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Another jproblem I have had with petcocks in the past. The automotive ones I've seen are made like this one. A tapered pin closing on a tapered seat to seal. This makes it more than a little tough to stick the inevitable probe through the hole to knock debris out of the way for the block to drain. When this happens, you have to remove the whole petcock to clear the hole.
The pictured Mercury Marine plugs are good quality. Won't break and you can remove the center shutoff completely to get a probe in there. I've used this type for years on boats with no problems draining the block or manifolds. If boat plugs weren't so hard to get too, just a plain old brass plug would work fine.
I may have told this story before, but just to illustrate how bad it can get...
About 9 months after purchasing my '63 (in 1969) I decided it was time to freshen up the engine with new rings and of course add a few horsepower while I was at it. I pulled the (29k mile) engine and stripped it down to the bare block and took it outside to flush it out. What I discovered was that in an effort to deal with a leaking radiator, the original owner had used Bar's Leaks to stop the leak. The outboard water jacket was almost filled with 'brown' sludge, or Bar's Leaks as it is better known.
From the top of the water jacket at the back of the block to the bottom at the front it was almost solid Bar's Leaks. Clearly the rear cylinders were getting little, if any, cooling. That might also have explained why the rings were no longer doing their job and it was consuming so much oil.
I flipped this picture to better illustrate how bad it was. (this was not my actual engine)
Also, isn't this area prone to cracking? I remember when I had an engine built, one of the first areas the machine shop looked at for crack, was this drain plug area.
Also, isn't this area prone to cracking? I remember when I had an engine built, one of the first areas the machine shop looked at for crack, was this drain plug area.
They cracked horizontally above the plug due to freezing.
I can only tell you what work for my 63. I made a metal shield to surround the plug to keep the flame off the block and with a torch heated the plug to a dull red and then with a socket screwed it out. Vice grips would of worked if needed. And the block area around the plug was cool due to the trap water. With every engine I've had I remove the plugs and from the top flush out with water.
We owned our boat (freshwater only) from new, with a 350 SBC. It came with the brass petcocks in the 2 block drains. Every fall, I would go in and open those drains (we lived in Chicago area), and every year they needed to be punctured with a 1/16" diameter welding wire, to get the flow started....We did a lot of canal running, and picked up a lot of silt....
I have used the heat and vise grips technique to remove stubborn block drains before. Very effective. If I did not have an Oxy-Acy torch, the "weld on a larger nut" approach would be my next try. The heat from welding also helps. I had to use the "weld on the larger nut" approach to remove some wheel locking lug nuts last year, when I purchased a used car, after the dealer had lost the key (or was never given it).
I understand, and have no argument with the concerns about replacing the plugs with petcocks. But for MANY years, I've always gone back with petcocks in all my engines. When I change coolant, I also open and drain the petcocks and have never had any issues. And I also install them with antisieze------------------just in case I need to remove them. My next option would be to install a BRASS plug, NOT a steel one.
Also, when removing steel plugs from blocks, SO FAR (fingers crossed), I've always been able to break them loose with a 6-point socket-----------------although, some of them were scary at first, but finally broke loose.
What would help a lot is install a 45 degree elbow and then a plug. Anyone that has drain an engine before knows the water or freeze goes everywhere even on the starter. Only thing is it looks to hokey sticking out like it would.
Here with an update to this two year old thread.
My car started running a little hot and I really wanted to be able to pull both drain plugs for a complete flush.
I got the plug out today using this procedure:
1) Purchased an 9/16 EZ-out socket (or extractor socket) just like Robert61 posted in post #3
2) Blasted the plug head with a propane torch for about 30 seconds
3) Placed the extractor socket in place and hammered it onto the stripped plug head
4) Attached a breaker bar
5) Said a little prayer
6) Applied great force
And Voila! It turned! Not pretty, but it worked like a charm.
BTW: Frankie, I did try to use vice grips as you suggested.. but the angles are not kind. With the pan removed, it would probably work. But no dice with the pan on.
