Lower Unit drain plugs holes not smooth

[panasonic]

Agree. It's likely not the "normal" thing they do. Some machine shops have some very creative and talented people working there, though. At a minimum, it would likely be worth a conversation. A long piece of all thread screwed into the drive can be used get it set perpendicular to the drill press with a rotating table. Ratchet straps, clamps and shims can help hold it in place. I know that sounds a little MacGyver-ish... and there's probably a better way - that's just the first idea that popped in my head.

You are correct Dennis...set up is everything in machining. I have literally spend days setting up a part in the milling machine just to do a an hour of actual machining. And that's were the cost of bringing something to a machine shop gets very expensive fast...setup and having the right tooling.

Your quote:

"On the other hand, if you can clean it up really well... REALLY well... then I think your idea of epoxy (like Marine Tex or PC-11, etc) and a stainless washer will most likely be just fine. You won't need (or want to use) much goop - and even though it will likely be cured in a day, I would give it at least a couple days for good measure. Use your drain screw to hold the washer gently, but snugly, in place while it dries. Apply some wax to the screw threads - just in case a little goop squeezes out on the threads, it won't stick."

Very good plan if going to try the washer repair.

I still think that getting it cleaned up and as flat as possible first would be needed so that the washer will end up being stuck where it needs to be.

What to bond it on with is another thing...things dont like to stick to stainless well. I definitely would not use JB Weld as it gets brittle.

[panasonic]

This site keeps kicking me out before I can finish typing my response...FFS

[DennisG01]

What to bond it on with is another thing...things dont like to stick to stainless well. I definitely would not use JB Weld as it gets brittle.

Agree. I would severely roughen up the mating side to give some mechanical tooth to the bond.

[rubilacx]

I am planning to give the stainless washers a go first. Definitely going to get it super degreased and scuff the stainless a good bit. After consideration, I can always go back to the boring technique if it doesn't work out. I will post some pics and results soon...!

[DennisG01]

I am planning to give the stainless washers a go first. Definitely going to get it super degreased and scuff the stainless a good bit. After consideration, I can always go back to the boring technique if it doesn't work out. I will post some pics and results soon...!

Sounds like a good plan. Don't overdo it with the goop!

Good luck!

[DennisG01]

Side note... using a counterbore cutter bit... since you're dealing with aluminum and only need to shave off a tiny amount... Panasonic, what do you think of just doing that by hand?

[boscoe99]

A washer and epoxy is a half assed measure IMO. Especially when a spot facer is so cheap and effective.

[panasonic]

Side note... using a counterbore cutter bit... since you're dealing with aluminum and only need to shave off a tiny amount... Panasonic, what do you think of just doing that by hand?

Putting the counterbore in a drill on slow speed and just barely turning it is what I mean by doing it by hand.

Sometimes we just put the cutter in a air drill and turn the chuck by hand to clean up existing spotfaces...no air line attached. It works well... especially on aluminum.

[panasonic]

A washer and epoxy is a half assed measure IMO. Especially when a spot facer is so cheap and effective.

Yes counterbores are cheap now...all made overseas. Finding the right size is a little bit of work sometimes.

[rubilacx]

Well.... here is the end result. I took two 316 stainless M8 washers and ground them down to the exact OD of the hole. Cleaned up all of the areas with engine degreaser and washed it down good, dried, etc. Used JB Marine Weld, which was a good paste consistency and filled in the outer ring and gaps. Coated my plugs with antisieze to keep the weld from sticking to the plugs. I put the plug in the washer and snugged it up good into the JBWeld. I noticed a slight amount came out and around the outsides, which was good. Every 2 hours or so I came out and unscrewed the plugs and put it back in just to be sure they didn't get welded in.

I'm going to wait 24 more hours and then do a pressure/vacuum check on the lower unit but I can already tell this is going to be a success. I don't think anyone would be able to tell this isnt better than original!

Pics attached

[DennisG01]

I'm not following... why (2) washers? And where is the SS washer? The thought process was to leave it there.

[99yam40]

I'm not following... why (2) washers? And where is the SS washer? The thought process was to leave it there.

I am sure it was 2 because of the drain and top vent screws.
The SS washer is there, but there is anticize on it in the pic

[rubilacx]

I'm not following... why (2) washers? And where is the SS washer? The thought process was to leave it there.

Sorry for the confusion, 99yam40 is right it's just one washer per hole... but both the drain hole and the vent hole had the issues so I had to do both. The fact you can't see the washer in the hole is a testament to how well it fits... !

Also, yes there is some antiseize on the top of the washer I didnt clean it for the pic.

[DennisG01]

Ah, gotcha. I thought the plan had changed and I missed it

[rubilacx]

I'm extremely happy with the results on both. I distinctly had the thought... ok worst case we get a new lower unit just go for it. It's usually these little odd situations that wind up being a major deal so I'm glad this one turned out ok (so far). But I can't imagine it going wrong since the plug itself will be holding in any jbweld issues. Aka no forces trying to separate it.