[rcush]

Two weeks ago I was up at a Test and Tune session when on the top end the car came loose and I went into the wall. Destroyed the fiberglass front end and banged up the passenger door and rear quarter. The next day I found the rear freeze plug missing from the drivers side. Water under the rear tires is never a good mix.

The good news is the motor was not hurt and I ran my quickest pass of a 9.68 (mph was 123 but I was going sideways through the traps). Judging by the 1/8th mile times I on was on a mid 9.50 pass.

New front end is on the way from VFN, am looking for a new door and rear quarter. So before I put the new freeze plug in I wanted to ask what all of you guys use to retain them in the block.

Thanks,

Bob
1968 Firebird (2735 lbs with driver)
463 CI
KRE High Ports

[Brian Baker]

Rather than focusing on how to keep them in the block, you may want to focus on what is causing them to pop out. Combustion pressure from a head gasket breach is the #1 cause.

[screamingchief]

Originally Posted by Brian Baker

Rather than focusing on how to keep them in the block, you may want to focus on what is causing them to pop out. Combustion pressure from a head gasket breach is the #1 cause.

Good point mongo.

Lots of guys use a lower rated radiator cap for that reason,logic being it's better to push a bunch of coolant into the catch can vs. dumping it on the track like happened to you.

But this really works best when the cap is on the cool/low pressure side of the system like it is on most crossflow radiators.

When the cap is on the hot/high pressure side,you often need a higher rated cap just to keep coolant in the system under normal operating conditions.

I've often pondered if there was a hardware fix for this other than tapping for pipe plugs,but I have'nt come up with anything good yet,that deal would take some seriously creative thinking,and crafty engineering/fab work.

[stimpy]

the old fashion way, run straps across the tops of the plugs, drill machine screw size holes and tap the block for the strap to be held in place .

[Scott Roberts]

Just another example of screw in freeze plugs being safer , George!

[GOSFAST]

The core plugs in most builds should be "retained" for your own safety AND the safety of others running down the strip! This works both ways!

They can be "strapped", "pinned", or "bolted" in, but they should be done with some method. I've lost 2 cars over the years from the unexpected "water-loss". The drivers were lucky to survive as both were upstairs and both were 8 second rides!

We've been concentrating on this particular item for some years now and have sent numerous e-mails to NHRA (and others) to make this a "mandatory" safety issue in the rule books! To date, no responses!

We allow the customer to make the final decision as to whether or not they want this procedure done. After we explain the potential consequences, most opt in favor of it! This very small item COULD be a literal lifesaver in the end!

It's my understanding it IS mandatory with the "roundy-round" guy's?

I put a shot below of some "pinned". This is quick and easy and is done with all hand tools and some small roll pins! The very same pin kits sold to pin rocker studs!

The "straps" are also fine but most guy's don't appreciate the appearance, especially in the "street/strip" rides! The pins and cap screws however are barely visible when painted over!!

Thanks, Gary in N.Y.

P.S. Here's a very recent 620 HP, pump-gas, 406" SBC with the pins very visible. There are 2 pins per plug. Many we do with some 10-24 x 1/2" button-head cap screws, and "Loctite", where the core retaining wall thickness allows. Takes some add'l labor but well worth the time.

[Brian Baker]

"We've been concentrating on this particular item for some years now and have sent numerous e-mails to NHRA (and others) to make this a "mandatory" safety issue in the rule books! To date, no responses!"

It's likely going to take a racer getting killed before they'll ever consider implementing such a thing...and even then they might not consider it unless it's a high profile racer.

[GTOGEORGE]

Scott Roberts Quote: "Just another example of screw in freeze plugs being safer , George!"


OK, Scott that make 2 out of HOW many racers racing every weekend in the Country?



GTO George

[BruceWilkie]

Originally Posted by GTOGEORGE

Scott Roberts Quote: "Just another example of screw in freeze plugs being safer , George!"


OK, Scott that make 2 out of HOW many racers racing every weekend in the Country?



GTO George

George IMO that is just two we know about here on this board willing to say so. However I do know of several others that had core plugs pop but fortunately no disaster. Some I know about, the guys were embarrassed to admit the plug(s) popped because they felt they had somehow messed up. Others trash talked the builder.

