slow leak under alt bracket

[Marty Levenson]

hello experienced A 4ers,

Since reinstalling my old a4, one head bolt has been leaking water slightly and intermittently....when she is about half way warmed up. It comes from under the alt bracket, puddles around one spark plug, and boils away pretty fast.

I am worried it will increase suddenly. Afraid to tighten or mess around with it: these bolts have not been touched since 1967 and I can imagine my sailing season going bye-bye if I start trying to remove and reseal.

A boat mechanic I know, and mostly trust, suggests adding a goop to the cooling water that slowly finds and fills holes and cracks. I don't yet know the product name, but he says Canadian Tire sells a variety that are for different types of metal. My main fear of trying such a product is that it could clog up my shiny new Indigo heat exchanger. He claims it will not harm the exchanger.

Has anyone tried such a product? Am I better of just watching how it develops?

Thanks,

Marty

[Mo]

Hi Marty,
Go ahead and buy some high heat permatex and do the job. You may be surprised how easy it may come out. A few tips:
-if the nut comes off easy grab the stud with a "NEW" vice grip with good teeth...old ones just make a mess.
-clamp on the vice grip a tightly as you can and twist gently. 1/8 inch back and forth gently...you are breaking it away from rust and don't want to twist it off. Continue doing this until its spinning freely and removes. Another thing you could try, if you have the room, is double nut and lock the nuts together and try to back it out....again, small movements back and forth until it's loose.
-at this point I'd purchase a new stud and nut.
-place permatex around the stud and put it back in...snug it up pretty good...then put the bracket and nut back on and tighten to specific torque.
-I'd let it all set up overnight before firing up the engine and it should be OK.

There won't be enough of anything there to interfere with your heat exchanger.

[Dave Neptune]

Seal it

Marty, I'd do as Mo suggested however I would recommend Permatex #2 and not to use a silicone base sealants on old parts! I like the aviation grade for almost everything however the #2 is a bit better for the studs especially in an old engine!
Once you have the studs out or exposed it's not a bad job at all. You will need to drain a bit of water out of the block so you can reinstall the studs in a dry condition.
Note~~when I installed my "alt bracket I even put a small "smear~bead" around the stud holes on the bracket so that it was sealed to. It also helps hold it in place and no leaks into the plugs.

Dave Neptune

[roadnsky]

... Afraid to tighten or mess around with it: these bolts have not been touched since 1967 and I can imagine my sailing season going bye-bye if I start trying to remove and reseal.

A boat mechanic I know, and mostly trust, suggests adding a goop to the cooling water that slowly finds and fills holes and cracks...

Has anyone tried such a product? Am I better of just watching how it develops?

Marty-
What the boys are suggesting is the proper way to go for the repair.
I think they missed your original question regarding ADDING the goop INTO your cooling system. I'm gonna warn you against doing that.
At best, it's a stop-gap and at worst it'll cause you a lot bigger issues downstream.

If I read your post correctly, what you'd like to do is sail the season and THEN do a fix?
I think as long as you keep a wary eye on that leak you could get away with it.
Worst case, you see it's starting to leak more and you bite the bullet and do the task.

That being said, the project is not that big. It SHOULD be only a one day task.
But, in my past experience, once you head down the rabbit hole, it can be easy to get lost in there and find other issues that make a small project bigger.

Howz that for wishy-washy advice?

[edwardc]

As a stopgap, you could remove the nuts from the two studs that hold the alt bracket, put a bead of permatex around each stud, replace the bracket and retorque. This should control your leak till the end of the season when you can do a proper repair.

If you let the water pool & boil around the spark plug all season, it will corrode the base of the plug. Let that go on too long and the plug will become very hard to remove.

[marthur]

I like what Edward suggests and will add one thing. Clean the stud that shows above the nut VERY thoroughly. Especially get any rust or corrosion with a wire brush. Lubricate it well.

If you don't do this, you might end up taking the stud out whether you want to or not. Or (heaven forbid) breaking it. This is the voice of experience speaking.

Here is another thought: if you are monitoring it until the end of the season, you could also replace your spark plug several times to prevent corrosion from freezing it in place. You wouldn't even need to buy a new one. Use your wire brush to shine it up and reinstall.

