MOXIE62

I would like to drain all the water that is in the radiator and engine. Of course there is the valve at the bottom of the radiator but that will not get rid of the water in the engine. The two pipe plugs at bottom of engine are frozen up so I'm afraid I will break them off if I use to much force. Can I just remove one of the head bolts from the rear of the engine, stick a hose in the hole and siphon out the fluid. What do you think.

corvettekent

No.

Gary's '66

My plugs were also rusted solid after the car sat for 15 years. Spray some penetrating oil like PB Blaster on them. Do it more than once and wait a few days. Wipe off any excess then heat the area around them using a torch. Use a 6 point socket and long bar and they should break loose.

Gary

BB767

Patience is your best friend in this case. As Gary suggested use a six point socket and penetrating oil, adding more oil every few hours. Take a scribe or an awl and remove rust and crud periodically from around where the plug threads meet the block. That will allow more penetrating oil to migrate along the threads into the block. It might take a week or more but if you're patient enough and keep oiling them up, they eventually will break loose.....unless the plug heads are so badly rusted that you can't get a good bite on it with the socket.

Replace them with hex headed brass plugs (1/4" pipe thread I believe) and use pipe dope on them when reinstalling them. They don't have to be crazy tight, just enough to seal the drain hole. Good luck.

Thomas

Pierre

After you remove the steel plugs, replace them with petcock valves, same as you should have on your radiator. Make it lot easier to drain the engine next time.

biggd

Remove the T-stat and reinstall housing with no T-stat. Remove lower radiator from the water pump and top hose from the radiator. Hook up the exhaust end of your wet vac to the top radiator hose and turn it on.Flush with clean water and do it again, maybe multiple times. You may have to do the heater core after with a garden hose. The radiator you can just flush with a garden hose. If the system is rusty then you may want to run some cooling flush in the system before flushing.

Gary's '66

Unless it's a C2. I put petcocks on my car shortly after I got it and was finally able to remove the plugs. Then I had some starter grind and realized I was missing the front (to the car) starter support bracket. Now, after replacing the bracket I can't open the p/s petcock w/o removing that bracket first! You can bet that I'm going back to the plugs on the next flush.

Gary

MOXIE62

I used some heat and was able to get the plugs out. I can not put in the little valves as the spark plug wire shield is in the way.

AZDoug

If you can't get the block drain plugs out (doubtful you can), take off the water pump and jack up the back of the car about 18".


Then run fresh water through the block from a garden hose, that will displace all the remaining coolant, but leave some water in the block.

The little bit of dissolved minerals in the hose water won't hurt anything.

Once back together , add six qts of AF,and fill the remainder with distilled water.

edit: you can probably leave the WP on,and just take off the lower rad hose and get the same effect.

Thius is something you want to do outside,a nd be sure and flush the AF well into teh lawn, or someplace where an animal won't drink it.

Doug

MOXIE62

I was a little leery of putting heat on the plugs for fear it may damage the block. And too, with water still in the engine I did not think the plug would heat up. I decided to try it anyway and pointed my acetylene torch right at the plug. I put a shield at the oil pan where it comes in contact with the block to keep the flame off the gasket. Got the plugs cherry red and still took a bit of force but both of them came right out. And to my surprise the area around the plugs were not hot at all or the paint damaged. Seems like the water that was in the block kept the block cool.

Gary's '66

See, I knew it would work! When all else fails, heat is your friend. Now you can do the job right and easily drain the block without removing the water pump, siphoning, turning the car upside down or sucking it out with a straw.

Gary

schmibm

Are you just wanting to clean everything out good? Is this why your mission to remove all the water? Or are you doing this for another reason? If cleaning, have you tried any cleaners in the system yet? Plain white vinegar works very well and won't hurt the system. It will help remove rust and hard water scale. You just want to flush plenty to get the ph back to neutral.

split1963

is Vinegar ok for Aluminum radiators?

tbarb

Good Job,

Go back with steel plugs like original after you run a tap through the threads to clean them up. Use some permatex #2 sealant on the plug threads and just snug them.

You will not have any more problems.

JohnZ

I'd recommend using a thread-chaser, not a tap - a tap will remove metal, and you don't want to do that.

ghostrider20

Plenty of good advice. I have had good luck just flushing as mentioned above with the T-Stat removed. Or, just drain and refill with distilled water and drive for 30 min. Then dump the fluid from radiator, and repeat. Do this 4-5 times and you have pretty much got it all.

With this method, you will have water in the system that you cannot remove. I just add a gallon of pure antifreeze, then a 50/50 mix after that to top off.

Lots of ways to skin this cat.

- Mark

pop23235

+1 on the thread chaser idea, plus this is a good place for anti-seize.

schmibm

Vinegar is no issue for an aluminum radiator. I have done it many times. There are many radiator flush cleaners out there that do the same thing. They all say compatible with aluminum radiators. About 100% of all today's vehicles are aluminum radiators.

56early

One of the most effective ways of purging and filling a cooling system I have found with out all the threating harm of making a quick job a nightmare is using this tool UView 550000 airlift.

TCracingCA

And i will continue to share my unique tricks to help my fellow Corvette guys!

Tip the engine upside down!