Technical 128 Cylinder Head Studs

[Steve128SL]

Does anyone know of a source for the 12mm x 1.25 cylinder head studs on the 128 engine? I need 3 having had to drill out the original ones. I thought maybe the guys in Croatia would be able to help if I knew how to contact them.

 

[renault]

have you tried these people Steve - https://en.fiatclub.eu/login.php?activation=ok

by the way, as a new owner of a 128 there are a couple of little bits I need. Have you any ideas where I should look?
cheers
geoff

 

[The Panda Nut]

I was poking about in Italiparts web site the other day and think they just might help.

 

[Steve128SL]

have you tried these people Steve - https://en.fiatclub.eu/login.php?activation=ok

by the way, as a new owner of a 128 there are a couple of little bits I need. Have you any ideas where I should look?
cheers
geoff

Thanks Geoff, I hadn’t seen that site before so I’ve registered on there now and will try. I have quite a few 128 parts - mostly mechanical bits although I do have a brand new 128 saloon fuel tank which I thought I might be able to adapt to the Coupe but there are too many differences. What parts are you after?

 

[Steve128SL]

I was poking about in Italiparts web site the other day and think they just might help.

Thanks Panda Nut, they have the bolts advertised but not the studs. I’ll contact them to see if they can help.

 

[The Panda Nut]

Thanks Panda Nut, they have the bolts advertised but not the studs. I’ll contact them to see if they can help.

Thought I saw some

 

[124BC1]

Here's a full set of bolts, studs and nuts (in Switzerland) :-

Cylinder Head Bolts Set Fiat M12 128, X 1/9 1972-84 - riAuto

Order Cylinder Head Bolts Set M12 Fiat 128, X 1/9 1972-84 fair priced in the riAuto online shop. OE: 4223901 - 13529330 - 16101521

www.riauto.ch

Or individual studs (from the U.S.) :-

I realise you might not want to pay this much or have to ship from afar but a few suggestions:-

Would it be possible to obtain bolts of the same tread, cut off the heads and thread the plain ends?
Are these studs used elsewhere on other Fiat models?
Have you contacted any businesses that work on these Fiat engines to see if they might have a few to spare (new or S/hand)?
I can't remember the head bolt/stud arrangement on the 128 engine but could bolts not be fitted to replace the missing studs after the head has been fitted

 

[124BC1]

Having thought about it for a bit, I vaguely recall that the studs and head bolts are not parallel? on these engines, so the head has to be fitted over the studs first and then the head bolts inserted? So, maybe bolts could be used after the head is fitted? I also seem to recall that possibly earlier 128 engines had all 10mm bolts used on the head - but my old memory might be failing me... I do remember there were 2 Fiat special tools needed to tighten/ retighten the head fasteners in situ.

Also, given the hardness of the head bolts, it might not be feasible to cut threads on one to convert it into a stud, I seem to recall that the bolt threads might have been 'rolled' into the material at the factory (makes them less likely to fail where the thread starts) just like spoked wheel spoke threads.

I reckon your best (and cheapest) option is to try to find someone who could let you have some used head studs.

 

[renault]

Thanks Geoff, I hadn’t seen that site before so I’ve registered on there now and will try. I have quite a few 128 parts - mostly mechanical bits although I do have a brand new 128 saloon fuel tank which I thought I might be able to adapt to the Coupe but there are too many differences. What parts are you after?

I recently bought a one owner 1979 very original 128 in Italy and there are just a couple of items it needs : 1) passenger door 'rubbing strip' - black trim strip. 2) little oval rubber grommets which cover the holes presumably where the chrome bumper was mounted to the body on older models. 3) screw on clamp to secure spare wheel in place.
These are obscure things, not important but very probably still on a scrapped car !
cheers

 

[Steve128SL]

I might have the spare wheel clamp - if it is the same as fitted to the 128 3p. Is it a large dished washer (to fit the wheel centre) with a sort of wing bolt to tighten it?

 

[renault]

yes, that is what it is Steve
I now realise that I also need a door stay for one of the rear doors

 

[124BC1]

I now realise that I also need a door stay for one of the rear doors

@renault

Have you tried:- https://www.fiatparts.de

This co. lists a 'door check strap' (which is what the door stay is called) @ Euro10 but unfortunately this part is shown as 'currently not available' (an image of it can be found under 'interior/attachment parts).
They also stocks lots of parts for the 128, incl. chrome front and rear bumpers (2 types, with or without rubber strip).

Also -
https://shop.arnold-classic.com/en/fiat/128/doors/ shows a door catch strap @ Euro 24.90 , they also list the plastic roller for the door catch strap if this is all you need to repair a broken catch @ Euro1.79.

 

[Steve128SL]

Having thought about it for a bit, I vaguely recall that the studs and head bolts are not parallel? on these engines, so the head has to be fitted over the studs first and then the head bolts inserted? So, maybe bolts could be used after the head is fitted? I also seem to recall that possibly earlier 128 engines had all 10mm bolts used on the head - but my old memory might be failing me... I do remember there were 2 Fiat special tools needed to tighten/ retighten the head fasteners in situ.

Also, given the hardness of the head bolts, it might not be feasible to cut threads on one to convert it into a stud, I seem to recall that the bolt threads might have been 'rolled' into the material at the factory (makes them less likely to fail where the thread starts) just like spoked wheel spoke threads.

I reckon your best (and cheapest) option is to try to find someone who could let you have some used head studs.

I ended up buying 5 high tensile M12x1.25 bolts (100mm long) then cut off the heads. I bought a tungsten M12x1.25 die and carrier and cut new threads on the cut ends. I did bevel the ends first to make sure the die was running true. A new set of nuts and its all back together now waiting to go back in the car.

 

[124BC1]

Thanks for the update on your solution, doing so may help others with a similar problem in the future.
And well done for managing to manually re-thread the new 'studs',
I know it's not always easy to get the die to start cutting the thread in correct alignment with the stud and you had to do this 5 times!

 

[Steve128SL]

Thank you. Incidentally, the studs and bolts sit parallel in the block. I think the studs are used because when the cam carrier is fitted it overhangs the top of the studs, preventing the insertion or removal of bolts on that side of the head. Once the engine is installed and has been through a heat cycle, I will have to make a cranked tool to in order to re-torque the nuts.