Side plate: what I found

[rigspelt]

In http://www.moyermarine.com/forums/showthread.php?t=2639 I posted a picture of the side plate before I started messing with wrenches. In taking off the ground wires connected to the top forward side plate bolt, I broke the head off that bolt, committing me to removing the plate. I kind of wanted to do that anyway, because there was no thermostat in the housing, making me wonder there had been cooling problems, and being on the hard for a general refit, now is the time.

I was worried about breaking off the two aft bolts, because there is no way I could get a drill in there to deal with broken bolts (bulkhead in the way). So with some anxiety I started from the front. The second bolt broke too, but thankfully the remaining six came out fine.

These photos show what I found. The engine was in fresh water for the first about 25 years, and salt for the last 9 or so. There is crud, but the jacket metal is in good shape. The diverter on the inside of the plate was covered in rust, with a restricted opening, but the inside passage of the brass hose T was remarkably clear. The diverter is somwhat corroded, but it was passing coolant through a hole in that rust pile. The lower photo shows the diverter after I scraped some of the rust.

In the upper photo, notice the rust around the head gasket seam ... hmm.

[High Hopes]

Rigsy,

The head is the probably the same. The manifold will be worse. Pop the freeze pulgs on the manifold if you really want to get grossed out. At least that is what I found.

I pulled my engine from the boat, cleaned the head and water jacket with garden hose nozzle pressure and a coat hanger wire. I had to replace the exhaust manifold. If you have the room, you can do this without removing the engine.

Good luck. Don's kit for water jacket studs works great. I replaced all of them.

Steve

[Kelly]

Would this not be the time to go with fresh water cooling? This is an added expense but when I opened up my block after decades of neglected maintenance, everything was remarkably clean. I thanked my lucky stars for whoever changed over to fresh water cooling/heat exchanger...

Kelly

[rigspelt]

Would this not be the time to go with fresh water cooling?

It's on the next order already. I may go with the Indigo kit, because I do not have room on the front of the engine for MMI's pump mounting solution.

[rigspelt]

The head is the probably the same. The manifold will be worse.

The exhaust on this boat was redone last year, but all they did then was replace the pipes from the engine to the muffler. The manifold was not cleared. The engine was "rebuilt" before it left the freshwater a decade ago, but no idea what that means.

1. Does taking the head off provide better access to the cooling jacket to clean it? That would not be enough reason to pull the head in itself. I do have corrosion along the head/block seam on one corner that may push me to remove the head anyway, though the advice so far is no need this year.

2. Similarly, does removing the manifold make it easier to clean out the manifold manually, or is it enough to remove the freeze plugs and aft exhaust water outlet then poke around?

3. How easy is it to reinstall new freeze plugs once they are removed?

[Marian Claire]

#1 Most defiantly. There are many passageways in the head and in the block to be cleaned. Most of my passageways were completely blocked and required a lot of work to clear them. Everything from drilling to hot high pressure washing.
#2 Same for the manifold. It is much easier to remove than the head.

This is based on my early model rebuild this spring. Enjoy Dan

[High Hopes]

Rigsy,

Yes to what Marian Claire said to 1 and 2.

3. I bought some neoprene ones at an auto parts store. They use a bolt to tighten and they squish out. They worked fine and looked pretty good, but I had a leak in the manifold and ended up buying a new manifold.

Steve

[rigspelt]

It looks worse in my photo in the first post than it really was. Once I cleared away the thin layer of crud that had piled up immediately behind the aft half of the side plate, I could see that the passages inside were not clogged significantly at all. This block is in great shape thanks to 25 years in freshwater prior to coming to the salt 9 years ago. Proof in the pudding.

I cleaned up as best I could in there, fixed the two broken bolts with a stud repair kit from MMI, and installed a new MMI side plate with their welded alternator bracket and new coolant distriubution cap. I decided I did not have reason to pull the head yet. I did removed the manifold and had it professionally cleaned and resurfaced by a machine shop: got some gunk out of the cooling passages there, but not a lot. I'll flush the block/head after I get the engine repainted and reassembled, and then hook up the new freshwater cooling system.

[High Hopes]

Awesome. Keep truckin' I almost wish was cleaning up another engine.