Water jacket questions

[geekeasy]

1. Am I correct that the area the water flows through is called the water jacket? I'm assuming that based on its cover being called the water jacket cover.

2. Now that I've got it open any advice on cleaning it?

3. Any advice on protecting it. High temp primer or something?

4. What's the bolt or screw in the lower left of the pic? Is it a drain for the water jacket?

Thanks!

[sdemore]

I'm new to all of this Kiki, having just rebuilt my first A4, but I'll give it a shot and let the others correct me.

Yes, it is a water jacket. A water jacket is just a water filled cooling chamber.

Personally, I would mechanically clean it first, scraping and brushing out as much as you can, then soaking in muriatic acid to really clean it.

Protecting it is done by installing a fresh water cooling system to keep it from corroding away again. I don't think there is anything that you could coat it with that would both protect it and allow heat to flow away from the pistons and head.

That bolt is a drain. Mine had a piece of brass tubing about 6" long in it, with a cap on the end.

Hope this helps and we'll see how many corrections I get.

[Dave Neptune]

Kiki, I had E-35 #136 for 35 years~great boat.

The inside does not look all that bad. If you have the head off you can use a small "fraid" cable or a "bent" coat hanger in a drill motor and chip away. Just knock the loose stuff off and vacuum out the water jacket. I did this once a long long time ago.

The best cure for corrosion is to go FWC which is a bit of an issue if your engine is under the settee as there is not much room for a front mount water pump. The Indigo mount on the alt/accy drive works OK too.

I would not bother with an acid flush once "routed out" however a possible vinegar soak may help after reassembly.

If indeed the head is off check the head passages too.

Also do a good job on sealing the cover and the MMI kit works wonders here!!

The diverter mounted to the side plate is of the utmost importance for proper circulation and cooling. Very important.

Dave Neptune

[Al Schober]

Kiki,
You've got some pretty heavy corrosion there - both inside and outside. Fortunately, it doesn't take much iron to make a lot of corrosion. Removing the corrosion takes work, but there are some tools that work well. First is an angle grinder with a heavy duty wire wheel - looks like a bunch of twisted wire ropes. The other tool is a needle gun - check out Harbor Freight. Needs a good air compressor. Oh yes, safety glasses with side shields or a full face mask - otherwise you're going to add an opthalmic surgeon to your list of friends.
Flushing the block is MUCH easier if its out of the boat - just fire up the pressure washer!
Corrosion inside the block tends to block off the passages between the head and the block - particularly those over on the valve side of the block. To do things right, you should remove the head and clean them out. (Good time for a valve job.)
Yes, that plug lower left is a drain. There's another lower right behind the starter. You might need a drill bit to cut through the deposits and get them flowing.
Strongly recommend you change to studs and nuts to secure the cover plate. Doing this will eliminate 8 leaks and prevent future corrosion on the stbd side of the block.
Before you paint the block, use a good primer - a rattle can is a waste of time. Personally, I prime with Interlux Interprotect 2000E - a 2 part epoxy primer & waterproofer meant for underwater metals. It's messy to work with in small quantities, but gives fine results. A couple of coats of that and you're ready for top coat - your choice. Top coat is just for gloss and color.
Strongly recommend going to glycol cooling - prevent all that internal corrosion and future winterizing issues. Do a flush with muriatic acid to get the inside clean. Flush solution should be about 5% - how much to dilute depends on the concentration in the jug - jug acid is usually 20%.
Hope this helps..

[BunnyPlanet169]

Kiki: Looking at your block, I'm more concerned about the exterior corrosion than what I see inside. The inside looks pretty good, and some gentle rooting around is sufficient. Vacuum the bits out, don't run them through the head.

The castings are not so thick, especially around the cylinders themselves. Don't bang around inside too much. I would be more careful to first do no harm than I would be to get it down to bare metal.

Wire wheels (exterior only) will do what you want. They come in different shapes and sizes, get a 4"-6" one with the wires coming out radially, and another two with cup shaped wheels where the wires come out the front. One of the cups should be essentially filled with wire - you can get into pretty tight corners.

Your jacket threads look pretty good, and if not, MMI has a kit to put a couple studs in. I did something similar, and put studs in every hole. Your sealing surface looks like it will clean up well with a putty knife. You can then clean it up with some 220 sandpaper and a block of wood. The block of wood should be big enough to touch both the lower and upper surfaces - keeps things flat. Keep it as flat as you can, but with a gasket and gasket compound you can make up for a lot of scratches.

If you have a chance to take the head off, it would be a great time to root into it as well - but without seeing the big picture I would again say first do no harm. Often you take something apart on a 40 year old engine and it becomes broken. If you don't pop the head,then a vinegar soak and flush is probably a good idea.

So you feel better - this is what a horrible block looks like:

http://www.moyermarine.com/forums/album.php?albumid=150&pictureid=1552

[Al Schober]

Boy, THAT'S an ugly block!

[BunnyPlanet169]

Boy, THAT'S an ugly block!

Like I said, Kiki's looks pretty good to me! But I've been traumatized, no doubt.

[geekeasy]

Thanks for the advice everyone.

As for the status of the engine, the starboard side had substantial corrosion. What you're seeing here has been somewhat cleaned up. Any lose metal has been removed, and the any remaining paint removed with paint stripper.

The port side and inside is relatively very clean.

[geekeasy]

Pic of the other side.

I've also started stripping th paint from this side in preparation of painting.