While the head is off

[pope]

The bolts are metal but the head is aluminum. Cant rust together, but the rust on bolt can make it difficult, but nowhere near metal to metal. Welding to a nut works great.

[wengr]

Hello Pope, my problem is exhaust to downpipe studs. going to try the welded nut trick asap.

[wengr]

An automotive machine shop owner today told me that in his opinion since an aluminum head only allows for about .002" or less of irregularity to assure a head gasket seal, he recommends they all be cut as a matter of course. Does this sound right in general and for our cars specifically? or just selling services?

p.s. Vapor trap hose and aux shaft seal added to the list, thanks guys

[pope]

You broke all 6 of THOSE bolts!!!!!!!!!!!!!! Holy SH#%. Good Luck.

[racydave]

You should check the head yourself with a dedicated straight edge, and feeler gauges. Re-surfacing the heads will change the valve timing, and require bigger valve shims.

[wengr]

why would a shave affect the shims?

[racydave]

You're right...

[karhawk]

The bolts are metal but the head is aluminum. Cant rust together, but the rust on bolt can make it difficult, but nowhere near metal to metal. Welding to a nut works great.

Do yourself a favor and have a machine shop remove the broken studs, its very easy to screw up your head trying to get the studs out, and to state the obvious use new studs and nuts NOT bolts. I would pony up for new head bolts as well, factory bolts are supposed to be good for 3-4 uses, but mine would not torque down due to stretching. I ended up using Turbo bolts. While your at the machine shop you might as well have the head surfaced, it only cost me $30 extra.

Chris
Oakland, Ca

[pope]

Chris,
I thought Wengr was talking about his head studs but he was talking about his manifold to down pipe connection. My mistake.
You do know they are called stud bolts.
Most Spider owners dont trust machine shops to work on these car because of too many horror stories and also for the love of it. SoCal Mark and a few others are the only trusted shops.

[wengr]

Most Spider owners dont trust machine shops to work on these car because of too many horror stories and also for the love of it. SoCal Mark and a few others are the only trusted shops.

Is there anything fiat specific I should know so I can avoid potential problems at the machine shop? While the guy I'm considering has years of experience and a decent reputation, there is no one around here that has done a lot of fiats and the few they would have seen would have been years ago.

[wengr]

You broke all 6 of THOSE bolts!!!!!!!!!!!!!! Holy SH#%. Good Luck.

I know it makes me sound like a butcher but I've had a few experiences where you try penetrating oil day after day and they just break anyway. Sometimes the nut comes off and the remaining threads are half gone. It'll be nice to be rid of the ancient rusty crap and have new intalled with antiseize. It seemd like four of them were 13mm, and the other two were 12mm? is this correct?

[So Cal Mark]

they were all the same size at some point. Broken bolts are one of the realities in dealing with exhaust pieces

[baltobernie]

I'd consider comparing the cost of a salvage exhaust manifold to the cost of EZ-outs, Helicoil, etc. work on the manifold, particularly if a machine shop is involved.

6-bolt manifold, bead-blasted and hi-temp painted, six new studs and brass crush nuts; $100 + shipping from Maryland
j.erskine2@verizon.net

[karhawk]

I'd consider comparing the cost of a salvage exhaust manifold to the cost of EZ-outs, Helicoil, etc. work on the manifold, particularly if a machine shop is involved.

6-bolt manifold, bead-blasted and hi-temp painted, six new studs and brass crush nuts; $100 + shipping from Maryland
j.erskine2@verizon.net

That is a sweet deal!

Chris
Oakland, Ca.

[baltobernie]

John is our club treasurer; owns several Spiders and X's plus a few project cars. He's been invaluable in helping me with my restoration; I was there yesterday, as a matter of fact, doing some bead blasting.

He does not have a Web site; I have volunteered to help him with one next Winter. (ps If any of you know of an inexpensive ready-made "store" software package, let me know) But you can e-mail him your Parts Wanted, he has a good inventory of salvage parts that are generally not sold New from our catalog suppliers. Late-model cable accelerator pedal assemblies, for example, which are used to convert early rod linkages.