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Water Leaking - Heater core and core plug

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AUSMHLY

AUSMHLY

Yoda
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I have water leaking, a fast drip, from two places. 1)under the dash and 2) engine core plug.

The car has been sitting for 19 months in body shops. It was running fine when I dropped it off at the body shop. Then when I started it, the leaks happened. Anyone tell me why these two leaks happened after sitting for 19 months?

#1 seems to be coming from the heater. I looked up there and can not see where the actual leak is. It drips somewhere from the area on top of the heater I think?

What plan of action do I need to take. Remove the heater? If so, what do I need to do first. Any advise would help before I start doing a lot of removing of things I may not have to.

#2, is a leak coming from one of the core plugs in the engine. The one on the left side, above where the exhaust attaches to the manifold. Residue of the leak on the engine looks kind of rusty too. Should I have concern? How do I remove that plug and replace it? I seem to be getting a lot of parts from Moss. Anyone know the part number I should order?
Thank you, Roger
 
Replace it with brass core plug,I got all of mine from the local NAPA store. Be sure to use some permatex on the flat sealing area of the plug. Skip
 
[ QUOTE ]
I have water leaking, a fast drip, from two places. 1)under the dash and 2) engine core plug.

The car has been sitting for 19 months in body shops. It was running fine when I dropped it off at the body shop. Then when I started it, the leaks happened. Anyone tell me why these two leaks happened after sitting for 19 months?

#1 seems to be coming from the heater. I looked up there and can not see where the actual leak is. It drips somewhere from the area on top of the heater I think?

What plan of action do I need to take. Remove the heater? If so, what do I need to do first. Any advise would help before I start doing a lot of removing of things I may not have to.

#2, is a leak coming from one of the core plugs in the engine. The one on the left side, above where the exhaust attaches to the manifold. Residue of the leak on the engine looks kind of rusty too. Should I have concern? How do I remove that plug and replace it? I seem to be getting a lot of parts from Moss. Anyone know the part number I should order?
Thank you, Roger

[/ QUOTE ]

Well lets see Roger. Those items are probably normal fatalalities for a 40 year old Healey.

First action I suggest is to remove the TACH so you can see whats UP! wid the heater assembly. There are two possibilities for a failure in the heater assembly.1] The diaphram in the heater contol valve located on top of the heater assembly has perished. 2] the matrix of the heater unit has rotted out.The heater valve can be replaced without removing the heater assy it is a bit of a chore, but so is removing the heater.However, if the problem is the matrix the heater assy will have to be removed and the matrix either repaired at a radiator shop or replaced with new.

The core plugs as has been sugested will require replacement with new brass ones. Once the leaks are corrected the cooling system should be cleaned out ,flushed and fresh antifreeze/water installed---Hope this helps---Keoke
 
Keoke, as usuall, your spot on. I removed the heater to find the leak was coming from the control valve. I'm adding that part to my list. The Matrix seems to be cracking/separating at both ends, so that will go off to a radiator shop Monday.

Seems only one core plug is bad. So bad that it now gushes out in a flow. If counting from the front of the engine going back, it's the 3rd plug.

I have not taken it out yet, for I spent yesterday buying 4 jack stands, a jack and a creaper. Now that I can see where all 4 plugs are, I'm concerned that maybe the others are bad also. I know not if they are brass, or steel, but there sure is a lot of rust/sludge coming out of that one plug.

People have told me to replace all four. Also, replace the water pump, and thermostate at the same time. What do you think?

I know I will have to remove the exhaust from the headers to have room to remove and press that plug in. Will I have to remove anything else, to get to the other 3 plugs?

Just throwing this out, but I was told from the PO that the engine, radiator, trans were all rebuilt about 1000 miles ago. It's been sitting in body shops for 19 months. I didn't see this problem, I mean adventure, coming. Not that I see any of them.

So, do I play it safe and replace anything associated with water? The radiator looks fine I'm told. Anything else I should be aware of, look into?
Cheers, Roger
 
I had some leaky plugs in some inaccessable places. There was enough room that I managed to get the old plugs, out but not enough room to drive the new ones in. I used expanable rubber plugs and they worked fine. I think they will last as log as the original plugs.
 
As already said above, when you take out the core plugs, flush and flush and poke about. Amazing amount of crap should come out
 
You might check with the PO about that engine rebuild, as to just what was done. If it was a total rebuild, main and rod bearings, rings, maybe pistons and cylinder bore, the machine shop would have put in new plugs. They would have cleaned, flushed the block pretty good. Maybe the rebuild was only to the top end, ie. valve, seats, rocker arm, etc.
 
Sorry Rodger, I did not get back to the forum earlier.
However,Richard Dickinsons suggestion should be given some considertion as an easy short term solution.Reportedly, these plugs work very well.If you decide to replace the plug then I am of the opinion that they should all be done.Contrastingly, I would leave the waterpump alone at this time if it is not leaking and the thermostat too if the engine is not overheating.Shorn's assessment of the core problem agrees with mine.However, you will be required to drop the Manifold system to do the total job correctly and that can be put off until a later time using the Rubber plug. Hope this Helps---Keoke
 
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