Cambelt lists

all 16v engines will bend, though I have seen a 16v honda engined rover not bend. early 8v vauxhalls, fiat fire engines early def ok not sure about later ones. Any more?

Celica 16v turbo engines are non interference. IOW don't bend valves if the belt breaks. Mike.

The 2.0 Ford Pinto engines (as found in early Sierra/Granada) doesn't care if the belt snaps - happened to me on the way home after I'd just bought one!

Darren

There is a directory of cambelts. Published by one of the manufacturers. Maybe a garage will let you have a look. Just can't remember the name of the producer. It lists all motors and the liklihood of engine damage as a percentage of risk. DaveK.

Everything modern bends the valves (in realistic terms) , some old stuff doesn't, but you are not really likely to buy something that old. That said , some modern designs run to 100,000 on the original belt, far longer than most vehicles actually last.

mrcheerful

In message , Dgethin writes

Gates produce a list but mainly for the US market.

It will be a very crude and inefficient engine if this is the case.

Eh? I've never scrapped a car at less than 100,000 miles - even older ones which rusted like crazy. Unless accident damaged, of course. That's only about 10 years of average use.

Non interference - what does that mean?

Mark

In message , Krycek writes

It means that the valves won't interfere (collide) with the piston crowns if the cam belt breaks.

It means the valves don't interefere with the pistons when the belt breaks.

On many engines the valves protrude into space the piston occupies when it's at the top of its stroke. When the belt breaks and the valvetrain and the crankshaft end up going at different speeds the valves get mashed by the pistons. Ugly and expensive.

On some older designs of engine its possible for the valves to be at their full extension and the piston to be at the top of the cylinder without them coming into contact with each other. This is non-interference. Hurrah!

HTH

Douglas

I know we don't, we are not average, but look at the reg numbers of the cars scurrying about, very little pre p reg.

mrcheerful

Probably easier to do with forced induction given the lower CR. Might also be that cut outs in the pistons etc don't upset combustion so much given that the mixture is pushed in.

The message from "Darren Jarvis" contains these words:

Austin-Rover S-series 1.6 engines don't mind, in my experience.

The message from "mrcheerful ." contains these words:

Oi - I just bought a car with 220,000 miles on it and it's going strong. But then again it's had its belt change three or four times.

cambelt. I know there are some cars which can get away with a broken belt. >

It will be a very crude and inefficient engine if this is the case.

Ain't necessarily so according to the list Scooby Impreza and Legacy seem to be ok .I find it a little odd the Toyota range are mostly interference but Lexus are mostly not like the song says "it makes me wonder" Derek

I should have excluded low compression pressure fed engines.

Do Toyota still use belts? Another reason to avoid them, then.

are you sure this is the only reason behind interference designs? allow me to reiterate:

many times its up to the ethics of the engineering team designing the engine .

assuming that timing chains are no longer in fashion: a)they can decide to make an interference engine where valves/pistons will collide if the belt snaps.this will give them more freedom in shaping the chamber for (marginally??) better fuel combustion->more power and fuel economy

b)or they can decide to make a non interference engine where the piston

has depressions in it so that a valve will never impact on it. this engine will be more forgiving on people who race/neglect/ forget/cant afford/ dont know they need to change the belt.

now since

-a timing belt will last the warranty period (at least for normal use of car)

-that the longer the average car lasts the less cars will be sold in the future

-manufacturers are less interested in consumers who cant afford to change the belt at recommended intervals

which way do you think the engineering team will go? i wonder why anyone goes for b) today. (i think it might have to do with submitting cars for rally competitions where you dont want to retire a car just for a belt snap.)

In news:Zjmge.29770$ snipped-for-privacy@text.news.blueyonder.co.uk, mrcheerful . decided to enlighten our sheltered souls with a rant as follows

Oooh, that's just cheered me up.

In the fleet of stuff I drive there's a '73 M reg Jensen, '84 A reg 911, 89 F reg Merc, '89 F reg Golf, '86 D reg Capri, '90 H reg XJ-S.

The Jensen is the lowest mileage - 16,900, then it's the Capri - 83,000, the Porsche - 93,000, the Golf - 115,600, the Merc - 166,000, and the XJ-S odo stopped working sometime in the middle ages.

Just to back up the 100,000 mile theory, the Jensen and Capri are both off the road at the moment with unfortunate mechanical problems.