Magnetic Drain Plug DANGER!

[China Rider 27]

Working on the oil cooler today finishing it up and went to tighten up the drain plug to put some oil in it. I always use a torque wrench to 18 ft lbs. If anybody has every tightened a bolt and then felt that easy kinda turn when it should be getting tight which leads to that sickening feeling in the bottom of your stomach you know it is stripped but, in this case, the bolt head twisted completely off the aluminum magnetic drain plug! #%%@#^&&% That’s trouble. Visions of case splitting in my head. I tried to drill the magnet, seemed as hard as a diamond no go. Seemed the only choice was to drill completely around the magnet with a small bit and punch it threw and clean it out. As I went to drill it on the edge it moved! Hallelujah, its loose, and I used the sharp corner of the drill bit to work it around and out. Worked fine for 4 oil changes, paid $9.00 for it. Very poor aluminum alloy and weak around the magnet. Sometimes does not pay to go inexpensive as much as we all appreciate the savings. Needs to be steel. If you’ve got one in your engine, I highly recommend get rid of it QUICK!

https://ibb.co/XVVMH9M

[Spins]

Thanks, I’ve been looking at these on Ebay.

[ChillRider]

FWIW I read somewhere that the torque figures for drain bolts on these Yamaha and Honda chinaclone engines (usually taken from the original manuals) are actually considered quite high and damaging even for the original engines (e.g. the TW200's 20-30 Nm spec, which in my experience is actually way a bit too much on the tight side). Maybe it pays to ease a bit back on the torque, esp. with aftermarket plugs.

[China Rider 27]

I agree, might be a good idea to take a few lbs off say 15 ft lbs or 20 nm. I may try 10 and see how it goes but the other side is these motors have a lot of vibration. The standard steel plug torqued right up firm to 18 ft lbs with no feeling of give or looseness or stripped threads. The real issue I had is poor quality aluminum in the plug with weak overall mass around the magnet providing reduced resistance to torque. No matter the force, it was bound to fail one day just a matter of time. No more aluminum for me strictly steel.

[Megadan]

I tighten to maybe 15ft-lb tops on my normal steel drain plug. New crush washer and I also put a bit of hylomar on the threads (non-curing RTV) to prevent thread leaking as well as acting a bit like loctite to the drain bolt. It cleans off easy with brake parts cleaner and a brush when doing an oil change.

I wouldn't use an aluminum bolt though in any case. Stick to steel. Aluminum means that the magnet is glued in place, and that also means it could come loose.

[China Rider 27]

I have never been a "new crush washer" kinda oil change guy over the years putting the old washer back in. I ordered some rubber center crush washers and will give it a try. Stands to reason it will function some like a lock washer when crushed. Holy smokes that Hylomar is expensive from what I see on amazon. One can always revise their practices to if not best, better.

[tknj99]

I dont bother with a torque wrench on the oil drain bolt and go by feel, staying on the conservative side, ie i don't over tighten it. As long as the washer is good you shouldnt need to tighten much. One thing that i used to suck at that i've gotten better at with time is learning not to over-tighten bolts, i used to go that extra ugga-dugga and then kick my self later when i was dealing with a stripped nut which ruins the day for sure.
For most things though i do like to use the torque wrench when there is an accurate and specified value for the application.
Funny story about my first torque wrench experiences.. i bought an torque wrench that has a 10 ft/lb- 80 ft/lb spec... and made 2 boo boos.. first was when i used it to tighten the hydraulic fluid drain bolt for the rear axle on a Honda Fury which called for 8 ft/lb's if i recall.. i set it to 8 ft/lb and kept tightening but never heard a click and was like hmm.. ok.. and kept going until i realized something was wrong.. luckily i didnt strip it too bad and later realized that the spec range means you only use it for 10 ft/lb's and up, not for anything under 10 ft/lbs
second oh f moment was when i went to do a valve adjustment on the same bike and researched the torque spec for the locking nut. cant recall what it was now but say it was 20 ft/lbs.. for some reason i got the bright idea to verify that it was in fact at the 20 ft/lb's already from stock and set the wrench to 20 ft/lbs and cranked it... turn, turn, no clicking and then it starts spinning faster.. ugh oh!! i stripped the lock nut, couldnt do the valve adjustment and in the end had to get the bike towed to Honda dealer to replace the valve adjustment screw and locknut and then i had them finish the job..
sometimes we have to learn the hard way

[China Rider 27]

Originally Posted by Megadan

I tighten to maybe 15ft-lb tops on my normal steel drain plug. New crush washer and I also put a bit of hylomar on the threads (non-curing RTV) to prevent thread leaking as well as acting a bit like loctite to the drain bolt. It cleans off easy with brake parts cleaner and a brush when doing an oil change.

