View Full Version : WAAA! Leaking Engine Block!!!

01-08-2004, 10:24 PM
After fixing the heater pipe leak and refilling the radiator, I noticed a new drip coming from somewhere. With the help of a mirror and a torch I've found that the water is leaking from the engine block! It's coming from one of those round things - I think they're called welch plugs. It's the one near the rear of the block on the right (manifold) side, just above a nut that looks like it's a coolant drain plug.

So - is there something I can do about this without pulling the engine, or am I as royally screwed as I think I am? If I can't fix this myself I'm going to have to sell the car. graemlins/cryin.gif Anyone want a TC2500 going cheap?

01-08-2004, 10:42 PM
Pry it out and tap in a new one. I did this last winter on a 1500 Triumph engine. Easy and cost is probably less than a pint of Fosters.
[Edit: Chuck answered the question about 30 seconds before I did...and I agree: it's a small problem]

[ 01-08-2004: Message edited by: aeronca65t ]</p>

01-08-2004, 10:42 PM
Sounds to me it is a frost plug.If you have the space it is easy enough to do with out removing the engine.You may have to remove some of the parts to access it.Drain the antifreeze.Punch a hole in the plug and pry out.Clean the area good and tap the new one in nice and even.
Have fun and good luck.Hate to see a car sold for such a small reason,
graemlins/canpatriot.gif coolgleam.gif another suuny day

Mark Beiser
01-08-2004, 11:14 PM
If the access is to limited to get a good angle to get the new one in, but you can manage to get the old one out, most auto parts stors sell rubber plugs.

The rubber plug has a metal plate on each side of it with a bolt going through. You slip the plug in the hole and tighten the nut on the bolt. The metal plates sqeeze the rubber and it expands to hold it in place.

Only use the rubber plug if you cannot get the real thing to go in.

01-09-2004, 04:12 AM
Hello Wombat,
yes one name is Welch plug the more common, in the UK at least, is Core plug. Early ones are basically a domed disc of steel about 1\16" thick which was knocked in the middle of the dome with a drift which lodged it firmly in the hole. Your type is a disc with a lip all round giving a flat bottomed U section. You may be able to replace the leaking one without removing the manifolds but I would prefer to remove them as it is so much easier to ensure a good job. Then replace all the core plugs. If one has corroded then the rest will probably be in a similar condition. Drive a stout screwdriver or centre punch through the middle and twist to lever the old ones out. Thouroughly clean the block recesses then tap the new ones home with a flat bottomed drift using some gasket sealant to make sure they seal properly.

Alec graemlins/cheers.gif

01-11-2004, 02:15 AM
Thanks to you all for making it sound like it would be an easy job. You persuaded me to do it instead of selling the car.

Many, MANY frustrating hours later it's finally done. Yes I had to remove the manifolds, as the plug is behind the exhaust manifold and so the only way to get near it was to get them off. Getting them off was not easy. Those nuts inbetween the two manifolds are a pain, especially the one that's almost impossible to get a spanner to! While pulling the exhaust manifold off the exhaust pipe the pipe split, so I'll have to replace it. Oh well, it was probably about to go anyway. I had real trouble getting the old plug out, even with a really long lever. When it finally came unstuck it went with a bang and somehow I ended up with a hole in my hand. Even with so much stuff taken off the engine, there still wasn't much room to get a decent swing with the hammer, so it took an hour of tapping as hard as I could to get the new plug in. Putting the manifolds back on was easy, but putting the carbs back on wasn't - those **** linkages kept getting out of place.

Most days I really enjoy tinkering with cars. Today wasn't one of them. Neither was yesterday. Had I known how hard it was going to be, I wouldn't have bothered and I would have just sold it. But, thanks to you guys, I did bother, and I'm very pleased that I've still got the car. I just hope that it will run when I get the time (next weekend?) to try and get it started. Fingers crossed!

01-11-2004, 07:54 AM
Hello Wombat,

you may like to invest in a crows foot socket as this makes access to the manifold nuts easier. Also coat the studs in copperslip anti seize compound as it makes future removal easier.

Sorry this advice is given after you have done it but I would guess that it won't be the last time you will need to remove the manifolds.

Alec graemlins/cheers.gif

01-11-2004, 10:35 AM
Your ultimate triumph (pun intended) is the antithesis of your despair. Glad you stuck with it! Great story, I bleed with you.....
Been there, done that. I like the carry-on-regardless-attitude, that's what keeps LBC's on the road. Keep on truckin'.


01-11-2004, 12:14 PM
Well, I just noticed I have a similar problem on my spit! If I effect the same repair I have one question - is there someting I should coat the sides of the new plug with to help prevent future leak problems? All the suggestions I read here just indicate to punch in a new freeze plug, but it seems that a coat of maybe gasket cement or something similar might be useful. Thoughts? Also piman - what exactly is a crowsfoot socket?


Dave Russell
01-12-2004, 04:35 AM
You can see a crowsfoot wrench here;
I usually use a sealer on the plugs, something such as Permatex #80019 "Aviation-Form-A-Gasket" sealer.