The Stovebolt Site Forums The Shop Area Engine Shop Lower block drain.....

On our 235 lower block drain was replaced with a plug. The edges have been rounded off. It's a pain to get to lying on the floor with a 20"socket extension. Has anyone put their truck on a lift and tried heat to remove a plug like this from under the truck? It seems it would be much easier if so we will take it to a mechanic that has a lift. Also by heating the plug is the block in danger of being cracked or damaged from the heat? We will drain the anti-freeze out before attempting the plug removal. Who carries the correct drain cock...not Chinese produced if possible.
Thanks!

You should be able to get one at any plumbing supply place. Not getting a Chinese part...that might be difficult. Removing the old one? If you can get a good pair of vice grips on there you might try tapping with a hammer to get it moving. Go tighter, first then loose, rock it back and forth. Don't hit it hard, no reason to break it if you don't need to. If you use heat, use LP or MAPPS gas not Oxy/Acetylene. Heat the block not the plug. All else fails, drill it. Start small and work up to larger. Clean the threads with a pipe tap.

I had this problem with my 261. The machine shop put an allen plug there. I immediately stripped it out with no problem whatsoever.

I drilled it, then put an EZ out in the hole and it came out fine. THEN I proceeded to put a nice drain valve there. Now when I have machine work done on my engine block, I make sure to add that to my list of stuff I want done different.

Lots of good theories here- - - -now for some practical experience. Get the plug RED HOT with an acetylene torch, touch a wax candle or a block of parrafin to it (it will smoke, or possibly flame up) grab it with a pair of vise grips, and turn it out. I've removed a couple of hundred oil gallery plugs that way, and never had any problems with block damage at all. The plug has a 1/4" NPT thread, and after about half a turn the tapered thread gets very loose.
Jerry

All good ideas...but the main problem is space. Can't seem to fit anything in from the bottom on garage floor. The top leaning down is even worse. I will use a torch on the plug and then some wax but.....I think this has to be done on a lift. The plug would not budge with an impact wrench( due to the extension bars needed for the socket) when we tried vise grips just messed up the head and no room for a breaker bar. Has anyone tried this with the truck on those drive up ramps you purchase at FLAPS.....I wish I had a lift.
Thanks steve

How about removing the driver's side wheel, with a jack stand supporting the axle under the spring, then using a 6-point socket on a flex handle and some extensions from the wheel well? Once the plug is hot and lubed, it should turn right out with just a little effort. What size is the hex socket you're using? I have had some success with driving a slightly smaller metric socket over a rounded-off bolt head or nut, such as a 13 MM on a 9/16, etc.
Jerry

Everytime I see this come up on Active Topics, I think it says "Lower back pain."

Bend over one of those fat fenders awhile, and that's exactly what it means!
Jerry

Yeah, the problem with mine was it was in 'inny'. A correctly sized set screw. Took no time at all to round that allen hole. No matter really what you have, you can drill it out with about a 3/16 drill bit and the appropriate easy out. Sadly, I can see it happening OVER the fender faster than under. Back pain is a REAL consideration.

I have NO idea why a $3.50 cent water spicket wasn't put in by the engine shop in the first place. My engine shop owner tells me they never put a spicket in. Just a set screw with lots of Loctite. His response to why in the &%^&* don't you use a spicket is, not everyone wants it, so they make it easy for everybody! LOL! As a hobbyist, not knowing stuff, my reaction is, why would ANYONE not want to be able to drain their engine block? Oh well. We didn't need our backs for anything right?

I think it most certainly best to use heat before trying anything. Sometimes the position just sucks, life is like that so you can remember good from bad. Go slow and think first, good luck.

Hah! Good one Peggy

Dennis

Jerry,what does the candle wax do? Does is somehow get pulled into the threads? Guess the interfacial tension/capillary pressure caused by temperature difference between the plug and the block pulls it in? Have you tried it w/o the wax before?

