Fitting new head studs

[Jono]

Okay so what is the script here?

I was just going to fit them to the block and nip them up. However Des Hammill reckons it's best to use threadlocker, turn them fully home, back them out 1/2 a turn and then immediately fit the head and torque up (the rationale being the studs are locked in place and have metal to metal contact when the nuts are tightened).

I must confess if I had not read this I would have 1) chased out the treads and cleaned them 2) fitted the new studs with a smidge of copper grease and nipped them up with 2 nuts 3) fitted and torqued the head.

But what is the wise counsel of this August forum?

Jon

[Spider]

I have read Des's suggestion. I have never bothered and while for the most part, IMO Des makes a lot of sense, this is one thing I can't see any value in.

I have always taken the top two or three threads out (counter-bored with a 10 mm drill) and fitted the studs, checking any for wobble and binning any that do (they are a candidate to break). I screw them in hand tight then nip them just so they can't be undone by hand. I only do this so at a later time, when removing the nut, the stud stays put.

[carbon]

I have read Des's suggestion. I have never bothered and while for the most part, IMO Des makes a lot of sense, this is one thing I can't see any value in.

I have always taken the top two or three threads out (counter-bored with a 10 mm drill) and fitted the studs, checking any for wobble and binning any that do (they are a candidate to break). I screw them in hand tight then nip them just so they can't be undone by hand. I only do this so at a later time, when removing the nut, the stud stays put.

I'm with Spider on this one, I have never used threadlocker when fitting head studs into the block. Also when chasing out the threads I just use a 3/8 UNC bolt, very wary about using a tap as any removal of metal will just make the block weaker.

[Jono]

Thanks guys, these are Minispares competition studs so I should be okay?

Would you use any copperslip?

Whilst I'm on I note that the end stud and bolt holes go into the waterway (11 stud block). Should I theadlock or seal these ones to prevent and water ingress between the block/head interface?

Jon

[Lakeland997]

Thanks guys, these are Minispares competition studs so I should be okay?

Would you use any copperslip?

Whilst I'm on I note that the end stud and bolt holes go into the waterway (11 stud block). Should I theadlock or seal these ones to prevent and water ingress between the block/head interface?

Jon

I don't see any value in copper grease here as I don't think the studs will get stuck in the block when they are fitted as above.
I would definitely recommend theadlock (or even better thread sealer if you can find it) on the stud/bolt if they protrude into the water jacket. I had water seepage from around the stud at the water pump end when I failed to seal it. The water won't get between the block and head as the gasket will prevent that but it bubbles out around the nut/bolt head when the engine's hot.
If you don't do it now you'll have to partially drain the system later and it's hard to get the threads clean/dry enough for the sealer to work.

[ianh1968]

I only wind the studs in with my fingers...
... imagine a BOLT in a blind hole...

You don't wind this in until it bottoms out in the hole or else runs out
of thread at the top, do you? The overall fixing should tighten up on the
helix of a thread, i.e., the nut, not the lack of remaining thread at the
bottom end. I don't care if a couple of studs come out when undoing
the head nuts.

I also had a stud break once and it was quite easy to get back out
using a centre-punch by tapping it gently round anti-clockwise.

I do grease them, just normal "LM" grease, but have to watch out for
the hydraulic effect. I wind them in by hand, leave them for a few
minutes, then wind them in again, by hand. I then wipe up the surplus
grease that has been squished out.

Whilst I'm on I note that the end stud and bolt holes go into the waterway (11 stud block).
Should I theadlock or seal these ones to prevent and water ingress between the block/head interface?Jon

On my Marcos block, I got a 3/8" UNC bolt and put a saw cut in the end
of it. I then sawed it off about 1/8" inch long and wound this into the
stud-hole first with a good dollop of Blue Hylomar using a screw-driver.
I had to shorten the stud very slightly, but there is plenty of thread length
remaining. This cured my "weaping stud" problem and I don't have to
drop the water to re-seal this every time I take that stud out.

As Spider has said on here before, the reason for either a counter-bore
or at least a decent chamfer in the top of the hole is to stop the studs
from pulling a high spot in the deck which can lead to head gasket problems.
Again, Spider has previously reminded us that running an oil-stone across the
top of the block prior to fitting the studs is a very worthwhile part of the procedure.

Ian

[Jono]

Top tips, thanks guys.

I'll post up some pics of the build, now that I'm ready to start the enjoyable bit.

It's a meticulous process and it's easy to appreciate why this costs so much to get done by one of the pros.

Jon

[carbon]

On 11-stud set-up the '11th' stud nearest the water pump should be a bolt, this has flanged head and uses soft alloy or copper washer underneath to effect the seal.

Don't use threadlock on this one, and only take up to 25 ft-lb max torque as the thread is 5/16 UNC.

[Spider]

Ian, that's a but of trouble you go to to seal up the bolt hole, but I can see method in the madness for sure.

On 11-stud set-up the '11th' stud nearest the water pump should be a bolt, this has flanged head and uses soft alloy or copper washer underneath to effect the seal.

Don't use threadlock on this one, and only take up to 25 ft-lb max torque as the thread is 5/16 UNC.

I'll just add to carbon's post.

Even if the Bolt has been 'converted' to a 3/8" Stud, I wouldn't suggest using more than 25 ft / lb torque, the deck's not what I'd call 'beefy' around where that one goes.

[ianh1968]

Ian, that's a but[bit?] of trouble you go to to seal up the bolt hole,
but I can see method in the madness for sure.

Five minutes with a hacksaw and a blob of goo...
... not exactly "trouble" to get it waterproof on a fairly permanent basis.

It was the best "plan" I could come up with at the time,
and it turned out to be very successful!


The real "trouble" could be doing it the "proper" way and sealing
it at the top with a soft washer when general corrosion of the bolt/stud
into the block sets in. Stopping the water at source should prevent this.

I've experienced similar issues with thermostat studs in heads.
Plumbers PTFE tape on the threads and goo was the solution
that I used on a Morris Minor a while ago. Anyone that's tried to
remove a seized on 'stat housing will know what I'm on about here!

Goo is Good!

Ian

[Spider]

Goo is Good!

Ian

I'm with you on that!

Yes, I'd prefer to 'stop it at the source'. While Carbon's suggestion of a copper or allow washer is a good one, it's not one I think I'd do for a few reasons, I've always sealed the bolt on the thread in the deck.

Goo is good!

[Jono]

I've built a few Lotus TC engines and goo is the accepted way to go with the water-pump housing bolts (and boy can these engines leak if you don't follow the rules to the letter, been there done that) The Loctite grey for water and the Loctite black for oil.

I am going to use some grey on the end bolt and stud on the Mini engine. It feels like a bodge but it works on a TC so I can't see why not on an A series.

Cheers, Jon