Author Topic: Stripped threads in engine for oil plug! What do I do now? (Read 10169 times)

Laurence · **on:** November 21, 2009, 02:51:21 am

Last time I changed the oil in my AVL I over tightened the engine drain plugs. Tonight I just changed the oil again, and when I couldn't get the back plug to screw in, stuck a pencil covered with a cloth up in threaded hole and withdrew this:

about three turns of thread in my hand.
Now when I begin to tighten the plug, after it gets hand tight and I begin to tighten with a wrench, a quarter turn more and its loose again.

What do I do now?

Kevin Mahoney · **Reply #1 on:** November 21, 2009, 03:07:45 am

STEP AWAY FROM THE MOTORCYCLE!!

This is easier than you think. Take the plug down to your NAPA store or other auto parts place. you will find some plugs made of rubber that will expand when you tighten the plug. Or you will find some self-threading plugs that are just a bit bigger than the stock plug. You can also buy a heli coil and put in a steel thread.

It's not as bad as it sounds.

Laurence · **Reply #2 on:** November 21, 2009, 03:37:21 am

Quote from: Kevin Mahoney on November 21, 2009, 03:07:45 am

STEP AWAY FROM THE MOTORCYCLE!!

This is easier than you think.

Well - stepping away from the motorcycle went pretty well.

Though the lingering tastes of stupidity don't do down too good.

Quote from: Kevin Mahoney on November 21, 2009, 03:07:45 am

This is easier than you think. Take the plug down to your NAPA store or other auto parts place. you will find some plugs made of rubber that will expand when you tighten the plug. Or you will find some self-threading plugs that are just a bit bigger than the stock plug. You can also buy a heli coil and put in a steel thread.
It's not as bad as it sounds.

No, it doesn't now! thanks.

I like the idea of the expanding plug as a first temporary fix. I just watched a video on U-tube showing installing the helicoil - looks tricky to keep from getting metal pieces up in the crank case - (that little cross piece in the end of the Helicoil insert has to be knocked out before you screw the bolt in - and how would you be sure you got all the pieces out?),

chumma7 · **Reply #3 on:** November 21, 2009, 03:44:47 am

Quote from: Laurence on November 21, 2009, 03:37:21 am

Well - stepping away from the motorcycle went pretty well.

Though the lingering tastes of stupidity don't do down too good.

No, it doesn't now! thanks.

I like the idea of the expanding plug as a first temporary fix. I just watched a video on U-tube showing installing the helicoil - looks tricky to keep from getting metal pieces up in the crank case - (that little cross piece in the end of the Helicoil insert has to be knocked out before you screw the bolt in - and how would you be sure you got all the pieces out?),

Go to napa and ask for part # 704-1019. It is a self taping drain plug that fits perfectly. Take your old plug to napa to check for size just in case the avl drainplugs are different than the old engines.
you can order it online here:
http://www.napaonline.com/NOLPPSE/(S(ktc5qy45a11j1q55kl1kz045))/Detail.aspx?R=BK_7041019_0071192868

When you get the plug you will notice it has a little 8mm plug inside of it (piggyback plug). The bigger, outer section is what cuts new threads into your case. Drain all your oil and then slowly twist the self tapping plug in (twist it in half a turn, then out a quarter...then in a half turn, out a quarter, etc.. make sure you are removing the shavings as you do this). You can also add a dab of vaseline at the tip of the drainplug for the shavings to stick onto. Once you have it tapped all way in, remove it and pour a solvent such as naphtha into the oil tank from the top. This is to make sure you have gotten rid of all the rest of the aluminum shavings. Trust me.. the shavings will come out with the solvent if you use enough of it. I had this problem 18k miles ago.
After you are sure there are no shavings left inside the oil tank, use some red thread lock on the new drain plug and screw it in for good. The 8mm piggyback screw is what you will use for future oil changes.
-chumma

ScooterBob · **Reply #4 on:** November 22, 2009, 03:23:00 pm

Quote from: Kevin Mahoney on November 21, 2009, 03:07:45 am

STEP AWAY FROM THE MOTORCYCLE!!