Paraffin + very hot metal = instant thread release, for some reason. I don't know the exact physics or chemistry, but it has worked for me many times. Just heating the plugs will work, but adding the wax to the mix really makes a noticeable difference. I assume it gets wicked into the thread by capillary action of some type. I buy up the long tapered candles used for dinner parties when they go on sale at the big box stores. Particularly if they happen to be a little damaged, they're dirt cheap. As well as being useful for loosening tight bolts and pipe plugs, they're also useful as a stiffener for the cast bullet lube I make from wax sealing rings for toilets and automotive chassis grease. I cast and shoot a couple of thousand bullets a year, in 5 or 6 common handgun and rifle calibers.
Jerry

If the OP's plug was sealed with loc-tite, a little heat to the plug will melt the loc-tite, and it should come right out. I run into that stuff a lot with pressure washer pipe fittings. You cannot budge them cold. Add a little heat and they almost fall apart.
Carl

The magic number with most Loctite products is 450 degrees F. It liquefies, and the bond breaks. Heat is the only way to defeat the red stuff, and blue lets go a lot better if it's heated a little. If you're going to re-lock the thread after reassembly, do a thorough cleaning of the residue, either with a wire brush, or a chemical solvent, or both. It simply doesn't bond well to oily or dirty threads.
Jerry

I can't imagine using Loctite on a tapered pipe thread, that doesn't add up. I would only use a pipe dope type thread sealer.

OK...heat is the thing and wax also. Going over the top with my back is not an option plus doing that with an 02 torch in hand sounds like a bad idea. No response on trying a set of FLAPS drive up ramps. I probably need a set anyway so I'll pick some up. It seems it gives you a better angle to attack the plug with a torch. I'll have the wife stand by a couple with a of extinguishers. I'll drape a fire blanket over everything else. I have a pair of vise grips with a harden machined handle that will give leverage and I will use a slow rocking motion at just above a black heat......it all sounds like fun.....I hope the ramps are a good idea. If all else fails to the mechanic shop we go....agreed?
Thanks Steve

Get the plug hot first- - - -apply a little wax, and then lock the vise grips on. The "heat sink" action of clamping the cool pliers onto the plug will help shrink it by cooling it quickly. It takes a bit of coordination, but I think you'll be pleased with the results.

The drive on ramps are OK, but I still prefer a jack stand under the axle, and having that big wheel and tire out of the way while I'm trying to work under there.
Jerry

Hot rod....great idea......I'll jack up the truck as high as I can with my floor jack and us stands AND remove the front LH wheel. Do I jack the whole front end up by putting the jack under the straight axel in the middle or one side at a time? If I jack it up from the middle of the axel it would be less work. I'll be doing it on a nice concrete garage floor so we have a good base. Why do people put this type of plug in????? What a pain, at the same time I'll do heater core and hoses...I wonder what I'll find in the drain hole?????
Thanks Steve

Since you'll be working mostly under the driver's side, I'd suggest simply pulling the left front wheel and putting the jack stand under the spring pad on that side. I'm a little spooky about lifting a vehicle at the center of the front axle. I'm sure it's been done untold thousands of times, but there's always the possibility of putting a bend in it. Ditto for towing by wrapping a chain around the middle of the axle- - - -I've definitely seen some bent ones from doing that!
Jerry

Thanks very much for your comments Jerry! We always learn so much from you. You have a lot of valuable experience!

Thanks for the kind words- - - - -"experience" means I've learned a lot of expensive lessons by screwing things up frequently! Maybe I can prevent some of those mistakes on the part of others by sharing my experiences!

Jerry

Learned a long time ago that GM's policy concerning parts and what they used fell under the terminology "value engineering." In other words, why spend $3.50 when you can plug that hole with a metal plug that cost probably 2 cents back in the 40's. I think they are still using that policy. "The most cost effective quote from a vendor awarded that vendor the order."

What in the world are you talking about? Did you mean to post that reply on this thread? I am confused (easily, sometimes).
Carl