355 head gasket; re-useable?

Replace the mate. They have been crushed by an incredable amount of force that have compressed the raised sections to seal around the cylinders, water /oil ways.
Re using them MAY work but for how long?? Have peace of mind brother

 

High torque specification + Incredibly important function + High internal pressure = REPLACE

Just my opinion, but I am certainly no expert!

 

Typically reusable (I have stripped them before, not on a 355) I typically clean and lubricate threads with 30wt oil when assembling.

 

As a rule yes the nuts as well. They don't cost much so just do it.
I don't mean to sound condescending sir. But i find it a tad disturbing that you are doing some thing as major as a pair of F355 head rebuilds with out knowing basic engine building procedures like not re using head gaskets and stretched head nuts.
I assume you are referring to using the standard nuts that you originally took of the engine in the first place, and then used them again until your little problem, and now has crossed your mind about considering using them for a third time?
Even head studs should be replaced technically, but even if re-used they can only be stretched so far. That's probably why the thread striped in the first place.

 

Like I said, I'm no expert, just an anal retentive with OCD.

 

Speaking of gaskets. What do you guys like for gasket replacement? I love Honda-Bond and Hylomar (sp?). In small, very carefully applied amounts, of course.

 

You do come across as condescending.

Head studs don't normally get replaced unless they are the "torque to yield" type. Nuts are on a case by case basis.

 

Not on a head gasket.

 

Thanks, Tim. I know. After I posted I said to myself - someone is going to think I meant for the head gasket. It was too late to edit. It's totaly my fault for not being clear. I'm new to FChat (06/2008; 400+ posts), but not Ferraris (this is my 4th). I've done most of the interior/exterior/mechanical work myself. With the exception of "shooting paint" and gear boxes. "A good man knows his limitations". Inspec. Harry Callahan. I did open up my ZF box on my 328 once, I became very, very scared and buttoned her back up! I'm certainly not a professional like you, Dave, Alex, Brian, et al., but not a complete moron (well, I don't know if that's accurate).

Seriously though, I don't know if I would go with the OEM head gasket. What do you guys think of those new kevlar/polymer/copper-combination composite head gaskets? I think they have them for F355 and newer Ferraris. I'll have to dig-out the source. How about copper alone?

So, what DO you guys like for gasket replacement? Maybe this should be in a separate thread.

 

Ok thanks for that expert Yea reuse your nuts as many times as you like Tim, its not really false economy even though they are all on there 3rd torque cycle. Its a great idea I would change them personally but thats just me.
Still worrying me how the question of reusing a head gasket from a guy who is rebuilding a Ferrari engine though. But as i always say, hey what do i know. ask 2NA he may be able to put the question another way thats a little more gentle and less condescending

 

It was a fair question regarding the gasket. It hadn't been through any heat cycles yet and would likely take another few days to replace, why not ask around and get some input?

The amount of work (and another new timing belt) required to replace it again later when it doesn't seal well, makes it a rather foolish way to cut a corner.

 

I side with Tim here on the condecending. I dont believe the OP needs be accused of not having basic skills for asking a simple and intelligent question. The headgasket was never used, it was simply clamped down and released. And while its not really worth the risk of reusing it given the amount of labor involved should it prove otherwise, it would have worked just fine and lasted just as long either way.

I am not positive about the 355, but all the cars previously replacing head studs from these engines is NOT recommended. These arent stretch bolts that yield under tension, they are hardened studs. Too many have been broken off in the block trying to remove them that the wise among us leave well enough alone. Break one off and you risk destroying the block trying to remove it. I dont know of anyone in all the years I have been reading, watching and listening who has ever recommended they be replaced. Again, the 355 may have yield studs, and if so maybe they are meant to be replaced, but IIRC those began with the 360/430.

And the stud most likely had nothing to do with the nut stripping, either. The nut is softer material than the stud, and for good reason (see above). As long as the nuts thread on okay and torque down, they arent going to suddenly rip out after the motors together. So while it might be a good idea to replace them all as a matter of course, its really not mandatory, and in no way justifies speaking poorly about a mans abilities.

I dont know your abilities, but I have known Tim (2NA) for quite some time and I would rate his mechanical expertise at a very high level. Tim has worked on Lamborghinis for many many years, from Miuras to Countach's, the occasional Ferrari, and myriad other machines, and you can trust his knowledge. I think that far too often there is the idea that all the parts that come off need to be replaced, but in reality we still find ourselves with budgets and time constraints that take precedence. Nothing is perfect, and it will never be perfect, the best we can hope for is simply to slow down the process of decay. And by now, Im sure the OP feels about the same as I did talking about my brake pads. Better to remain silent, and thought a fool, than to speak up and remove all doubt? If people keep getting thier hands bit for asking reasonable question's, the knowledge pool is going to dry up.

 

Like i said, i was wrong ok? Sorry if i came across as condescending ok?
Re-use it all, its all good? Even the soft stretched threads of the nuts and the crushed gasket. Its all good. Happy now? Is that good?
No problems here so there's no need to jump on any ones band wagon talking about my being condescending. I was wrong very very sorry. What more do you want me to say.
Thee 355 engines that i have built have always used brand new gaskets and even nuts. But thats just me.

 

Ive done lots of rebuilds on various engines so I'll chip in.

Head Gasket, I would replace if its just a matter of spent time, it not been through any heat cycles as someone already said, or settled so it "could" be ok, but I wouldnt use it long term.

On a previous car, I had a show the next day, right at the end of the day before, I just finished doing some work that required the head off over the previous week, putting it back together and I had to take the head back off (forgot to plumb an oil feed from block on for a turbo, impossible to do with it on). It was late and no way to get one till the following week, hadnt been started, but HAD been torqued.

I wasnt gunna miss the show and drag the next day, it held up, had hard boost all day heh....however, the next week, I got a replacement and replaced it, on the gasket you could see where it wasnt sealing properly, not enough to cause a leak, but pockets where it had lifted.

Basically, if you need it for a week and you baby it, you can use it, if not and you can wait the extra time, replace it.

As for the bolts, measure all the ones that you know should be equal length, if they are yeild bolts, then there will be differences in the sizes by a good amount and may need replacing. If they are within 0.5mm (maximum) of each other, then they are not yeild.

 

Re-use the gasket AND the studs/nuts!

 

Well stated!!!

Hey Pap, I stole this from you. Ha Ha!!!! Thanks!
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Hey, no worries mate.

I stole it from someone else.