drill bits and taps

[Akane]

I'm trying to recoil / helicoil my head, I'm having trouble locating a "12.8mm drill bit", it's a weird size yes, but I cannot use anything else or else I risk not able to cut enough threads out of the existing one.

And I am looking for a M14x1.5 tap, just that, I don't need a whole expensive set of taps, I just need that 1 tap, which is appearntly "a huge size and we don't stock these" kinda things.

If anyone can point me in the right direction i'll greatly appriciate it.

Thanks.

[Jebus]

I got a 9.7mm drill bit from Tool & Engineering warehouse in Papakura, look them up and give them a call, id put money of them having one.

[atmosports]

Trade Tools, best bet for the vast majority of drills/taps. M14 x 1.5 is standard metric fine & not huge, as for a drill if your using that tap above a 12.5 or 1/2 inch drill would work fine.

[Spannergal]

when we're doing helicoils in the workshop, we just use the closest in size for drill bits eg 12.5 or 13mm

[evil_si]

trade tools in pensose will be able to sort ya out.

[Akane]

cheers guys, I'll give them all a shot tomorrow.

[Stu-]

Wairau Engineering Supplies too.

[Akane]

Thanks Stu, I gave them a call, i'll go around to pick it up in the weekend or early next week.

[Ganjasaur]

Is it true that your torque settings can change after you have used a helicoil? I thought this was why most good engine reconditioners use solid tread inserts.

[Akane]

Well, as far as I know, the helicoil/keysert/insert/(whatever you like to call it), will be at least as strong, if not stronger, than the original thread.

What I think is, is that the thread will be bigger and larger on the outer sleeve, hence more "Grip", and when used in application like this (damn Gen 1 soggy aluminium head), it'll be stronger because this is made out of Carbon Steel.

Pity they cost the earth (I bought a set of 4 for $65), or else I'll do all 7 of the holes (providing that I know what I'm doing and don't screw anything up).

So far I've:

Helicoil - set of 4: $65
new set of stud and nut: $85

the parts i'll need:
angle drill: $250+
bit and tap: $65

Oh my god, only if anthonym stop stalling and reply my e-mail, it would've been so much cheaper to just replace the head and replace the headgasket.

[fivebob]

Why such a large tap?

The studs are no where near that big, so what sort of butchery are you planning to perpetrate?

[Akane]

The outside diameter of the keysert needs a M14 x 1.5 thread. These are already your "Thinwall" keysert series.

I was scared that there's not enough meat on the head, but it's either this, or nothing. Worth a try.

[fivebob]

IIRC the exhaust studs are 10x1.25, Intake are 8x1.25, and the helicoil set for 10mm uses a 10.25mm drill bit and a 12mm tap.

The sizes you quoted make no sense if you're using a helicoil/recoil

**EDIT** I see you're planning on using Keyserts. they require a far larger hole. If it was me I would just use helicoils, much cheaper/easier and they will not require such a large hole.

[Akane]

These are alright bought, too late to make a change now.

Saeco recommended these as they're "very strong"

[vvega]

Well, as far as I know, the helicoil/keysert/insert/(whatever you like to call it), will be at least as strong, if not stronger, than the original thread.

What I think is, is that the thread will be bigger and larger on the outer sleeve, hence more "Grip", and when used in application like this (damn Gen 1 soggy aluminium head), it'll be stronger because this is made out of Carbon Steel.

Pity they cost the earth (I bought a set of 4 for $65), or else I'll do all 7 of the holes (providing that I know what I'm doing and don't screw anything up).

So far I've:

Helicoil - set of 4: $65
new set of stud and nut: $85

the parts i'll need:
angle drill: $250+
bit and tap: $65

Oh my god, only if anthonym stop stalling and reply my e-mail, it would've been so much cheaper to just replace the head and replace the headgasket.

i know of a gen 2 head for sale
pm all fours for details

v

[vvega]

These are alright bought, too late to make a change now.

Saeco recommended these as they're "very strong"

they are very strong but probably not best for you application

v

[fivebob]

These are alright bought, too late to make a change now.

Saeco recommended these as they're "very strong"

But you don't need verg strong inserts if you torque the studs to the correct values helicoils are more than sufficient, and I'd guess for the price of the drill bit and tap that still need to get, you could get a kit to do all the holes.

BTW which studs are you repairing? The inserts you have are only good for fixing the intake studs.

[Akane]

I PM'd all four's already, but his one is only a 7 stud head, I prefer my next head to be a 9 stud Gen 2 head again.

fivebob, what do you mean by only good for the intake side? I'm doing the exhaust side. MC Racing tried to "Fix" it, and end up stripping another stud.

[fivebob]

Nevermind, I read the table for heavy duty inserts not the thinwall ones

[Akane]

Anyways everything's back together and running now.

I'm gettnig boost a few hundred RPM's earlier

But there's still a HUGE air leak, due to me not drilling the Middle bottom hole deep enough (I was really scared of drilling too deep), and I didn't take the tap's top bit where's there's no thread into account, so there's not enough threads. This resulted in the keysert not going deep enough and it's not sitting flush, it's sitting about 1mm out.

I'm going to "trim" the gasket around that stud and hopefully get a tighter seal. The head's going I think, when cold I can hear the valvetrain chatter quite a bit, and felt the vibration.