gearcase drain plug leak

[panasonic]

Scott,
I don't like the drill marks on your drill press table...I hope you were not the perpetrator of that now....lol

[TownsendsFJR1300]

Scott,
I don't like the drill marks on your drill press table...I hope you were not the perpetrator of that now....lol

Heck no!!!

The Russians did it!!!




.

[Tony Sopranzi]

leaky gear case

Dealer says this morning doesn't know why its still leaking. Says the threads are fine. Wants to put in a new drain plug but has to order one in with a magnet. I'm obligated to wait for that - see if thats the problem - maybe a fracture from over torqueing?? I don't know. For now I'll have to standby.
If that doesn't work - he's at a major decision point.

I looked up the gear case exploded diagram and also the service bulletin covering the new black plug gasket installation and torqueing procedures.
Thanks to all for those suggestions as well as the helicoil and stainless
insert approach. Machinist neighbor says if they have a larger drain plug,
he would re-tap the hole for the larger size. I hope the new drain plug solves
this mess.

[pstephens46]

Dealer says this morning doesn't know why its still leaking. Says the threads are fine. Wants to put in a new drain plug but has to order one in with a magnet. I'm obligated to wait for that - see if thats the problem - maybe a fracture from over torqueing?? I don't know. For now I'll have to standby.
If that doesn't work - he's at a major decision point.

I looked up the gear case exploded diagram and also the service bulletin covering the new black plug gasket installation and torqueing procedures.
Thanks to all for those suggestions as well as the helicoil and stainless
insert approach. Machinist neighbor says if they have a larger drain plug,
he would re-tap the hole for the larger size. I hope the new drain plug solves
this mess.

Wonder if your dealer is aware of the recommendations on how to torque that new gasket/oring? Posted above in a link to a different forum.

[Tony Sopranzi]

gear case drain plug leak

Just crawled under the gear case to take some photos to show the dealer.
Appears the oil is seeping out of the center of the pilot hole thats drilled into
the top of the plug in the middle of the screwdriver slot. Another one of life's
unexplained mysteries.

[TownsendsFJR1300]

Just crawled under the gear case to take some photos to show the dealer.
Appears the oil is seeping out of the center of the pilot hole thats drilled into
the top of the plug in the middle of the screwdriver slot. Another one of life's
unexplained mysteries.

Sounds like the magnet in that lower bolt loosened up and oil's getting past it then...

[Tony Sopranzi]

leaky drain plug

Hi Scott,

Thanks for your input. Correct - I didn't look at the threads myself. The
boat is at home here in the garage and I haven't touched it for fear they'll accuse me of having boogered something. The drain plug (according to the dealer) has a new "O" ring on it. I was standing by when the tech installed
the round black gasket. I was talking with the service manager at the time and wasn't paying attention to what the tech was doing but he got my attentions when he said it feels like a burr or something up there - the plug stops turning
before it gets to its seat. But he eventually got it to seat. I wasn't aware of the new install procedure at the time having looked it up after the fact. Why is that little pilot hole on the top of the drain plug head? Is that for the lathe when the turn the threads on the plug?

[Tony Sopranzi]

gear case drain plug leak

I assumed that magnetic drain plug was all one piece. That magnet a
screw in fit or press in?

[TownsendsFJR1300]

Hi Scott,

Thanks for your input. Correct - I didn't look at the threads myself. The
boat is at home here in the garage and I haven't touched it for fear they'll accuse me of having boogered something. The drain plug (according to the dealer) has a new "O" ring on it. I was standing by when the tech installed
the round black gasket. I was talking with the service manager at the time and wasn't paying attention to what the tech was doing but he got my attentions when he said it feels like a burr or something up there - the plug stops turning
before it gets to its seat. But he eventually got it to seat. I wasn't aware of the new install procedure at the time having looked it up after the fact. Why is that little pilot hole on the top of the drain plug head? Is that for the lathe when the turn the threads on the plug?

I can't bold anything but will try to address your issues.

Frankly, I don't remember seeing a "pilot" hole in the middle of my drain plug but there is a magnet installed in that plug. Machining from the factory probably required it(I never knocked the magnet out so IDK).

It might be a communication problem, but even the new gasket (from what I can see, and how the LU was initially machined) is for a flat gasket. If their putting in a rubber style, thickish O-RING, NOT GOOD...

That "burr", when the bolt stops until forced, it's frigging CROSS THREADED, no doubt..

Yes it may be sitting flat now, but they screwed up the threads. Force anything hard enough, it'll seat.. Especially SS vs aluminum...

We both know it's a simple bolt screwed into a thread. Their NOT telling you
the threads are screwed up (as now their eating a self induced repair).

You NOT seeing the threads (and there's NOT alot there) leaves you in the dark.

As you've changed the LU oil before, un-screwing that drain bolt won't hurt anything. They've already damaged it.. And IF the threads aren't damaged, no foul, put it back, YOU KNOW, the threads are good.

Gentleman's bet it's tore up...

IMO, either pull the bolt (to inspect threads-it'll be VERY OBVIOUS if cross threaded), or have them do it and YOU INSPECT.

Them saying it didn't leak for a couple of days, but it does at your place?? C'mon, BS...


.

[TownsendsFJR1300]

I assumed that magnetic drain plug was all one piece. That magnet a
screw in fit or press in?

Very likely a press fit (snug), maybe some loctite.

Definitely was two separate parts at one point.

[rodbolt17]

if it was cross threaded it will never seal.
if you need to heli coil it you must shorten the standard coil by about 4 threads.
I do a couple every year.

[TownsendsFJR1300]

if it was cross threaded it will never seal.

It doesn't seal, it leaks..


.

[Tony Sopranzi]

leaky drain plug

Scott,
After thinking about it, I think you're diagnosis is closer to the truth.
If the magnetic tip is pressed in and became damaged somehow it would indeed open a path through the breather hole which is there so air the magnetic tip displaces when it is pressed into the stainless body has somewhere to escape. Thats why the hole is drilled through the plug.

We'll know soon enough when the new plug arrives. Thanks for taking
the time to opine.

Tony

[TownsendsFJR1300]

No problem..

Just an FYI, there is no vent hole for the LU (or water would get in). It (the drain bolt) may very well be machined, but should not allow oil out/ water in, no venting..

Hopefully that's all it is..

[dray0151]

On my plug there is as the link shows a whole in the middle of the head, I can not say what it is for but I too do not think it has anything to do with venting maybe how the bolt was cast to get the magnetic end on it. That is what the OP I think is talking about.

688-45341-10-00 YAMAHA PLUG, DRAIN