Now THERE is some good starting advice if EVER I've seen any .... Hahahaha!! Way to go, Jefe!

UncleErnie · **Reply #5 on:** November 22, 2009, 04:45:30 pm

I recommend against pressure or compression plugs. My experience is that they can be hell to get out again. For something that you'll need to take out on a regular basis (oil changes)- forget it. It's something an unscrupulous seller would employ for a quick sale- not a proper fix.

I have used both other medoths mentioned. If you use a heli-coil, check to be sure you can get the proper size drain bolt FIRST.

In either case, use lots of grease for shavings to stick to, and remove/clean the tap often. Final rinse as prescribed (but it's probably not even necessary)
Also, it will be easier to access the hole if the lean the bike way over and rest it on something. You may want to drain the gas first...

Vince · **Reply #6 on:** November 22, 2009, 04:59:37 pm

I always repair this with a thread insert such a Time-Sert tm. This is a solid (as opposed to the helicoil) insert that is threaded inside and out. New threads for the insert are cut into the case. The outer lip of the case is countersunk to accommodate the lip of the insert. The insert is then threaded in with a special tool that spreads the inside end to lock it in place. When properly done it is a permanent repair that is stronger than the original.
A helicoil is cheaper, quicker, and easier, but has a high failure rate for constant use threads such as drain plugs and spark plugs. The time-sert kit is expensive and should be done by an experienced machinist/mechanic, but it is a permanent repair. When the helicoil fails the repair usually involves engine dis-assembly. I use helicoils on blind holes that won't allow use of the tooling for the time-sert.
Use a 14mm, 1.25 thread insert. This is a common size on many motorcycles including your AVL. Thus you will be able to use common standard parts after the repair.

Ice · **Reply #7 on:** November 23, 2009, 07:56:27 am

Vince, were the people using the heli-coils also using the the required special heli-coil tap ?
I ask because heli-coils have given me good service in fleet applications for quite some time.

t120rbullet · **Reply #8 on:** November 23, 2009, 02:34:14 pm

Quote from: ScooterBob on November 23, 2009, 02:28:44 pm

Wow! Can I get a drain plug for my New York Asian Escort ..... in New York - with an Asian Escort? ..... Somebody is about to get nuked ......

Your a bad, bad boy!
You probably need to be spanked.
CJ

Vince · **Reply #9 on:** November 23, 2009, 05:56:14 pm

Quote from: Ice on November 23, 2009, 07:56:27 am

Vince, were the people using the heli-coils also using the the required special heli-coil tap ?
I ask because heli-coils have given me good service in fleet applications for quite some time.

Ice, it is not a matter of installation technique.There is nothing to lock the Helicoil in place. A little piece of dirt or corrosion can cause it to spin out with the bolt. Locktite doesn't work because inevitably some will squeeze out between the threads and the bolt will adhere or grab it. The Time-sert is a tapered solid insert. I find them to be more reliable.

birdmove · **Reply #10 on:** November 23, 2009, 07:28:06 pm

Also, I think the Heli-Coils have to come in a kit, and they use a special size of drill very often. I think the ones Vince is suggesting, yoo can use a common size drill bit and tap. I have only used the Heli-Coils when I worked as a truck mechanic. We had some of the other type-I just never used them.

jon

Geirskogul · **Reply #11 on:** November 24, 2009, 04:08:09 am

Heli-coils are really best in sunk, bottomed inserts or in THICK pieces of metal. The thin drain wouldn't be the best for one. What vice is suggesting or the NAPA part are better ideas - I concur!

Kevin Mahoney · **Reply #12 on:** November 24, 2009, 04:37:21 am

i second the motion

Ice · **Reply #13 on:** November 24, 2009, 06:45:27 am

Is it posible that we are talking about two different brand of insert coils ?

