Anti Freeze Leak

**sconnors** · 08-20-2010, 02:27 PM

Discovered after my 1950 Buick Special is parked for awhile I notice a puddle of anti freeze under the car. It appears to be in the area of the transmission and although it doesn't seem to be leaking badly I want to fix it. The car is not overheating and doesn't seem to be going through a lot of anti freeze but there is definitely a leak.
I'm thinking it's either a freeze plug, or the hoses that run from the radiator to the transmission.
Anyone have the same issue or can point me in the right direction?
Thanks
Scott

**41buickcompoundcarb** · 08-21-2010, 04:46 AM

I had the same thing and found a freeze plug in the back of the head a couple inches from firewall .Be ready to change it if you reach your finger around the back of the head and touch it ,because as happen on mine it is so rusty it falls apart then really starts to flow . I replaced mine with a rubber bolt tighten style freeze plug from local parts master store .Good luck .

**41buickcompoundcarb** · 08-21-2010, 06:01 PM

Pm'ed message on fixe good luck .

**sconnors** · 08-21-2010, 06:12 PM

thanks man, i got your pm. i'll have to do some investigating...i'll keep you posted...

**sconnors** · 08-25-2010, 02:34 PM

Hi guys, I received this reply today from someone on another board. Please take a look and let me know your input:

The freeze plug on that block is on the back of the cam shaft and covered by the bellhousing. So when looking at the engine it's on the passenger side just below the cover that covers the push-rods.
An expansion plug won't work.. there is only about 3/8" space behind the freeze plug and then you have a turning cam shaft.

Pulling the trans and rear end is NOT easy on one of those, did one a few weeks ago and they are made to stay in the car.. The 3 crossmembers are all in the way, some thin paper gaskets between everything.. messy to say the least.

Drilling a hole in the firewall won't work, unless you are planning to also drill a hole in the bellhousing/clutch/pressure plate or torque converter.

Pulling the engine is a lot of work on one of those, because the engine is so long and heavy you pretty much need an a-frame, cherry picker won't handle it too well. And it's hard to do with the hood on.

So I guess what I'm saying, no matter what you decide to do, it's going to be hard. My advise (and yes I've done this before) is to pull the engine.
I've attached a picture of a bare block so you can see where the freeze plug is. Mine is still out (it was leaking ;-)

One more thing I forgot to mention.. This motor has a chicken/egg problem that's no fun to work around. This is true for a manual car, not sure about the automatic trans setup. You can't remove the bellhousing with the flywheel in place and you can't remove the flywheel with the bellhousing on the engine.

The flywheel has to come of first as there are bolts behind it that hold the bellhousing on. The only way to take the flywheel of is while it's attached to the crankshaft. So, you have to pull the crankshaft/flywheel assembly (2 man job!!) before you pull the bellhousing and can get to the plug.

Replacing that freeze plug requires you to take the whole engine apart.

Also, if you are leaking coolant it's not the freeze plug at the back of the engine, which only holds in engine oil.

**Straight Eight** · 08-25-2010, 04:25 PM

Just a minute, the hole in the block is only for the camshaft, and oil. There ain't no stinkin anti freeze in there.
The water soft plug is in the head, not the block. Can't you find it with a mirror?

**41buickcompoundcarb** · 08-25-2010, 06:17 PM

I am thinking the same thing , The one I had changed was the one in the back of the head .That can be seen with mirror and touched with fingers and get antifreeze on your finger tips . Try not to make a big project first , first find out what is leaking then figure out how to fix it .Good luck

**Long Roof** · 08-25-2010, 07:33 PM

Here is the back side of a 1953 263. There is a freeze plug about the size of a quarter in the rear of the head. Don't know if that helps or confuses the issue.

**41buickcompoundcarb** · 08-26-2010, 03:58 AM

That is the one I changed out .good luck

**sconnors** · 08-26-2010, 09:40 AM

Well guys I put the Buick up on ramps this morning. Wiped everything clean, spread newspapers underneath and let her sit. No leaks. Then I started her up and let her run for awhile and get up to temperature and then shut her off and watched for leaks. I think I found the leak! It appears to have been coming from a new frost plug that was put in. It seems that the nut on the end had loosened a bit and anti freeze was running down the block, onto the oil pan and dripping beneath the car. I've attached some pics.
Let's hope that's it!
Thanks for everyone's help and input it was as always greatly appreciated
You guys are the best
Scott