Head bolts

carl

carl

True Classic
While I have rebuilt more 124 motors than I can count, I have never had an X motor apart...until today. I pulled apart the 1500 that came with the Fatrat and everything checks out OK to use as my new motor. I will do new rings, bearings and seals but I seem to recall that the head bolts can't be reused? Or maybe they can? Can someone set forth or point to a thread that discusses X head bolts so I know what to do. This is an FI 10 bolt motor. Most of the head bolts made a satisfying "snap" when I loosened them but a few just spun loose without making any noise.
 
Head bolts on the X1/9 have been a journey. All studs, then 5 studs/5 bolts, then 19mm headed M12 bolts in both straight and necked varieties, then 17mm headed M10 bolts/stretch bolts aka torque to yield, then 14 head bolts....geez it's enough to give anyone a "head" ache!

Since there are several possibilities, best to post a pic or info about what the engine had in it.

As we have learned from Steve in Australia (fiatfactory), best to consider headbolts and your head gasket as a system: since there were so many permutations, the head, the bolts, and the gasket need to be the right combination.
 
The bolts Obert and MWB sell can be reused, as long as length is unchanged - you can typically see the thread change on a bolt that has stretched. If the bolts have that step/chamfer in the shank area, they are likely TTY bolts, in which case it is usually unwise to reuse them, esp given they are now 30+ years worth of heat-cycling. Whatever you end up using, follow the annoying re-torque for whichever bolt / gasket you buy.
 
Head bolts ( I didn't realize they are two different lengths depending on what side of the head they are on) have 10mm threaded shank with a reduced 9mm shank portion above the threads. They also say 10R on the head.
 
carl said:
Head bolts ( I didn't realize they are two different lengths depending on what side of the head they are on) have 10mm threaded shank with a reduced 9mm shank portion above the threads. They also say 10R on the head.
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The thinner shank suggests torque-to-yield. When I encountered a set of these I replaced them with new bolts of the appropriate length and grade bought from one of the regular online vendors of metric hardware... no idea if that was necessary, but it seemed worth a few tens of dollars not to have to worry about it.
 
Your description sounds like the "TTY" (torque to yield) type bolts. I think I would be of the same opinion as Huss and not reuse those. It's my understanding they stretch (the reason for the skinny middle portion) to provide the TTY function. And that makes them pretty much a 'one time use'. Plus using new bolts may improve the odds of a successful head gasket replacement. And like Dan said, Steve C has provided information about how the different types of bolts correspond to different types of head gaskets. So if you buy a new gasket and new bolts, make sure the two are a compatible system. Or you can switch to studs and use any head gasket you prefer. There is another recent thread on that topic.
 
What a crazy system for a production motor. I'll check with my go to X parts vendor and see what he suggests for new gasket and head bolts. I try to keep things simple, it would be nice to be able to drive the car this summer.
 
carl said:
What a crazy system for a production motor. I'll check with my go to X parts vendor and see what he suggests for new gasket and head bolts. I try to keep things simple, it would be nice to be able to drive the car this summer.
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To be fair, each change was a product improvement. For example, going from studs to bolts was to avoid the head-stuck-to-block syndrome, going to stretch bolts plus the Astadur head gasket was to avoid the retorque hassle, going to 14 head bolts was to correct an oil seepage problem (that did not seem to be a big issue with the SOHC in X1/9s), etc.
 
another source of bolts is Bielstein. I believe these are the early M12 reusable types.
https://www.bielstein.com/Head-bolt-set-12-mm

Can someone make a table of which bolts go with which gaskets? I snippet here and there makes it very difficult to memorize. If this is pretty coherent this thread could be saved for easy future reference.
Engine - head bolt - gasket - retorque y/n
 
Dan Sarandrea (Phila) said:
To be fair, each change was a product improvement. For example, going from studs to bolts was to avoid the head-stuck-to-block syndrome, going to stretch bolts plus the Astadur head gasket was to avoid the retorque hassle, going to 14 head bolts was to correct an oil seepage problem (that did not seem to be a big issue with the SOHC in X1/9s), etc.
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Yep - changes of this sort are to be expected in a long production run, and the Fiat SOHC has had a long run indeed. Something similar happened with the Porsche flat-six.
 
