Hi chaps anyone had or know to the damage posibility if timing belt breaks when the engine is running, albeit at idle? is it worth a new belt to see or has the grim reaper dealt his death wish?

 

Incidently this is a customer`s car and it may be covered by warranty as the dealer put in writing the belt had been changed, having partially stripped the front it is well clear this belt is the original!

Warning to all, change them belts unless you are 100% sure of it.

 

Jeff TT

 

Ps How can you be 100% sure of your belt??

change it that`s how.

Hi Jeff - knew I'd seen it somewhere... pics & everything!

http://zclub.org.nz/shared/technical/break_cambelt.htm

 

Cheers - Gio

Hi Jeff!!

 

I was speaking to a mate of mine (ex BTCC) who does a small amount of mechanical work for me from time to time. I had him time-up my Z engine when I rebuilt it. I asked him the same question, and he said to try a new belt on first. Theoretically all the valves should be in the correct sequence, so no piston/valve contact. What he did say though, was what possibly happens sometimes is the valves 'tangle' themselves i.e. both inlet and exhaust are fully open, then as they both close, the heads clash and bend the stems. Best of luck to you Jeff, but one last thing, if you 'mess' with this car, will this invalidate his warranty???

 

Regards

 

Robert.

 

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[This message has been edited by dunk300zxtt (edited 22-04-2002).]

VG30DE(TT) engine is an interference design, which means if the belt is put on incorrectly or if it snaps you WILL always have valves contacting pistons. (even at low rpms) = internal engine damage

 

-Eric

 

 

Originally posted by lymon:

VG30DE(TT) engine is an interference design, which means if the belt is put on incorrectly or if it snaps you WILL always have valves contacting pistons. (even at low rpms) = internal engine damage

 

-Eric

 

 

My old Rover 216 GTi had an interference engine too. My water pump seized one morning at full throttle and about 5k revs and that pulled the timing belt off (I'd had the belt changed about 7k before that too, but no-one mentioned the water pump ). The mechanics were amazed to find that everything was within tolerance when they took it apart and no damage was done.

 

Not sure how similar the 2 designs are, but just because it's an interference engine doesn't necessarily mean that damage will have occurred.

 

 

[This message has been edited by Dave Marley (edited 23-04-2002).]

Hi robert,

 

What was the purpose of your rebuild, was it due to a broken cambelt and if so were you lucky enough to escape without any inernal damage.

 

I only ask because it's my car that jeff is talking about.

 

Regards,

 

Dean

 

 

 

Hi Dean!

 

I pulled my engine apart just after I bought the car because I bought it stolen/recovered with a thrashed/blown-up engine. Scrap crank & no.6 con-rod & piston. I can't help with broken cam-belts, because I haven't had any more experience with Z engines. I doubt very much the Z engine is 'safe' but even so, you might be lucky. Stick a belt on and do a compression test. This may show up a bent valve (or half a dozen (sorry )). Then make a decision after that. The removal/dissasembly of a Z engine is not an easy task.

 

Many regards, and hope this helps

 

Robert.

 

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Originally posted by Jeff TT:

Hi chaps anyone had or know to the damage posibility if timing belt breaks when the engine is running, albeit at idle? is it worth a new belt to see or has the grim reaper dealt his death wish?

 

Incidently this is a customer`s car and it may be covered by warranty as the dealer put in writing the belt had been changed, having partially stripped the front it is well clear this belt is the original!

Warning to all, change them belts unless you are 100% sure of it.

 

Jeff TT

 

Ps How can you be 100% sure of your belt??

change it that`s how.

 

Jeff....Do you work on Z31s as well? I sold my Z32 NA and have recently aquired a 300ZX Z31 Turbo, which hasn't had a cambelt change and is on about 78K miles.

There's a lot more under-bonnet access at the front of the engine too!