Interference engines

"Craig" > wrote in message
...
> The older 1.8s are non-interferance. You can break belts all day long at
> redline & they wouldn't care. The newer ones AEG & newer technically
> aren't but they are extremely close & I have seen them hit due to carbon
> buildup on the pistons.
>
> Craig
>
> "Bill Leary" > wrote in message
> ...
>> "Craig" > wrote in message
>> ...
>>>I call really lucky twice.
>>
>> I was running around 4,000 RPM about 30 seconds before this too.
>>
>>> Don't forget at higher RPMs you are usually accelerating in gear. This
>>> gives the rotating mass in the engine more momentum which allows it to
>>> continue rotating after it dies. Also the force of being in gear will
>>> force the pistons around for another HIT.
>>
>> I'd figured on momentum, but didn't think the cam shafts would really
>> have
>> enough to keep it spinning. On the other hand, as you mention, at high
>> RPM
>> there's a lot of rotational energy stored in there.
>>
>> Someone mentioned that, if it's going slow enough, there's a "snap back"
>> from the valve springs which would tend to take the valves to one of the
>> safe positions.
>>
>>> I have seen 1.8T motors survive broken timing belts while at idle &
>>> those
>>> are most definatly interferance engines.
>>
>> Related question: Are the 8V (as in 1990 Corrado, 1980's Sciroccos and
>> Rabbits) also interference types?
>>
>> - Bill
>>
>Youre lucky.

usually, unless the owner is at or near the upper RPM range, then things go
bad real fast!



"> AFAIK If they are 8v, they are not usually an interference
> engine.........unless they are diesel engines which are interference.
>

Thanks all for your comments and observations.

I'll look into the age thing.

And that caused me to wonder something else. The car has fairly low
mileage. Depending on how much faith I put in the odometer, between 120 and
140K. But it spent several years sitting in a garage. I'm wondering if
sitting there, not moving, for all those years might not have also aged the
belt and contributed to this failure.

- Bill

Absolutely. Age is just as big a factor for belts as mileage.


"Bill Leary" > wrote in message
...
> Thanks all for your comments and observations.
>
> I'll look into the age thing.
>
> And that caused me to wonder something else. The car has fairly low
> mileage. Depending on how much faith I put in the odometer, between 120
> and
> 140K. But it spent several years sitting in a garage. I'm wondering if
> sitting there, not moving, for all those years might not have also aged
> the
> belt and contributed to this failure.
>
> - Bill
>