Chasing stud hole...some shavings normal?

[porschett]

I was supprised to see quite a bit of shavings when I chased the stud holes. Thought I clean out the lock-tite and gunk in the threads before I put on my new ARPs.

Should I even have done this?

[kstylianos]

Did you chase with a tap or a 'thread chaser'?

A tap is designed to cut where a chaser just cleans out the crud. If used gingerly, a tap 'should' work ok for this purpose also.

Insert a stud w/o any locking compound and see if if there is any play when threaded to its correct depth. If not, you are probably ok.

[porschett]

Man, I tapped it. I did check the play on the tapped vs. non-tapped (other half of the case untouched). When bottomed out (haven't torqued it yet), they both have similar play.

I don't know what I was thinking. I'm leaving the other half alone. God I hope I didn't mess this up.

[adomakin]

I did exactly the same thing. I sourced a m 10x1.5 tap as per the book and got stuck in. a fair anmount of shavings were coming out so i stopped and tried another hole (please dont ask me why) with the same results. I must have gone down at least 3/4 of the depth of the hole...anyway, tried a (supertec) stud in the tapped threads and they felt loose. that was when i $**** my pants. I phoned Henry at supertec (top bloke by the way) and he advised me that you only have to run a chase throught the threads if they are really crudded up with loctite. I purchased a loctite product for glueing my piston squirters in that can cope with larger tolerances than 574. it is a very high temp stable product and we both agreed that i should use that on the threads. they felt ok when i was installing the studs with the loctite on and have gone rock hard so Im hoping that will be sufficient......

hope this helps

[darkbeer]

"chasing stud hole...some shavings normal"

aren't there web sites for this sort of thing ????

[adomakin]

how very dare you!

[porschett]

"chasing stud hole...some shavings normal"

aren't there web sites for this sort of thing ????

======

LOL. Shavings the norm here in Socal


Thanks Andy for the tip. Are you referring to the loctite 271?

How long has it been since you've installed it?

I torqued one of the studs to 135mm w/o loctite and it seems to be tight with no play. I'm hopping that with loctite, it'll be good.

To get 135mm height, the studs didn't need to be torqued down that much. This was true for also the non-tapped case. Does this feels about right ?

What is the worst case scenario? Case-savers? Helicoil?

[Gunter]

porschett: I assume that the tap had the right pitch?
There is no "torque" needed to get the studs to 135mm; they should go hand-tight to the bottom. I found that bottoming out did not always get 135mm; on some I had to go back a little.

[porschett]

M10x1.5 pitch.

If I'm using the ARP set, they don't have barrel nuts, instead they use tripple square nuts. So I think the height may not be an issue? If true, I was going to bottom out all the studs to 'build up' some tension. This along with the loctite, I'm praying it's enough.

Still kicking myself.

[adomakin]

this is the stuff i used to install my studs. im still building the engine so i can't tell you how it has worked yet but they went in real nice and have gone off real well

[porschett]

Thanks for the link. I like this feature of Loctite 640:

LOCTITE® 640™ is designed for the bonding of cylindrical
fitting parts. ... Typical applications include ... eliminating
backlash in worn assemblies,...restoring the fit to worn assemblies or out of tolerance parts.

So what's the difference between a retaining compound (640) vs. a thread locking compound (271)?

[adomakin]

dunno, but i reckon it looks like a better product to use in this particular situation

[porschett]

OK. I feel better now that I reread Wayne's book. He did mention chasing the stud hole with a tap. But regardless, I'm leaving the other half alone.

[adomakin]

thats how i got to this situation-i read it in Waynes book. im pretty sure he doesn't make a distinction between a tap and a chase but......

[1972_911T]

Ive just done my head studs on my 3.2, to clean out the old loctcite all I did was to screw in an old stud with lots of oil on it to lube up the threads, then cleaned out the oil with some alcohol so the loctite would hold and most of my new studs screwed down to the right hight by hand.

Steve

[adomakin]

one plus point with the supertec studs is that you dont need to get a correct height on install.

[porschett]

Actually, Wayne's book specifically states using a tap.

P.127

"Take an M10x1.50 tap and carefully thread and remove it from each of the head stud holes...The gole goal of chasing the threads with the tap is to remove any old Loctite or Threadlocker..."

Wayne's book hasn't steered me wrong yet, but I'm questioning this method...Wish Wayne can chime in.

[adomakin]

I know where you are coming from tt, i think its a valid point too as at least two of us have fallen foul of this....

[kstylianos]

One can make his own 'chase' by using the same diameter/pitch bolt as the threads and cutting a relief down its axis. You can probably use an old headstud for this purpose. I (personally) don't like the idea of using a tap for chasing as one little whoops, and you could be SOL.

The top 'chaser' shows a good example of the relief needed.

[mark '87 930]

old thread, I know.

porschett, what did you do with the case half that you used the tap on? Did the loctite work and was there ever any leaks?