May Day May Day ( hey it's september)

[vigman]

I stripped a stud in my 327 engine...see Mystery 327 next gen post!

HELP!!!!
Plueeze!

Vig!

 

[rpounds]

Oh man Vig!! What a rotten thing to have happen. Makes me wonder a bit . . .

I have no idea of the torque capabilities of Helicoils. Maybe someone with specific knowledge (maybe JohnZ?) will jump in here.

However, is there enough room in the cap to drill it out to a larger size and then drill and tap the block? Without good tensile and torque data on Helicoils, I would be a little concerned about them holding up in that application, especially at high RPMs. Could be wrong . . .

Another suggestion - have the block drilled and tapped for thread inserts. I'm talking about the type of insert that is marketed by Reid Tool Supply company. You can find these inserts at McMaster-Carr or most any other industrial supply house. Rather than a Helicoil type of insert, this is a solid steel sleeve that is threaded on the ID and OD. You can drill and tap the block for the OD thread size and then install the insert with permanent Loctite.

Just my 2 cents and 3 ideas . . .

Ron

 

[Nut]

Mike.... send sscam69 a pm. He's a mechanical engineer and would probably know. I'll check with an ME buddy of mine in the neighborhood tomorrow. I hate when that happens.

......... Nut

 

[rpounds]

I am an ME. Still don't know what the capabilities of Helicoils would be . . .

 

[ErnieN85]

Check out Timeserts.com I think thats it mutch stronger than helicoils

 

[ErnieN85]

Nope didn't work! Thats mthe name but I've lost the link I'll see if i can track it down for you!

 

[ErnieN85]

www.timesert.com\

 

[vigman]

To late....

Went with PERMA-COIL
Stainless inserts ( sorta like helicoil )
the Studs were ( are ) 7/16 X 14

So you drill the block with 29/64
and the nice thing the cap makes a great drill guide.

Remove the cap.

Tap out for 7/16 X 14 [this is labled wrong on the tap...looks more like 1/2 X 14] The insert OD is.5395

Use the insert seating tool to screw the new one in.

Break the tang out of the bottom.

Using a magnet to fish it out ( the tang )

and Voila it's finished!

So it cranked up to 70 ft/lbs with no issue.


It continues.....

Thanks!

Vig!

 

[ErnieN85]

Glad to hear it's fixed!

 

[vigman]

Pix of the permacoil kit

;worship

Thank you PERMA-COIL
23410 Garnier St
Torrance,CA 90505
310-891-1995


Vig!

 

[sscam69]

I duuno the capabilities right off the top of my head on the heli-coils etc..

From the one I installed for my carb stud, I remember it feeling really snug, both the heli-coil and when tightening the stud.

Hey Vig are they splayed?

If it goes I think it would be because of the shear involved.

I would of have drilled, tapped and used the next size bolt tolerances permitting. That way you cut out the middle man, that being the heli-coil.

just my .02, let us know how it goes Vig

Frank

 

[vigman]

Splayed?

As in angled... no straight
the cap wouldn't take opening to the next size without totally weaking the cap.
I will look into the tech issues next ... but so far my engine rebuilder sez OK to do
but dont try to pull 10k RPM LOL!


Vig!

 

[maxrevs85]

if it goes i think it would be because of the shear involved

I dont believe it would fail from shear, shear is a side load. Thread stripping is from over torque or a weak thread.

 

[vigman]

I agree

It would be from the pounding motion/harmonic beating against the cap pulling the threads out of the block casting or backing em out...I'm not really concerned ( crossing fingers ) that the stud will back out
the ARP stuff looks fairly bullet proof. the car will be a street/cruiser not a 1/4 miler.

( with the ocassional rustang romp )

So back to garage I go... but it's hot ( again today ) so I might whimp out.. and my helper ( eldest son ) is still sawing logs at 10:30!


WHAT A BUM...

Hmmmm must be genetic!


Vig!

 

[sscam69]

shear is a side load. Thread stripping is from over torque or a weak thread

:confused

It would be from the pounding motion/harmonic beating against the cap pulling the threads out of the block casting

the car will be a street/cruiser not a 1/4 miler.

Then you should be alright. I mean if a two main can hack about 500hp then why won't 3 be able to hack what your putting out IF the cap goes south. As long as you keep the pounding down and the power reasonable I think you should be alright.

BUT PLEASE DON'T EVER HESITATE TO TAKE OUT A SLOWSTANG!!:L

 

[JohnZ]

Heli-Coils or Perma-Coils will both work fine for this application; don't worry about it. IRL/CART/F-1 engines are full of them.

 

[sscam69]

IRL/CART/F-1 engines are full of them.

:L

 

[vigman]

Not worried

Still building her

Zoom-Zoom


Vig!

 

[sac001]

Not sure of the exact name, but we use Heli-coils on aircraft engines all the time. Should be no problem.

My $.02

 

[rpounds]

Okay, I'm back in the office today, so I had to look up the strength characteristics of Helical Inserts.

According to the information that I have, these things are hardend to 43-50 on the Rockwell 'C' scale and have a 200,000 PSI tensile strength.

Just for comparison, 1018 Cold Rolled Steel (CRS), a very common steel used in manufacturing, has a tensile strength of 70,000 to 85,000 PSI.

Gray cast iron, depending upon the alloy, has up to around 60,000 PSI tensile strength. 6061 aluminum in a T-6 condition is around 42,000 PSI.

What does all of this mean? The helical insert is stronger than most any parent metal you are liable to use it in, including an engine block.

FWIW