Newbie Questions Restoring 1957 Johnson 18hp FDE-11

[Mumbles]

Just a side note, but the Permatex 51531 Flange Sealant and 51813 Gasket Maker only require the 24163 activator if the motor is going to be used the same day it is being assembled. Otherwise letting it sit for a day or two before starting will allow enough time for the anaerobic sealer to set. Besides, every spray can I’ve had of the 24163 seems to leave more of the product on my hands and the floor than on the area I’m trying to spray. I’ve contacted Permatex about their faulty spray can design but have never heard back from them.

It’s also a good idea to check and record the alignment of the rod and cap before disassembling them so they can be reassembled the same way. This is done by dragging a dental pick across the filed or machined edges of the outer rod/cap joint. Newer style rods have four edges (the outer corners) to check on each rod and require at least three of them to be aligned to be satisfactory. Any overhang or misalignment of the cap will be a misalignment of the bearings surface.

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[jimmy]

Well, I’ve already disassembled the rods and end caps. I did mark them with a sharpie, but hadn’t read that the alignment was so critical. I figured they put these together by hand, so they must line up pretty easily. Is there anything I can do to get them lined up and marked, so they will not be a problem?

So, right now the crankcase is open and pistons are out. I have a new crank and pistons lined up, I’m in a holding pattern until a local member can help me get the cylinders honed, which may be a week or two away. Is there anything I should do to clean up and or protect the crankcase surfaces? Should I clean up the exhaust ports?

I do have all new gaskets and seals to put it back together.

[jeff-register]

Jim,
What are you going to use for block to crankcase sealer?

[jimmy]

quote Jeff Register:

Jim,
What are you going to use for block to crankcase sealer?

That’s a good question. Looks like there are several options, I’m new at this so I’m not sure what the requirements are.

[jeff-register]

Jim,
Kind of felt that, Just trying to help. These mtrs run well to factory specs. What Mumbles said 2,

[chris-p]

Good to know Mumbles.

Ive always just used the Loctite 515 as it is what works for me. Im pretty sure it is likely the exact same thing as in the Permatex tube!

Jimmy, if you marked them you are good. Put the cap back on the correct rod, in the same orientation, then finger tighten the caps. Rock them with your finger as you tighten them down you you will almost feel them drop into place. Then, as Mumbles stated, use a toothpick or your fingernail and run it along the seam to ensure it is smooth before torqueing down cap bolts.

[jimmy]

Hi Chris,

Sounds like I have a few options, and the local auto parts stores carry Locktite and Permatex. My plan is to rebuild the powerhead, and get it all back together, and then prep it for paint. Since I won’t be starting it up anytime soon, do I need the prep/primer/activator? Or is this cheap insurance to make sure I get a good seal?

My new crank, pistons, and wrist pin bearings are on the way. I guess Christmas is coming early.

[frankr]

Once upon a long time ago, I attended a class given by Locktite, telling us about their products. I remember they told us that the anaerobic sealants require a catalyst to make them set up and cure (in addition to lack of oxygen). The catalyst is the metal that they are in contact with. They cure very quickly in the presence of brass or copper. Considerably slower with aluminum. Very slow if at all with stainless steel. Not at all with plastic. That’s why the cap doesn’t seize on the plastic tube. However put some primer (catalyst) on that cap and see what happens. I suspect the primer has some sort of copper material in it.

All that to say that the aluminum – to – aluminum joint will cure slowly, and possibly unreliably. Put the primer (catalyst) on it and it will cure quickly and every time. When I was making the timing fixtures (now made by Richard White) I used Locktite to fixture the aluminum top bar to the aluminum center hub until I got them drilled and screwed together. Without primer, they cured over a long time, but with primer just about 10 minutes or so.

BTW, concerning the spray can. They also make that stuff in a bottle with a little brush in the cap. One of those little bottles will outlast a whole bunch of spray cans

[jerry-ahrens]

I’ve always used the primer when using the gel seal, or any of the anaerobic sealer. You can actually order that stuff in a kit form, that comes with a smaller tube of the sealer and a small can of primer. I’ve always got that through Mercury Marine, but I’m sure other places have it. The surfaces must be absolutely clean before applying this product…. no grease, oil etc.
I’ll get shot at for this, but I’ve always used the old school 3m 847 for the crankcase halves of these old engines. But I always use the anaerobic stuff on modern motors.

[seakaye12]

quote Jerry Ahrens:

Why is that Jerry? Why do you suppose it works on the older but not the newer?

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