Hole in my head!

[ghaegele]

I was using a needle scaler to get the rust build up off my head when I noticed a hole. At first I was annoyed with myself thinking that the scaler was too aggressive, but I figure if it was that thin it was a problem waiting to happen.

I think I know the answer to the question, but is there a fix for this or am I buying a new head?

[Don Moyer]

We have seen quite a few heads that developed leaks right along the front of the raised area on which the alternator bracket mounts, presumably due to an anomaly during the casting process in that immediate area. If the head looks good otherwise, you might buy a bit of time by sealing the leak with one of the small fiberglass repair kits sold by West Marine. Take an ice pick and probe the ends of the affected area to be sure you cover the entire weak spot.

Don

[ghaegele]

Hmmm. Something like Marine Tex? How dependable is an epoxy patch? I'd hate for it to give out in the middle of a cruise, but then I had a Marine Tex patch on my water jacket cover for more than 3 years and only replaced it because the bracket finally failed.

[sastanley]

Yes...something like Marine Tex, however, I would go with something like West System. The P.O. of my boat loved the Marine Tex..I personally go with the West line, which allows me to control which additives I am using so they are best for that purpose.

[tenders]

For $250-350 for a proper solution I would want that problem out of my life forever. Let something ELSE get in the way of the enjoyment of your summer cruise!

Not so long ago, before Don changed the world of Atomic Four owners, you could spend all summer looking around for a decent replacement head.

http://www.moyermarine.com/cgi-bin/shopper.cgi?search=action&category=OVCM&keywords=all&template=Templates/B000_storebuilder.html

[CalebD]

I would think that something like JB Weld would be a better choice as it is made to resist high temperatures (check the label).
I would think that you could even use the regular epoxy thickeners in it and even embed some woven cloth with it in order to cover that hole.
HD or any decent hardware store sells it.
http://www.jbweld.net/products/jbweld.php

[charles@pricefarrington.c]

I would agree with Tenders, if you already have it off, why not put a new one on now.

I have a power boat with a straight six in it. I developed an exhaust manifold gasket leak in the San Juans last year and got some "mighty puddy" from West Marine, it's still working but, eventually it will blow again and I am planning on replacing it this year.

[ghaegele]

I also tend to agree with Tenders. But then I know how tenaciously Marine Tex and JB Weld hold to things that I can imagine the patch being the strongest spot in the whole head. Especially when you consider it will be going onto shop-cleaned bare metal and then painted. (I don't think heat is a problem as the head doesn't really get even close to their tolerance level.) And the list of things that also need replacement is nearly endless.

However, considering the purpose of pulling the engine and doing this all this work is confidence in performance, why return a worry to service? I will most likely side with caution and replace the head. But are there any long term experiences with an epoxy patch on the head or block?

[keelcooler]

A patch should work however consider it a temp fix at best.The hole you see in all likelihood is just the tip of your corrosion iceberg.If you patch do not lift the motor with the lifting ring, it could crack your patch. With your head off I would look for a replacement or be prepared to patch again.

[67c&ccorv]

You have come this far - time for a new head!

Next time, bead blast or hot tank only...needle scaler is far too powerful for a job like this.:eek:

[ghaegele]

I am positive that the needle scaler did not pierce the cast iron but merely removed already completely compromised metal. In fact, I am now convinced that I never had leaking studs (part of the reason I removed the engine) but rather it was leaking from this area and I assumed it was coming from the stud at the bracket. (A close inspection of a photo I took of the engine after I bench tested it before I took it apart shows wetness around and just under the alternator bracket right where this hole showed up.)

I used the needle scaler on my hand before touching the engine and was very satisfied that it was not agressive enough to damage the engine--at least not anywhere that wasn't ready to give out on it's own. If you look very closely at the photos of my head you can see a line in the metal leading to the hole. It appears that this was a defect in the casting that allowed rust to get in like plaque in the crevice of a tooth. I thought the needle scaler did a terrific job getting down to uncompromised metal and highly recommend it.

[Mark S]

Your engine is a late model, right? Do you happen to know the model year?

Mark S

[ghaegele]

It is a late model, I believe from the early 70s, if it's original to my C&C35 MkII, year 1974. Serial Number 190237. Anybody know how to find the year.

