Valve cover center nut?

[Boxerkuh]

Greetings, I have a technical question:

I wanted to adjust my valves today, but a problem came up early and I need some advise. I unscrewed the center nut from my left valve cover and the whole stud came out; nut, washer and stud. :scratch I know that that is not normal, so since it is a daily rider, I put it back in and checked the other side. It was okay.

So the question: How do I proceed and fix this? Just adjust the valves and use some red lock-tight to put it back in and hope that next time the stud stays in? Or adjust the valves and before putting the valve cover back on, use red lock-tight and put the stud in, then tomorrow morning try to get the nut off and put the valve cover back on? I can't imagine that I am the first person that this has happened to, but what is the solution? Do I use red lock tight or something else? All the threats look okay, I must have put too much torque on it last time... Please advise...:scratch :dunno

Thanks for your help, in advance..:ear

[20774]

No, you're not the first! I had one pull out on my new-to-me R69S...

I'd go ahead and complete the valve inspection while you consider your options. There's probably not too much to worry about as the center nut is probably not doing that much, provided your valve cover and head are co-planar, ie, flat. The outer two nuts-studs are doing a good job of holding everthing together.

A number of fixes include:

- if you're lucky and there still some threads, you can clean everything up and use red loctite to reset the stud. Look at the other side to get a sense how far out the stud should be.

- try to install a helicoil or timesert with the head installed. This can be a bit tricky if you don't get the stud aligned square with the head. Also, be wary of the swarf that will end up in and around the head. This might be best done with the head off, if you were planning on doing that.

- find some metric all thread and cut off enough so that the thread will stick through into the small opening just under the spark plug. You should be able to look down from the top and see this opening. With the proper metric nut, with the edges ground down somewhat, you can drop it down in the opening and engage the threads from the stud. Use red loctite. The length has to be near correct to ensure you've got enough threads to engage with the acorn nut and not too much that the acorn nut bottoms out on the inside. A few washers could help that if you get too long.

The center nut doesn't need that much torque once you get everything back together.

[dlearl476]

From your post, I'm not sure your threads are damaged, as Kurt assumes. If they aren't it's no big deal. Just double nut the bottom of the stud and remove the cap nut. Clean the threads off, then re-install the stud. I'd use blue loctite, not red. Unless you damaged the threads in the head, the stud coming off with the not isn't really any big deal.

I must have put too much torque on it last time... Please advise...

I think it happens from corrosion getting into the cap nut threads. This is really common on oil sump studs/nuts. Last time I did my 911 oil, half the studs came off with the nuts.
To combat this, I like to use Boesheild T-9 or LPS3 Anti-Corrosion spray on the threads when I assemble them. Helps keep them clean and easy to remove.

[Boxerkuh]

Thank you so very much for your feedback. I also spoke with my Airhead Guru and he told me that all I needed to do is my normal valve check. Then he stated for me to get the exisiting nut off the bolt and to re-install the stud with blue loctite and finger tight would be okay. He stated that the center stud nut requires very little torgue (8lbs is enough) and the valve cover should not leak if the nut/stud is not there. He further advised me if that did not work, the next time, we could helicoil the stud hole prior to installing the valve cover. A quick and simple fix. :dance

[widebmw]

- find some metric all thread and cut off enough so that the thread will stick through into the small opening just under the spark plug. You should be able to look down from the top and see this opening. With the proper metric nut, with the edges ground down somewhat, you can drop it down in the opening and engage the threads from the stud. Use red loctite. The length has to be near correct to ensure you've got enough threads to engage with the acorn nut and not too much that the acorn nut bottoms out on the inside. A few washers could help that if you get too long.

The center nut doesn't need that much torque once you get everything back together.

A 75mm stud will work.

[Isamemon]

I guess Im not that good
to say that a helicoil is a quick and easy fix
never seems to go that easy for me
then again I have big clumby hands

[bearsfolks]

When the left side came out I had a local m/c shop install a helicoil. When the right side came out i got a threaded rod, cut it 1/4 inch longer that the original, then coated the threads with JB Weld and screwed it back in. Now when I need to remove the cover only the acorn nut comes off.