>> Hello Paul-
>>
>> So the cause of my leaking oil has been found. I have determined
> that
>> quite a few of the tapped oil pan bolt holes in AL parts have been
>> stripped. I have not surveyed all the bolts - I'll be pulling the
>> engine off again to do that on Tuesday. But I did find 4 already
> that
>> are stripped. I pulled the bolts out & they are fine. But when
>> inserted, they cannot be torqued to the spec - they spin & spin...
>>
>> So I suppose I could thin some JB Weld and re-tap the holes, but
> given
>> my tapping skills, that sounds like a recipe for disaster. I was
>> thinking instead of cutting the heads off of some appropriately
>> sized AN
>> bolts, flooding the bolt holes with JBWeld, and then inserting the
>> bolts
>> head-side first. Since the pan only calls for ~ 8fp of torqued, I
>> figure this is a simple and reliable way to get studs for the
> stripped
>> holes that I can then put metal stop-nuts on to secure the pan.
>>
>> Comments?
>>
>> Mark (Rocky Mtn High)
>>
>> You must of read my mind. I was just thinking about your engine.
>>
>> No no don't do that. Get some helicoils and a special tap.
>> I am sure you can do it if you use the proper drill.
>> Use google to check for the drill sizes.
>> McMaster also gives the drill sizes on the web site.
>>
>>
http://www.emhart.com/products/helicoil.asp
>>
http://www.roadstarmagazine.com/modules.php?
>> name=News&file=article&sid=233
>>
>> In Mcmaster Carr speak they are called "Helical Inserts".
>> Available in both metric and English sizes. Come in a kit with the
>> drill
>> and special tap. I think those pan bolts are 6 mm.
>>
>> Also "Thread Inserts" that require a some what larger installation
>> holes.
>>
>> Other than the oil leak how is the p-port engine running.
>>
>> Paul Lamar ...No rotor no motor.
>
> I have also found several stripped threads in the same location. If
> the holes are already stripped, then helicoils are the answer.
> Small threads in aluminum are easy to strip. I think it would be a
> good idea to run a clean out tap whenever reinserting these bolts and
> use a torque wrench. Jerry
>
>
> I was doing research on this on some machinists sites & came
across the
> suggestion to braze the stripped hole using a certina
product. Here's a
> snippet from their website:
>
>
>
> Thread Repair - Helicoil Thread Repair Alternative
>
> Thread repair is easy with the HTS-2000 second-generation
> brazing rod. If you're looking for a Helicoil thread repair
> alternative you've come to the right place. With our
> industrial-strength brazing rod, simply fill a hole with the
> brazing rod material and drop a hot steel bolt into it. When
> cool, the steel bolt can be backed out and new threads are
> produced.
>
> You probably know that sickening feeling already. You've
> tightened a bolt almost as tight as it can go and you give
> it that one last twist "just for good measure" and then you
> feel the wrench spinning freely and loosely. You've stripped
> the threads. With our HTS-2000 brazing rod, you can complete
> your thread repair in minutes.
>
> The HTS-2000 is permanent, erosion resistant and can be done
> with any torch. Three times stronger and more flexible than
> the first generation rods, the thread repair made with our
> product is stronger than the original material.
>
> Simpler to use than Helicoil, our HTS-2000 brazing rod can
> repair threads for many automotive, aerospace, military and
> industrial applications. Unlike Helicoil, there are no
> inserts, taps, gages and tang break-off tools to mess with.
> As with Helicoil, though, you will most likely need an
> oversized drill bit to drill out the hole, first.
>
> Instead of placing inserts into the hole, use a torch and
> drop some off our high-tech brazing rod material right into
> the hole. Heat the steel bolt to 750-degrees or above and
> drop the bolt into the hole. Let the metal cool for 15 - 30
> minutes and then using a wrench, back out the steel bolt
> from the hole. Your thread repair is complete. You've just
> repaired a thread faster, more efficiently and stronger than
> a Helicoil thread repair.
>
> The HTS-2000 second-generation brazing rod requires no flux,
> is stronger than the base metal and melts at 500-degrees
> below that of aluminum. No welding machine is needed as any
> torch such as propane, butane, mapp, or an oxy-acetylene
> will do. For expert thread repair, you don't have to be
> expert to use our high-end brazing rod.
>
> See the video for more details.
>
>
> The video is quite impressive. Anyone have thoughts on this
before I go
> out tomorrow & buy some inserts?
>
> Mark Rocky Mtn High
>
>
Hi Mark,
Sounds like you have had more than your share of challenges with that
engine. To save you some future frustration of finding oil leaks and
pulling
your engine once again I would advise to forget the brazing rod
idea. It is
a bandaid solution and one I would only use if I was stranded in
some remote
place and needed to get home. Consider replacing all questionable
threads
with an insert like Bill or Rob suggested. Just my two cents..
Regards
Doug Fir
Well, based on everyone's input (and since I can get Helicoils locally)
that is the direction I will take. Thanks for the advice -- now if only
I can get past all the engine-building issues and get onto the
engine-tuning issues...
Mark Rocky Mtn High
I'll second that Mark. We both have a lot invested in this engine and many people are
waiting to see how it works. Heating it is not a good idea. It could melt the O-rings
and you know what happens then. BTW you will need a bottom tap for the spark plug
side as that is a blind hole. The exhaust side is a through hole so any helicoil tap will
work. There are only two oil pan bolt holes per rotor housing so you need only
four helicoils.
Paul Lamar ...No rotor no motor.
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