Hi Everyone,

I'm new to the forum and I joined specifically to ask the question below.

A friend of mine's Fiat Punto 1.4 with the T-Jet engine broke down (cambelt broke). Year model is 2010.

I would like to know if that is an "interfering" engine or not, so that we know if the valves could be bent or pistons broken.

We travelled 300km to his Granny's funeral but have to return home without his car. So the reason I need to know this is that a mechanic can tell us anything over the phone, ie: You have to get a new head or new valves / pistons etc.

It would be greatly appreciated if anyone can give us some information on the above engine.

Thank you,

Carel

Does the cambelt broke while your driving. Can u turn the engine by hand now. If it's is happend while you driving. Most likely your valves are gone and your pistons to. Big expensive job to repair it. Better look for a donor engine in that matter.

I think it's not a free running engine where the valves never touch any piston when the belt brake. Good luck with the repair.

only the older 8Valve engines are "safe",

parts, normally it's a seized idler that takes the belt with it,

minimum of cambelt kit, water pump, head gasket, and 2 x valves

worth removing head and looking, but prepare for bad news,

Charlie

Brutusnl: Yes it broke while driving. The starter still turn the engine.

Varesecrazy: How do I know if it is the 8 valve engine, and what has the water pump got to do with it?

Thanks for your quick responses.

carelvos said:

Brutusnl: Yes it broke while driving. The starter still turn the engine.

Varesecrazy: How do I know if it is the 8 valve engine, and what has the water pump got to do with it?

Thanks for your quick responses.

Click to expand...

as stated, cambelts rarely fail..,

it'll be something that the cambelt drives has seized - wearing out the belt

waterpump is driven by the cambelt,so is the idler bearing,

for an hours labour it's worth removing the head for inspection..,

as a 2010 car still has a value

charlie

Are we sure T-JET 16v engine (NOT NA 16v ''starjet'') is not a safe engine ?

cmosfxx said:

Are we sure T-JET 16v engine (NOT NA 16v ''starjet'') is not a safe engine ?

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It's essentially the same engine. I'd expect damage. Non interference engines are a rarity nowadays.

Starjet has nothing in common with T-jet engine...

cmosfxx said:

Starjet has nothing in common with T-jet engine...

Click to expand...

they are both 16v super fire engines, both will suffer damage if cam belt goes, no ifs no buts

okie dokie lol

Bad for OP though :/

Yes the valves interfere with the piston crown causing catastrophic engine damage usually ending up with hundreds of pounds worth of damage ? which reminds me my belt is due for changing

cmosfxx said:

Starjet has nothing in common with T-jet engine...

Click to expand...

T Jet was developed from 1.4 16v SuperFIRE lump. Almost every component differs in detail, but only in detail.

I would add that depending on the camshaft and follower design even if there it is an interference design then there may be no valve damage at all. However there will be rocker arm damage and these are easier to replace than removing head and valves.

To clarify. The 1.9 16V MJET diesel engine is overhead cam acting on rocker arms that then depress the valves. These rocker arms have inbuilt weak/fracture points which are designed to break and release the valve when a valve head hits a piston head. In addtion the valves vertically aligned with piston head/stoke and not inclined at an angle so the strike force is not at an angle but vertically up the valve stem. (Imagine a hammer and drift setup).

Any interference engine design that uses the typical Fiat/Lampredi overhead camshaft with vertically in-line followers will suffer bad valve, guide and possibly piston damage. Also depending on rmp when contact is made and if the valve stem/head break away from each other then even more damage can be done to block/bores.

I don't know what other engines in the fiat range use the overhead cam with rocker arm followers? Possibly the 8V MJET, 1.6 16V MJET? ? ?