[thatch]

Another approach

Marty, Assumming that the heat exchanger fill cap is at the highest point in your system, you might try loostening it during your next warm-up which may stop the coolant from being forced out at those head studs Remember, the primery reason for pressurizing the coolant is to increase its boiling point, which is normally not necessary on most of our A4's. On my personal HX I use a non pressurized, "vented" cap that creates zero pressure on that side of the system. My normal warm-up procedure involves removing the cap to check for flow and coolant level. In a vented system like mine which does not use a coolant recovery bottle, the coolant level will be slightly down from full but will rise to full as the engine warms up.
Tom

[Al Schober]

Marty,
Been hesitant to reply on this issue - what if it were my boat? What would I do? (I also have a HX).
Certainly not fool with the stud at this time in the boating year! Suggestion to go with a 0 psi system is good - we certainly don't need a pressurized system. Remove the bracket and seal between stud and head? Certainly easy to do, but I think I'd use silicone, put on a decent bead, let it set up, then reinstall the bracket and torque to spec. Doubt if it will get worse - might even get better???
Let us know how you make out.

[Marty Levenson]

options...options....

Wow - so many options I never considered. That's why i like this forum so much.

My thinking at the moment is to try and manage my way through the problem all summer, and then tackle the root of the problem end of Sept. The proper fix can be easy, but after my multi-month fiasco (see "Bowen Island Paint Job" thread) I know how this can go sideways fast.

For sure I will try the zero psi idea: that makes a lot of sense to me. Thanks too for the heads up about the potential spark plug issue: for sure I will keep that plug shiny. If the leak gets worse, I'll see if I can get those two nuts off, remove the alt bracket, and seal between the nut and the top of the head. Al: curious why you suggest silicone? Also, if I went that route would I need a certain type of silicone.

Many thanks for the great replies....they really opened some new ways to approach the problem. And yes, no goop in the coolant....I had a bad feeling about that!

[67c&ccorv]

hello experienced A 4ers,

Since reinstalling my old a4, one head bolt has been leaking water slightly and intermittently....when she is about half way warmed up. It comes from under the alt bracket, puddles around one spark plug, and boils away pretty fast.

I am worried it will increase suddenly. Afraid to tighten or mess around with it: these bolts have not been touched since 1967 and I can imagine my sailing season going bye-bye if I start trying to remove and reseal.

A boat mechanic I know, and mostly trust, suggests adding a goop to the cooling water that slowly finds and fills holes and cracks. I don't yet know the product name, but he says Canadian Tire sells a variety that are for different types of metal. My main fear of trying such a product is that it could clog up my shiny new Indigo heat exchanger. He claims it will not harm the exchanger.

Has anyone tried such a product? Am I better of just watching how it develops?

Thanks,

Marty

Would this be the same alternator bracket that you used to lift the engine out of the vessel?

[Marty Levenson]

alt bracket

"Would this be the same alternator bracket that you used to lift the engine out of the vessel?"

Hah: I was waiting for that one. Yes! ...and I have been wondering if that is the cause....

[Marty Levenson]

lifting

there were straps under the pan as well, but there was one point in the installing that it was supported only by the alt bracket.....

[67c&ccorv]

I know the designers felt it was OK to lift the engine by this method - and others on the forum agree...

...I'll be the odd man out on this issue and say the lifting eye was a good idea but a bad design.

That's why I will sling my engine when it comes time to remove or install it.

[ndutton]

My unfounded opinion is the lifting eye was perfectly fine for new engines. Every engine I installed, every engine I saw installed and likely every one of 40,000 engines were lifted into the boat that way without consequence.

Forty years later with a lifetime of raw water cooling running through the head and the internal material loss to rust that comes with RWC, the lifting eye - and its off center leveraging force under load - is now bearing on a deteriorated (thinner) head casting. That's where I think the problem lies.

[67c&ccorv]

My unfounded opinion is the lifting eye was perfectly fine for new engines. Every engine I installed, every engine I saw installed and likely every one of 40,000 engines were lifted into the boat that way without consequence.

Forty years later with a lifetime of raw water cooling running through the head and the internal material loss to rust that comes with RWC, the lifting eye - and its off center leveraging force under load - is now bearing on a deteriorated (thinner) head casting. That's where I think the problem lies.

“Give me a place to stand and with a lever I will move the whole world.”

Archimedes.


That rascally old devil still lurks in the lifting eye of the Atomic 4!