug can be replaced with out rebuilding the motor, you will have to get a freeze plug kit then tap it in. You should be good to go after that...

[Albatrossian]

If they're not brass, they're usually steel.. they just rust to pieces. Not a problem.

[Low84]

I can sleep easier tonight. Thanks a lot guys.

[84 400]

yeah I have seen them drop out in the spring on a 500 big block caddy. they just rotted out (they where steel). I would look the block over very carefully. IT is more common then you think but would be a large concern to me.

[Low84]

That's what was concerning me, that the block actually cracked for whatever reason and the freeze plug gave out at the same time.

[JonnyTechMech]

When I bought my GMC with a 305, it had set up for 4 years. I had to tap out and replace a corroded freeze plug behind the starter. I drove it for 5,000 more miles with no issues. But when the block froze, it didn’t pop one plug.

[Low84]

Man! That's exactly what I'm trying to avoid. It's a nice built 454 for drag racing, but with all the mods it had a 13.2 sec pass seemed kind of off. It'd be nice to have a fast truck, but I can't afford to buy another engine down the road, I need something that'll last me a while. Thinking of just buying a short block 350 and building from there with all new parts and peace of mind.

[84 400]

ahh a race motor....l hmm this seems off to me too. especially if it was recently built. The saver route is to build a 350 short block. But if it is a solid motor the 454 would defiantly be more fun. Do you have a friend that builds motors? might not hurt to have a very knowledgeable person look at it with you for a second opinion. If your seriously considering the motor might be a good idea to pull the pan as well and have a look. This is not always possible but it does not hurt to ask.

[Low84]

Originally Posted by 84 400

ahh a race motor....l hmm this seems off to me too. especially if it was recently built. The saver route is to build a 350 short block. But if it is a solid motor the 454 would defiantly be more fun. Do you have a friend that builds motors? might not hurt to have a very knowledgeable person look at it with you for a second opinion. If your seriously considering the motor might be a good idea to pull the pan as well and have a look. This is not always possible but it does not hurt to ask.

I do, but I don't want to put him in that position (although I might just have to). He recently opened up his own performance shop and specializes in lsx swaps. Well the guy I'm planning on buying the 454 is selling it because he's taking the truck to my friend to get a 6.0.

Anyway, here is the pass of the motor in it's current home:

YouTube - lahyper

He did two passes before the track officials stopped him because of the leaking freeze plug. Don't know if it went out due to the run though.

[Albatrossian]

You could always do a compression check to check for cracks, too.

[Low84]

Originally Posted by Albatrossian

You could always do a compression check to check for cracks, too.

That might just be the only other option. Thanks.

[Vixvega]

Wooden dowel and just a lesst han zero guide coat of blue loctite around the outside. Comp test on all cylinders and try to determine if it went from in or out side.