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| | | Forums66 Topics128,049 Posts1,055,699 Members48,426 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Oct 2023 Posts: 327 'Bolter | | 'Bolter Joined: Oct 2023 Posts: 327 | Deciding whether to replace the freeze out plugs on the 235 before I install it. Appear to be in good shape and none appear to have leaked. So is it an "ain't broke don't fix it" situation or do the maintenance while it's easy" situation? | | | | | Joined: Oct 2021 Posts: 6,750 'Bolter | | 'Bolter Joined: Oct 2021 Posts: 6,750 | I like the "if it ain't broke, don't fix it" approach to automobiles.
If they're brass, leave them alone.
If they're steel, knock them out and replace them. You can even use those expandable, solid rubber plugs with a wing nut on the end. I used one to replace the rusted out core plug on the driver side near the drain plug.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
| | | | | Joined: Sep 2009 Posts: 5,816 Gearhead, Stovebolt Tech and Parts Tracker, Mod for Swap Meet and GTT | | Gearhead, Stovebolt Tech and Parts Tracker, Mod for Swap Meet and GTT Joined: Sep 2009 Posts: 5,816 | An ounce of prevention is a good rule of thumb on replacing core plugs. If you're not 100% sure, it's cheap insurance and they're much easier to replace before you stick the engine back in the truck. 
~ Dan 1951 Chevy 3 window 3100Follow this story in the DITY Gallery"My Grandpa Carl's Truck and How it Became Mine"1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)
| | | | | Joined: Mar 2004 Posts: 6,214 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,214 | Also, they rust from the inside out, so they might look good but are really paper thin... Mike B  | | | | | Joined: Mar 2007 Posts: 3,383 Crusty Old Sarge | | Crusty Old Sarge Joined: Mar 2007 Posts: 3,383 | It's just a good practice to replace the Freeze Plugs while you have access to them. That is especially true for the one behind the flywheel. If you have no history of when they were installed, it's cheap insurance. Be sure to clean up the holes with some sandpaper and use a thin layer of sealant on the new plugs. Brass is preferable.
~ Craig 1958 Viking 4400"The Book of Thor"Read the story in the DITY1960 Chevrolet C10"A Family Heirloom"Follow the story in the DITY Gallery'59 Apache 31, 327 V8 (0.030 over), Muncie M20 4 Speed, GM 10 Bolt Rear... long term project (30 years and counting) If you don't like driving yourTruck, you won't drive yourTruck..| Living life in the SLOW lane | | | | | Joined: Oct 2021 Posts: 6,750 'Bolter | | 'Bolter Joined: Oct 2021 Posts: 6,750 | If you do pull all of the core plugs, it will give you a really good opportunity to pressure blast and scrape any crud that's inside the water jacket.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
| | | | | Joined: Feb 2004 Posts: 29,771 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,771 | Brass plugs are available for the side holes in the block, but I haven't been able to locate any the right size for the big plugs on both ends of a stovebolt block. With a little creative metal whittling, a flat brass sheet about 3/32" thick can be formed into a convex plug to fit those holes. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Dec 2019 Posts: 439 'Bolter | | 'Bolter Joined: Dec 2019 Posts: 439 | Given the two choices, I vote for preventative maintenance while access is easy. The only one that’s pretty terrible is the one at the firewall side and front ones aren’t that bad but it will help assure being able to sleep at night. lol
Larry Old man᠁Old truck᠁neither one goes very fast. All you need in life is TIME, PATIENCE and MONEY. If you are missing one component, you'll need an abundance of the others two.
| | | | | Joined: May 2001 Posts: 1,904 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,904 | I use a frost plug heater under the manifold of my 261 (and previous 235) since below zero starts were sometimes needed back in my working days. I wonder if those can be used on the ends of the block. 1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
| | | | | Joined: Feb 2004 Posts: 29,771 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,771 | I use a frost plug heater under the manifold of my 261 (and previous 235) since below zero starts were sometimes needed back in my working days. I wonder if those can be used on the ends of the block. No, both end plugs are covered by other components, particularly the bellhousing. There's no room for the heated plug wiring. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
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