The headgasket was a monster, very thick and stiff with a red line around the perimeter. Said "no retorque" on it.
 
carl said:
The headgasket was a monster, very thick and stiff with a red line around the perimeter. Said "no retorque" on it.
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Good luck finding a replacement of that style. All the ones I've seen here are standard re-torque, as are the US supplies of head bolts. I considered buying HG from EU hat was described as "astadur (sp?)", but the vendor then said the bag was split. You do not want a non-retorque gasket that is old stock/open. They have a limited shelf life once opened. That is my experience with Volvo version, don't see why it would be different for any other.
 
lookforjoe said:
Good luck finding a replacement of that style. All the ones I've seen here are standard re-torque, as are the US supplies of head bolts. I considered buying HG from EU hat was described as "astadur (sp?)", but the vendor then said the bag was split. You do not want a non-retorque gasket that is old stock/open. They have a limited shelf life once opened. That is my experience with Volvo version, don't see why it would be different for any other.
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Hey Hussein, look what turned up on eBay Italy that might fit your setup...https://www.ebay.it/itm/Fiat-Punto-...-Multi-Layered-Steel-Head-Gasket/254185936817
 
That head gasket (tipo) has an extra hole in it compared to an X19 head gasket.... tipo head has a water passage there, and when fitting tipo head to an X19 (closed deck) block I use an X19 type gasket, which simply covers the hole.

If tipo gasket is used on an X19 block... there's an open hole in the gasket for no reason, not being fully supported, and possibly a point of failure should anything not be 100%.
s-l1600_LI.jpg

plus it's a 14 bolt and Jeff is looking for a 10 bolt.

SteveC
 
carl said:
The headgasket was a monster, very thick and stiff with a red line around the perimeter. Said "no retorque" on it.
Click to expand...


That sounds like a Fel-Pro gasket.

A sharp "snap" when undoing bolts is good... that means they have held tension... no "snap" is bad... and in the case of TTY bolts often will mean they have deformed and are only good for the bin... this is what you see when TTY bolts are re used.

I'm assuming, of course, that the sequence of undoing the head bolts was in torque sequence order.. and not just from one end to the other... and the bolts that didn't "snap" where they the middle two? this would indicate that the head gasket was on its way out and had lifted..

and BTW I have loads of OE astadur gaskets to suit the ten bolt M10 engines
https://www.ebay.com.au/itm/Fiat-X1-9-X19-Ritmo-Regata-1500-SOHC-head-gasket-Genuine-Fiat-5951682-Astadur/332314212418

SteveC
 
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This is a stock motor internally and will be driven in my urban street environment. I'll go with whatever head gasket comes in the MWB engine rebuild gasket set and whatever head bolts Matt recommends. While it's fun to talk about getting unobtainium head gaskets and funky bolts, for my use that's more bragging rights than a quality of parts needed for my situation. If anyone here feels that something better is actually needed, please feel free to state here....and why.

Steve, in one of my more lucid moments I actually did undo the bolts in reverse order.
 
While on the topic of head gaskets. My wife has a very impressive programmable die cutting machine, which can cut up to 14-12ga metal. Using an OE gasket template or scan of full size factory drawing; a copper gasket could be replicated. I plan to do this with a carburetor gasket set, but an HG seems like a different animal.
If doing this A: What gauge copper should I use? B: would some type of flame ring be needed or is the copper good as is?
 
Not to divert too far away from Carl's needs, as he does not need a MLS gasket for his engine. But if anyone is interested in a MLS head gasket, it has been confirmed that Cometic is producing them for both the 10 and 14 bolt engines (any thickness desired). And for what it's worth, Cometic also offers copper head gaskets. Personally I'm not a big fan of copper heads gaskets though.
 
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