Head Gasket Replacement

[blazingspider]

Taking the time to clean the head bolt threads and chasing the head bolt holes are definitely worth the effort. Re-used head bolts will stretch over time. I don't have the stock height of a head bolt at hand but at the minimum, you should measure them all to see if they are all the same length. When installing the head bolts, I only use a light coating of oil on the threads. I've never used a thread sealer. Also remember to torque in 3 passes and follow the bolt sequence pattern. I also re-torque the head after 500 to 1,000 miles or so. Good luck!!

[ORFORD2004]

This engine is absolutely stock (and auto tranny!), so I doubt that I'd need studs,...

Ok but if you broke a bolt like i did torquing to 61 lbs-ft, you know that you have a solution.

[wetminkey]

blazingspider,...if you only use oil, don't you get coolant leakage from the threads that enter the coolant chambers?
Yeah, ORFORD, ask me about breaking a 90ftlb bolt down inside my Mustang's engine,...!
Hey, ORFORD and geospider! Tell me more about stud installation,...are they Loc-Tite'd into the block threads? Blue Loc-Tite?
Gotta wait for tap, might as well investigate in the meantime,...
Thanks, guys! Enjoy your weekend!

[ORFORD2004]

Thread sealer for me

[wetminkey]

Yeah, I think I'll use thread sealer,...any threads that enter pressurized passages.
ORFORD,...how did you install your ARP studs? Did you use Loc-Tite to secure the studs in the block?
I think you guys (and my reasoning) have talked me into head studs,...

[ORFORD2004]

Thread sealer for the studs and the ARP grease to torque

[wetminkey]

So,...asked geospider the same thing: how do you keep the stud from turning while torquing? Or worse, how do you keep it from rotating as you loosen the nut?
Allison's studs have a hex in the top of the stud to hold it while tightening the nut. But my torque wrench would not allow me access to the top of the stud while torquing. Neither will my ratchet/sockets,...
This is why I question installing studs,...I don't know the answer to this question.
Todd.

[geospider]

the studs hold from what I understand, all tightening in same direction. Used often, on many applications.
Torque is torque. simple, but that's how I go.
from what I remember, you put a nut on the stud, flush with the top, then screw is in to semi-tight, then would torque down to spec. used thread sealer for the stud and put some oil on the threads for the nut.

all I got

geo

[wetminkey]

I got more,...!
Did some searching,...watched an ARP video.
And found Loctite 1158514,...which seals the threads, locks the threads, and allows for easy removal. Intended for head bolts that penetrate into water jackets.
ARP uses molybdenum assembly lube for the nuts (and I have some!).
I'll order up the stud kit from Allison's right away. I see that NAPA has the Loctite,...
Thanks George! And dinghyguy, and ORFORD!
Now all I gotta do is remember how this thing goes back together,...!

P.S. Unfortunately, I took a couple of years of physics, and yes, torque is torque. But friction is friction, and damned if it won't OPPOSE torque! Miserable stuff,...!

[blazingspider]

blazingspider,...if you only use oil, don't you get coolant leakage from the threads that enter the coolant chambers?

Nope never had an issue with coolant weeping up through the head bolt threads. It is my belief is that you get a more accurate torque reading using just a light coating of oil.

[spider2081]

I think I'm a little late entering this post.

I think I'll buy a new tap to chase the holes,

It's my understanding there is a difference between a "thread chaser" and a "Tap" A tap is a cutting tool and can remove metal from good threads while cleaning them. This weakens the threads and makes them easier to be stripped when the bolts are torqued. A thread chaser is not a cutting tool. It is designed to clean threads without damaging the threads themselves.

Also Its my understanding the head can not be removes with head studs in the block. For future head removal the studs might have to be removed if the head is to be removed while the engine remains in the car.

[ORFORD2004]

I'll order up the stud kit from Allison's right away.

Or you can call ARP bolts with your dimensions and they make you a kit that is cheaper.

[ORFORD2004]

Allison's studs have a hex in the top of the stud to hold it while tightening the nut

ARP also. But you use 12 points socket for the nut so no place for the hex key.

[wetminkey]

Yes, just a light coating of oil will make it easier to torque a bolt, but I believe that proper torque is to be accomplished on a dry thread. Lubrication may cause the bolt to be overtorqued,...And I do believe that Fiat head bolts are supposed to be thread sealed, due to the fact that they enter engine coolant chambers.
The 'tap' is from AutoRicambi and is meant to chase head bolt holes - so it's truly a chase, and not a tap,...but they call it that. The terms are loosely used and interchanged often.
Yeah, I checked ARP (I've got full engine bolt kits on my musclecars) for Fiat Spider and found it not available, so I bought Allison's set. It's OK, ARP has made plenty of money off of me prior to this,...!
And head removal can be accomplished as usual after stud installation. The studs can also be removed with hand tools, even with the head in place,...
I'll post more as parts come in, and assembly is underway. I'll also spend some time explaining WHY studs are a better option than bolts (IF done properly!). Gives me something productive to do with all that damn physics that I learned at Colorado State,...

[18Fiatsandcounting]

Can't wait until it's all back together and running!

Meanwhile, just a philosophical question from me on replacing the head bolts. The 10 head bolts are pretty robust and meaty, so does 61 ft. lbs really stretch them that much? I mean, this isn't really a lot of torque. Sorta like putting a large cat (20 lbs) on the end of a long (3 ft.) breaker bar. If they were torqued to 150 ft lbs, I might imagine them stretching, but 61 ft lbs is quite a bit less than your lug bolts, or suspension bolts, etc, etc.

Am I just frugal (read: cheap), or do the head bolts really stretch beyond their elastic limit and into deformation and thus need to be changed? Or does it have to do with the fact that the cylinder head gets hot/cools down, over and over?

-Bryan