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Accidently drilled a hole in my case.

Humm, how bad is this?
I was putting on a new sump plate cover and the studs weren't long enough. So I removed the old studs and put in a 1/4" longer studs, that is about the thickness of the new plate. A couple of the studs still pulled.
So I took some measurements and went out and bought a 6mm 1.00 pitch tap and some matching bolts.
I figured I would drill, tap and mount the plates with nice long bolts 35mm, thats 1 3/8" approximately.
The original studs were 1", the new studs were 1 1/4" approximately. Everything looked perfect until I started to drill my first hole.
Bam, too far, right into the case, oil comes pouring out. So I throw the drip pan down, tap the hole and screw in the new longer bolt. It is good and tight. The oil pouring out of the hole really helped with the tapping. Great.
I was planning on doing all this with the sump cover on and just one bolt at a time. I was going to just pull one stud at a time, drill, tap and replace all 8. I wanted to do them all, but I am a little worried now. I wasn't planning on drilling into the case.

How bad did I screw this up? Or will I be OK?

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Old 08-31-2014, 03:50 PM
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which one was it? they seem pretty fortified from this pic I found from when I did my motor. looks as if the one that would scare me most would be the ones closest to the case seam




on the bright side the cascading oil pushed all the drill shavings the right way, out of the motor...
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Old 08-31-2014, 04:00 PM
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Thats the passenger side of the motor right? It is the one on the left of the 2 showing. I couldn't believe it, I had the drill bit marked and I was only going to go 1/4".
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Old 08-31-2014, 04:33 PM
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DIPSO... Really?

Please don't drill any more stud holes. You can use some of these to "fix" the thread for each of the studs remaining.
The one you've already done should be OK assuming it doesn't leak, just makes sure there are no alloy chips sitting next to the hole inside the engine.

You can get Size M6. The smallest I've got is M5 which I used to fix the threads in my tail light housings.

Good luck.

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Old 08-31-2014, 04:49 PM
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this one?



i might expect that one to be the least worrisome. yes, passenger side of the case.


you might consider chasing the threads, get all the oil cleaned and lock-tite the f out of it.
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Old 08-31-2014, 05:51 PM
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My mistake. It would be the one, two to the right of that, at the other nub.
I just drained the oil from the case, started it up and let it run for a few minutes. Doesn't seem to leak and all the other studs are snug. I think I am going to leave it and see if it leaks.

Stuck my finger up inside and around the drain hole and everything feels clean. Any big pieces are outside the screen. Worst case scenario, a piece broke off inside as the drill bit pushed through. Could a 6mm size piece of magnesium cause much damage in the lower case?
Or would it be ground up fairly easily?
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Old 08-31-2014, 06:12 PM
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I think I am going to pull the sump plate, look for metal outside the screen. remove the 1 3/8" bolt and thread a 6mm" plug up there with loctite.
Then buy shorter bolts, probably 3/4" or 1" and one of those recoil kits and put them in all 8 holes. Then reassemble with the shorter bolts.
I would imagine that is as good as it can get.
Any other suggestions?

Is Recoil better than Heliocoil as far as thread saver systems go? I have never used either.
What about taping my existing 6mm holes into 8mm holes and just using a 8mm/6mm stud?

Damn, this was all to stop a stupid leak and I had it stopped except for that one bad stud. Now I have a whole can of worms to deal with.
I do like the new sump plate cover though. Man, what a job.
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Old 08-31-2014, 08:39 PM
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don't metric bolts come in metric lengths?

Like 1" is 25mm etc..

The right wasy to do is is helicoil or recoil.

DON'T drill it bigger.
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Old 08-31-2014, 10:02 PM
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Well, no chunks of metal in case, a few shavings outside the screen but I cleaned them out, drilled nub is in good shape, not broken.
8 new heliocoils, 8 tempered studs that came with the thicker sump, didn't have to screw them in so far with the heliocoils to get them to bite. 6mm plug screwed and loctited into top of drilled nub.
Plate snugged down real tight, all the way around.
Almost a catastrophe, but I think I saved it.
What a day.
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Old 09-01-2014, 01:43 PM
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Glad to hear it went well in the end!

This is why projects that should take 1/2 hour end up taking days.
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Old 09-01-2014, 03:08 PM
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I haven't put oil in yet and was wondering if anyone has any concerns?
My only concern is that the plug may work itself it out, and cause some damage somewhere by getting jammed. The plug is 1" long and 6mm in diameter.
If the plug did come unscrewed, against gravity, wouldn't it just fall to the bottom.
It looks like with the height of the timing chain pulley, there is no way the little plug could ever get high enough to lodge itself.
My other concern is that it could get between the screen and pick up tube and end up wherever that leads.

It can't get into the piston chamber, right?

What's the level of oil in the bottom of the case? I think gravity might be on my side.
Old 09-06-2014, 04:57 PM
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Quote:
Originally Posted by dipso View Post
I haven't put oil in yet and was wondering if anyone has any concerns?
My only concern is that the plug may work itself it out, and cause some damage somewhere by getting jammed. The plug is 1" long and 6mm in diameter.
If the plug did come unscrewed, against gravity, wouldn't it just fall to the bottom.
It looks like with the height of the timing chain pulley, there is no way the little plug could ever get high enough to lodge itself.
My other concern is that it could get between the screen and pick up tube and end up wherever that leads.

It can't get into the piston chamber, right?

What's the level of oil in the bottom of the case? I think gravity might be on my side.
A threadedplug installed with a sealant shouldn't dislodge. May be possible if someone tries to install a regular length bolt into that hole, but not likely. However, some inserts aren't solid, just wound wire. The sump cover threads might lie outside the crankcase screen, so would be separated from the pump by the screen (please confirm).

Another option is use a closed-end thread insert. No plug required. Just seal the external body to prevent a leak path. Some require special installation tools (e.g. Riv-nuts). Others may have external threads to provide more area for sealing.



https://images.search.yahoo.com/search/images;_ylt=AwrSbgK0qgtU1WIAQZNXNyoA?p=closed+end+ thread+insert%2C+metric&fr=ytff1-yff30&fr2=piv-web

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Old 09-06-2014, 05:46 PM
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Yes, the sump cover threads and the blocks they are threaded into, are outside the screen.
And I think the threaded plug was 1/2 " not 1".

Old 09-07-2014, 05:54 AM
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