I dont like pointing this out George, however you are quite vocal about guys racing stock blocks because they might blow and oil the track, yet not concerned that a cheap freeze plug could pop out of ANY motor using them seems contradictory. Oil or water under a car at most any speed can be quite dangerous.(especially with slick rear tires).

Gary has a valid point. I've always staked mine with a punch but I think a more positive retention method as he suggests is a "from now on" for me. Thanks Gary in NY.

(where in NY btw?)

[johnta1]

I've had more problems and know of more people having problems of Fram filters blowing out.
Why not outlaw them?

Never have seen a freeze plug blow out.
Seen a lot of rusted out plugs, though, on street cars.

[Exil]

Just a quick question, out of all the reported cases has it always been the plugs on the side or have other plugs come out also? Like the rear plugs in the bell housing area.

[PONTIAC DUDE]

Down here (roundy round) we put a spot of weld right at the lip of the hole and over the core plug on 4 sides.

No big deal on hammering in core plugs but if a block if offered with screw in plugs. Just a huge BONUS.

Sorta like the Boss 302 blocks of the 70's. Never understood why all aftermarket blocks don't offer them.

[Scott Roberts]

George,

I get where you are coming from. Kind of like guys with small pricks.................. They say size doesn't matter, its the motion of the ocean and all that crap. In this case, you are one of those guys. If your block had screw in plugs and the other didn't, you would be the biggest fan of screw in plugs! THEY ARE BETTER no matter how bad you want to put it down. Its okay to admit it!

[wrench]

I wonder what the cause actually is?? I have been a mechanic for almost 20 years now and have never seen a freeze plug just blow out. I have worked on and seen hundreds of cars with bad head gaskets pushing all kinds of pressure into the coolings system and never saw a plug blow out. This would make me think its just a defective (or the wrong size) plug? Of course a high horsepower engine at 8500 RPM is a little different than a street engine. If anyone here has had this failure, did you also find a bad head gasket or other issue allowing cylinder pressure into the cooling system? Just curious, I have screw in plugs, on the sides anyway.

[rcush]

Thanks for all of the responses, I have not had time to see if the head gasket actually did let go. I will check this weekend and let everyone know. I sprayed 200 and was at about 7000 rpm when it let go. I am running Felpro Blue gaskets so with what I was doing they definitely could have failed. There was no water in my overflow and I believe the Howe cap is a 16 lb cap. All the other plugs look fine so was it just bad luck? My engine builder competes in Engine Masters and I find it hard to believe they some how manged to put one wrong freeze plug in my block. He is very meticulous (anal) about everything he does.

I plan to buy a new block next year (Probably an IA2 with the screw in freeze plugs) but I would like to get out before the end of the year and make sure the car is straight and goes down the track okay. So back to my original question, what does everyone use to seal the freeze plug (sealant, adhesive, spit?).

Great discussion, which I had seen this before I said hello to the wall .

Bob

[84TA400]

Permatex 1A- I think that's what i use

[rcush]

84TA400,

Thanks, will look into the permatex product.

Bob

[mechanickeith]

I use green locktite!! (Sleeve & bearing retainer). Coat plug & block & drive them in!!

[GTOGEORGE]

Scott,
Motion of the Ocean...................?

I never said it was a BAD thing (screw in freeze plugs). Just saying if done correctly they ain't coming out, but like ANYTHING else, if not done right..............!

I would rather see EXTRA head bolts in the block..........STANDARD like the Aftermarket DROF small blocks.

Bruce,
I don't have a problem with people racing stock block Pontiac's, I have a problem with them spending Thousands & Thousands of dollars to ADD Horse Power and hardly ANY money in making them live longer (Blocks, Rods, Cranks) or proper safety equipment (Diapers, Roll Cages, Etc.) ! I mean would they strap there Family (Wife, Kids) members in their cars!


GTO George

[grnmnstr]

I had a block (IA2) drain plug back out on me at the 1/8 mile last year. Wasn't fun. I did a 180 into the other lane. Thank God I didn't hit anything.