The genuine heli coill brand inserts I am familiar with require the use of a special non standard heli coil tap to cut special threads whose under sized I.D. is smaller than the inserts O.D.. The coil is is considerably reduced in diameter as it is screwed in. Outward spring tension of the coil locks it in place.
We never needed to lock tite the heli coil in fleet service or in high H.P. air cooled V.W. sand rail engines. I agree the Time-sert, keen sert and NAPA plug would indeed be nicer for a drain plug application.

Vince · **Reply #14 on:** November 24, 2009, 06:20:20 pm

Yes, Ice, we are communicating as to exactly what product is under discussion. i base my preference on my experience in the last 35 years in the industry. The helicoil has its uses. i actually us it more often than the Time-sert. But certain applications such as drain plugs and spark plugs are better addressed with the solid insert

Laurence · **Reply #15 on:** January 16, 2010, 09:18:48 pm

Well my Bullet is fixed! Rich at R&D researched several options and chose the Time Sert. No ugly plug showing. He did a beautiful job and there is no evidence of the repair - looks exactly as it came from the factory. Nothing like having a dealer who knows exactly what he's doing, and does it so well. Lucky me!

Rick O'Shea · **Reply #16 on:** January 16, 2010, 09:37:33 pm

Yea, Rich Is one squared up fella. I'm kinda fond of the cute barefoot carburetor specialist too.

Laurence · **Reply #17 on:** January 17, 2010, 12:07:11 am

Quote from: Rick O'Shea on January 16, 2010, 09:37:33 pm

I'm kinda fond of the cute barefoot carburetor specialist too.

yeah me too - you don't find that at just any Enfield dealer (Vince will be envious)

KB8ANY · **Reply #18 on:** January 26, 2010, 03:16:59 pm

Yo:

I'm glad Laurence got his plug fixed - nothing builds confidence like having confidence in your gear.

I'm going to use Kevin's expansion-plug fix if it ever happens to me. The only thing I might change is to buy more than one and maybe replace it every time I change the oil. I'm sure that the routine filling-station walk-around / inspection (that, of course, we all do without fail at every fillup) would reveal any impending oil leak at the plug 'way before it could become catastrophic.

Paul

jayprashanth · **Reply #19 on:** January 26, 2010, 05:26:53 pm

Now gentlemen, how do we avoid over tightening the drain plug? I'm a novice and I'm going to change my AVL500s engine oil shortly. Never done it before but I now find that wrenching around is therapeutic for me. So, I'm all set to do stuff myself. How do I make sure that I don't overtighten the drain plug? Any specific technique to employ or tips from your experiences would be terrific for a newbie like me?

Cheers,

Jay

cyrusb · **Reply #20 on:** January 26, 2010, 09:50:02 pm

I have used my drain plugs 5 times since new. Once a season, on the other changes that occur during the riding season i suck it out with a pump. The Enfield engine is really easy to do this, and on the side stand all the oil can be pumped out. Why ask for trouble?

Laurence · **Reply #21 on:** January 27, 2010, 03:44:29 am

jayprashanth - the key to not over tightening the drain plugs is simply that little copper washer/gasket under each one of them.They get hard and inflexible over time. Each time I've changed the oil filter I've wondered what those three shiny new copper gaskets were for - certainly not for the filter. So I kept using the copper gaskets that were already on the bolts. These got crushed and inflexible over the last 8,000 miles, but I kept wrenching them down to keep the oil from leaking and so finally stripped all the threads out. But aha! now I know they are in the oil filter kit to replace the three copper gaskets on the three drain plugs. So it's simple really: every time you change the oil filter, put the new copper gaskets on the drain plugs. Good luck.

jayprashanth · **Reply #22 on:** January 28, 2010, 12:52:44 pm

Thanks Laurence, I'l stock up on the copper washers then. I appreciate all the suggestion guys. Thanks all.

Cheers,

Jay