14mm and 9/16 are virtually the same. If you can and you still want it out give it a few good blows with a hammer. Not enough to knock the side out of the block but pretty good licks. Then some of the tool companies sell a female easy out that grabs rounded bolts. That would be your best shot at this point. Or you can leave well enough alone. Yours is no different than anyone else's. They are all stopped up at the bottom.
Originally Posted by SDVette
Here with an update to this two year old thread.
My car started running a little hot and I really wanted to be able to pull both drain plugs for a complete flush.
I got the plug out today using this procedure:
1) Purchased an 9/16 EZ-out socket (or extractor socket) just like Robert61 posted in post #3
2) Blasted the plug head with a propane torch for about 30 seconds
3) Placed the extractor socket in place and hammered it onto the stripped plug head
4) Attached a breaker bar
5) Said a little prayer
6) Applied great force
And Voila! It turned! Not pretty, but it worked like a charm.
BTW: Frankie, I did try to use vice grips as you suggested.. but the angles are not kind. With the pan removed, it would probably work. But no dice with the pan on.
Fred
Originally Posted by 59BlueSilver
Good job! Where did you get the extractor socket?
I would have given yours up for dead given the age of this thread, good job.
Now I'm going to go buy me some of those - never owned any. Sounds like an example of a one of a kind tool that you may never need, but if you do, you'll be glad you had it.
Not certain PB Blaster or Kroil will help you in this location.......but continue to use and hope.
I would use a Dremel or file and square things back up and get to fit a GOOD 6-pt 14 mm socket (Snap-on quality). 1/2 inch drive and use a 14-16 inch breaker bar.
If that doesn't work, I would probably just call it quits, rather than destroy things. One of our CF members tried drilling out the plug a few years back, but went in too deep and destroyed the motor (drilled into one of the cylinders)
A few clean water block flushes should probably hold you until the engine can be removed, and the plug removed with heat and/or machine tools.
Congrats on sticking with it and the results. Chase the threads with a tap before you reinstall whatever you decide to use. And make it brass. These plugs are extremely hard to remove even under the best circumstances. Often a drill is the only way.
Congrats on sticking with it and the results. Chase the threads with a tap before you reinstall whatever you decide to use. And make it brass. These plugs are extremely hard to remove even under the best circumstances. Often a drill is the only way.
And put some anti-seize compound on the threads. And only snug-tight.
The other plug (that I removed 2 years ago) came out fairly easy with this treatment.
...helped a neighbor remove the block drain plugs recently on his '77 Corvette. Left side came out okay, but the right side wouldn't co-operate. So I rigged up three 6" 3/8" extensions with a 6-pt socket and an adapter to a 1/2" breaker bar. This got the bar out from under the car (up on jackstands) so we could put some force on it... had the owner put some torque on the bar and I used a 2 x 4 wood block and a medium size hammer to give it a whack. The shock broke it loose.
Of course, no coolant came out, so we cleaned out the hole with dental curettes. We used new brass plugs with plenty of "pipe dope" on the threads and just tightened them "snug" - no more than 10 lb-ft... did a couple of water flushes (fill with water, start and fully warm up to thermostat opening) and finished the job with two gallons of Zerex G-05 and two gallons of distilled water.
The next time the job should be easier. If the above method with a conventional 6-pt socket won't work because the hex is rounded off, an extractor socket is the way to go using the same "shock" technique.
My 66 Coupe with a 68 small block had recessed steel plugs. One plug started to leak. It was clear that the machine shop that rebuilt the engine a few years ago did not change the plugs. I had to drill out the middle of the plug, tap it with a pipe tap and screw in a brass end plug. So far so good. Jerry
The best tool to get inside those holes is the stainless reinforcements on windshield wipers. They are strong, small and thin and can be bent into shape. Polking around will dislodge lots of crud. Polk a while and flush with water.
12-07-2017, 12:02 PM
