Fiat Punto 75 SX Cam Belt

If the belt has come off, you have bent valves. They hit the pistons if the belt has slipped more than 1 - 2 notches on the sprocket.

SP "Cozzi" skrev i melding news: snipped-for-privacy@localhost.talkaboutautos.com...

moving when the car just died. Anyway it turns out that cam belt had come off?? I need to know if this can cause any further damage to the engine i.e. valves etc. I'm taking it to a garage today and don't want to get ripped off - Any advice would be greatly appreciated.

Svend E Pettersen skrev:

Are you sure ? I thought that the 75-engine didn't suffer when/if the belt broke... A Fiat F.I.R.E engine have "plenty" of room for the valves, and they will not make contact with the pistons!

Is the 75 not a F.I.R.E engine ?????

Yes a Fire engine is a "safe" engine

firestarter skrev:

I thought so :-) But it's still a good idea to change the belt anyway every 60.000 km :-)

Yes. You are screwed, or at least in for some major costs. As you were only idling, the damage may have been minor, but you *really* want to make sure the garage removes the cylinder head and checks it over very carefully. If they don't, and something was bent (like, oh, say, a valve stem), the car may run again with a new belt, and then a couple of weeks later that valve disintegrates, spraying shrapnel all through the inside of a cylinder, damaging the piston, the cylinder walls, and everything else inside -- which means essentially you need an entire new engine, which in turn are very high costs. In my mom's Tipo, we decided to scrap after that experience rather than repair.

Jasper

Jasper Janssen skrev:

I would REALLY like you to explain, to all of us, how on earth the valves gets into contact with the pistons on a FIAT f.i.r.e. engine!

I'm conviced that it's not possible - but maybe the 75-engine is different than the other 1.2/1.2 engines ????? Please explain your statement :-)

Søren C. Fischer skrev:

^^^^^ 1.1/1.2

Really? Huh. How does Fiat arrange that while still maintaining decent compression? I've been googling for a quarter of an hour now and I can't get very good results on the FIRE stuff.

I can find references to a fiat punto 75 fire (the 1242, apparently), or to a 75sx, but not both at once. The SX is still just an option-package/class-of-luxury designator on the Punto? Then it's safe to assume it's a FIRE, though I'd personally want more confirmation than some guys in a newsgroup saying that means losing the belt is safe. There is too much potential for followon damage if it just happens to be slightly otherwise.

Jasper

Jasper Janssen skrev:

I fully understand that - my point was also to confront you with your very precise description of what happens when the belt brakes on a Fiat 1242.

We cannot assure you here - if you want to be sure, you have to visit your local Fiat garage, and ask them what happens when the cambelt brakes on a Fiat 1242 or 1108 :-)

I really haven't a clue. Sorry. I was going from the assumption that the engine was just more or less an engine, but you are (AFAICT) right that this is a FIRE engine, I just can't find any documentation on what that means (aside from being easy to assemble by robot) to the valves and pistons, so if you say FIRE engines are somehow different geometrically which results in this invulnerability, I'll just have to believe you :)

Jasper

To be honest, I got the wrong engine there. It was a 1372 I was describing, which is *not* a FIRE.

Jasper

Fully Intigrated Robotised Engine

Okay, but what does that mean to cylinder head/chamber geometry? Is there a picture anywhere?

Jasper

i read through this post and i just thought i would clear up a few things for you people. a punto 75 engine is basicly the same as a 55 but with a longer stroke and multi point injection. punto 55, 75, and 60 are all safe engines however the 16v engine aka 85 is not.

btw i have worked in a fiat dealership for 5 years, im 100% confident that anything i write is correct.

undergraduate-car-mechanic skrev:

Thank you for confirming what I wrote :-)