I wouldn't use an aluminum bolt though in any case. Stick to steel. Aluminum means that the magnet is glued in place, and that also means it could come loose.

Got me some of that hylomar $9 amazon. I put some on the drain plug around the base yesterday when I changed oil and as a little test I torqued it to 10 ft lbs. Today I had to drain the oil again because of a leak and I was surprised at how well it acted as a thread locker. Initial torque broke with little firmness but the drain plug held well and had tension for a good many turns. Put oil back in and some hylomar on the plug torqued to 10 ft lbs and went for 20 mile ride. Still seems tight according to finger pressure.

[Megadan]

Originally Posted by China Rider 27

Got me some of that hylomar $9 amazon. I put some on the drain plug around the base yesterday when I changed oil and as a little test I torqued it to 10 ft lbs. Today I had to drain the oil again because of a leak and I was surprised at how well it acted as a thread locker. Initial torque broke with little firmness but the drain plug held well and had tension for a good many turns. Put oil back in and some hylomar on the plug torqued to 10 ft lbs and went for 20 mile ride. Still seems tight according to finger pressure.

The hylomar thing is just something I have always practiced with any hydraulicnor or oil fitting. It's a good little extra insurance against leaks at the very least. Plus, a little goes a long way. That tube will last for years lol.

As far as the crush washer thing. I will reuse them once or twice. As long as they aren't mushed into the threads of the bolt. Annealing them with a torch can also get a bit more life out of them.

[China Rider 27]

Yaa I'm down with the Hylomar now! LOL Amazing, I didn't clean the threads and it just kinda pushed the oil out of the way and grabbed ahold? It will come in useful for something else. I saw on line where they old school used it to make gaskets on two surfaces and put a piece of thread in it to seal!

[TheChairman]

Anyone have a link for a steel magnetic plug that fits?

I ordered an aluminum one, but haven't installed it yet. For $9 or whatever I paid for it, it's not worth having to take the time to fish it out if it does break.

[Megadan]

Originally Posted by China Rider 27

Yaa I'm down with the Hylomar now! LOL Amazing, I didn't clean the threads and it just kinda pushed the oil out of the way and grabbed ahold? It will come in useful for something else. I saw on line where they old school used it to make gaskets on two surfaces and put a piece of thread in it to seal!

I don't clean the threads for the oil being on them, I clean off the old hylomar just to make way for the fresh stuff. It tends to stick to the clean bolt better than the oil soaked case threads as well, making sure it mostly comes out with the bolt.

Also, yes, it makes a great gasket maker for parts that may need the ability to move without cracking due to differences in expansion rates, like an aluminum valve cover on an iron head. It also works great for sealing gasket-less side cases on some modern motorcycle engines, like my VFR. Since it is semi-curing it always retains a bit of flexibility and the slightest bit of tack.

[China Rider 27]

I did the same, cleaned the drain plug with brake cleaner and a crush washer, apply little around the base and if you wipe off the flat surface of the case with paper towel and brake cleaner it sticks to that. The case threads have oil on them. Probably stick with no torque! LOL

I noticed my original drain plug had some white stuff on it that must have been hylomar. Probably don't want any chance of leakage during shipment but that says something about the engine manufacturer. Then it made me think, you know if you have a bullet proof engine, you can build something that will sell at the right price, and people will put up with a lot of other less desirable accessories and will fix it, but it won't go without a good engine reputation.

[EA]

Stick with high quality parts for sure. I can not tell you how many oil pans I've replaced from people using cheap plugs and or over tightening them.
I don't torque the drain bolts either. Snug and a gentle tap works like a charm and I've never overtightened or stripped a pan.

[Biker_Andy]

New oil drain plug at CSC is $0.32 and crush washers are $0.12... just saying