[ghaegele]

By the way, here's the photo evidence that this was a leak before I broke this engine down. I've zoomed in on a photo I took to document the pre rebuild condition. Watson, look just next to the alt bracket just under the #2 wire. Wetness!

[msmith10]

OK, so you need a new head. But those plugs might just clean up :D

[lat 64]

ghaegele,

your photo tells a real story. I took lots of photos during my tear down, and it was indispensable for the rebuild. After I studied the manual and went back to the pics I saw many problems that I didn't kept track of while doing the tear down. piston order, and proper placement comes to mind.

I see that you had washers under some too-small stud nuts on the head. I was told by ken(all-seeing MMI parts guy) that this not right. Something to do with not having the right suface area for the hold down force from the nuts. You might want to get the right ones anyway as yours look kinda porus:(

This seems to mean your engine has been apart for sure some time ago. I would be wary that it may not be assembled right, as these a-4s are a little different than auto motors. If the last guy to have it apart didn't know Atomics well, then he can make mistakes. I used to rebuild engines for a living and I had a lot to learn regarding this specific motor.

good luck, keep us posted,

russ

[ghaegele]

I was thinking of putting it back together with the washer spacer instead of the correct stud. No? Actually, that's my handywork: the washers were used because the stud itself was too long. When I replaced the head two years ago after a season-opening broken valve spring replacement, somehow I ended up one regular stud shy. I had an extra thermostat housing stud, so I used that with a dozen or so stainless washers figuring I'd replace the stud in short time.... Right.

All the rust is because of the leak I thought had from one of the studs. The salt water would collect in the spark plug well and boil off, sending caustic salt everywhere. And I have been snapping photos of all the stages of disassembly. Since I'm doing the work from weekend to weekend when I have the time I figure it will come in handy a month later when I'm scratching my head wondering how this goes back in.

By the way, as you can see, I have a lot of corroded bolts that I'd like to replace. I don't see them in the catalog. I could find them at a hardware store, but I hate the thought of putting cheep Chinese steel into good Wisconsin alloy. Is there a detailed source for hardware in the catalog?

[roadnsky]

Call Ken at MMI. He'll take care of you!
-j

[lat 64]

ghaegele,

I wasn't worried about the stack of washers. I figured you or somebody did a temporary repair. My boat is full of them:)
It's all the other nuts on the head studs. They are supposed to be a fatter nut called a "heavy hex" or something like that. Ken at MMI said this is important.

I had a deck leak and the same place on my engine got all rusty.

Dave Barry wrote a famous line: "water is bad for boats"

cheers,
Russ

[ghaegele]

Russ, I'm sure they're from MMI: Head nut - 3/8 by 9/16 hex head fine thread. I replaced them all 2 years ago. (Yeah, I know. They don't look like it.) And I've had an A4 in my boat since I was a teenager and never remember a different nut on the head. (BTW, I like that: Water is bad for boats!)

[Dromo]

The two 3/8 by 9/16 nuts you are showing are for the two thermostat housing studs, all the other nuts for the head are 3/8 by 11/16 .

The 3 nuts on the manifold should be 3/8 by 11/16 also.

In total you should have 18 -11/16 nuts, counting the 3 for the manifold and 2 - 7/16 nuts for the thermostat housing.

You also might want to look into finding someone that does metal stitching, in regards to repairing your head. Ask a machine shop if they can refer you to someone with experience in the field.

Here is a link www.locknstitch.com check out some the repair using this process. I don't know if it would be cost effective for you but it worked for me

cheers Rick

[ghaegele]

Rick, I thought about metal stitching the head but you need 3 or 4 threads good in the material you're stitching and the defect I've got doesn't give that much material to stitch into. I'm resigned to replacing with a used head from MMI. Just don't need the splitting head-ache of an in cruise blow-out. (Pun intended)

I never realized my head nuts were undersized. I have the larger nuts on the manifold but replaced the head nuts with the same sized ones that had been on the head of every other A4 I've seen, the ones MMI lists as "head nuts." But now I see they list both as "head nuts." Sure don't mind something bigger holding down the head and will definitely use the larger size when replacing. Thanks for the heads-up. (That one wasn't intended.) Do they use washers?

[Dromo]

no washers with the 11/16 nut
Rick