Club Cobra

Club Cobra (http://www.clubcobra.com/forums/)
-   FE TALK (http://www.clubcobra.com/forums/fe-talk/)
-   -   Hex Freeze Plugs (http://www.clubcobra.com/forums/fe-talk/145649-hex-freeze-plugs.html)

Lalmeida617 02-12-2022 10:45 AM

Hex Freeze Plugs
 
Hi guys I could use a little help with #634. It has 427 Cast iron side oiler. I have some noticeable leaking from several freeze plugs. They are hex screw in type. Do I need to drain the entire system to reseal them? Or can they just be unscrewed and resealed? Is there a certain sealer I should use? Should I buy new plugs or reuse the old ones? They don't look rusty. Any help and advise would be helpful.

Grubby 02-12-2022 04:33 PM

When you unscrew one, it will mostly drain the system. It would be much cleaner to drain via the radiator petcock first.

John

KarlzEE Bebout 02-13-2022 07:19 AM

BTW, I'm sorta doubting that what you are referring to are "freeze plugs" but rather they are drains. If they are threaded in, do you suppose that they would release the liquid's frozen pressure?
Back to your actual question: I've had good results using 3-4 wraps of QUALITY teflon tape on the threads. Also, ARP makes a "thread sealer" that must be excellent to carry the name. Lastly, plumbers have been using "pipe dope" to seal threads for decades, if not centuries. My 2 1/2¢ worth.

Grubby 02-13-2022 08:07 AM

Side oilers do have threaded "freeze" plugs on the sides of the block.

I worked in automotive manufacturing for many years as an engineer. I was specifically involved with the 2007 Ford Powerstroke.

The "freeze" plugs are used to get sand and excess cast iron out of the block at the end of the casting process. They are not intended to protect the block from freezing.

John

DanEC 02-13-2022 10:43 AM

I think they are actually for both purposes but their usefulness to protect a block from freeze damage was pretty much negated with the introduction of antifreeze many decades ago. The manufactures just stuck with the standard friction fit core plugs as they were cheaper than threaded plugs and under normal conditions, served just as well.

KarlzEE Bebout 02-13-2022 01:05 PM

I can't wrap my head around the idea that threaded plugs would blow out if the coolant expanded due to freezing. Maybe they would be the weaker point but I'd think the block would crack sooner than the threaded plugs would be forced out.

Has anyone actually had the experience?

DanEC 02-13-2022 01:25 PM

I don’t think your getting the point. They are no longer considered freeze plugs because frozen engine blocks are no longer a concern in the industry due to the widespread use of anti-freeze. Now their sole purpose is to remove mold casting sand from the coolant passages at the foundry. Ford must have figured a friction fit plug might be a reliability issue in a engine that would be run extensively at high rpm (including the water pump).

patrickt 02-13-2022 01:53 PM

Quote:

Originally Posted by DanEC (Post 1503354)
Ford must have figured a friction fit plug might be a reliability issue in a engine that would be run extensively at high rpm (including the water pump).

No. They're actually called Welch plugs. And for your absolutely arcane automotive factoid for the day, read this:

https://www.britishcarweek.org/welch_plug.html

Grubby 02-13-2022 05:37 PM

That is interesting.

A lot of great engineering ideas are mistakes or accidents that show a better way.

John

Lalmeida617 02-14-2022 05:13 AM

Wow guys. Ok guys. So to fix the Freeze,Welch, hex clean out plug leaking issue. I must drain the radiator remove plugs with a hex wrench that I will make, and then seal each plug with a high temp rtv? Keep in mind that area gets kinda hot. Is this a common issue on SO?

patrickt 02-14-2022 09:41 AM

Quote:

Originally Posted by Lalmeida617 (Post 1503382)
Wow guys. Ok guys. So to fix the Freeze,Welch, hex clean out plug leaking issue. I must drain the radiator remove plugs with a hex wrench that I will make, and then seal each plug with a high temp rtv? Keep in mind that area gets kinda hot. Is this a common issue on SO?

I have never personally touched a side oiler's screw in freeze plugs. But since no else is going to give you any help, I'll refer you to this topic on the FE forum: https://www.fordfe.com/screw-in-free...nt-t95234.html

Grubby 02-14-2022 01:31 PM

I suspect leaking isn't common. Patrick's link has some good suggestions on sealing the plugs.

I noted one guys comments that the screw in plugs were to make the block stiffer.

That makes sense. Ford had bottom end issues on 427s in NASCAR. A screw in plug costs more, but if it allows you to win races on a low volume engine, then that is a good reason.

John

601HP 02-15-2022 03:58 PM

Core Plug Removal
 
1 Attachment(s)
This screen shot is from Steve Christ's book titled HOW TO REBUILD BIG-Block FORD ENGINES, pg. 69.

Lalmeida617 02-15-2022 04:19 PM

Quote:

Originally Posted by 601HP (Post 1503427)
This screen shot is from Steve Christ's book titled HOW TO REBUILD BIG-Block FORD ENGINES, pg. 69.

Thx 601. Believe me I don’t want to remove them. But I guess I have no choice, I have to either live with the leaks or replace them. Anyone know if they are NPT or straight pipe?


All times are GMT -7. The time now is 06:08 PM.

Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: