Safe engines

ihateclowns11

Hi folks, I was just wondering if anybody out there knows about 8 valve safe engines. I used to own an 8 valve fiat punto and when I was going to change the timing belt on it a mechanic told me not to worry bout it because if it snapped no damage would be done. Well now I have a new car ( van ) . Its an 04 nissan kubistar 1.5 dci 60 diesel engine. I think it only has 8 valves and if it does does this mean its a safe engine too? . So if the belt snapped it would be alright? .

Henry Ford III

You are looking for "non interference" engines.

George Dalton

No you wouldn't be alright, the 1.5DCI is an interference engine.

There are very very few non-interference engines, the vast majority of engines are interference engines so will do a lot of damage if the timing belt breaks.

ihateclowns11

Ahh ok thx for the help folks

Chimaera

It's also time to find a new mechanic: any mechanic who thinks it's ok to ignore the maintenance schedule for any car is one to be avoided.

mickdw

Chimaera wrote: »

It's also time to find a new mechanic: any mechanic who thinks it's ok to ignore the maintenance schedule for any car is one to be avoided.

If it was a clapped out old punto, he was probably doing them a favour tbh.
There are some in the trade would would take it in, charge for new belt and not bother given that If it broke, they would get away with it by replacing the belt then.

JohnBoy26

Chimaera wrote: »

It's also time to find a new mechanic: any mechanic who thinks it's ok to ignore the maintenance schedule for any car is one to be avoided.

Get off your high horse. The "time to find a new mechanic" response is getting tiresome at this stage. You shouldn't post a response like that without knowing the full story and unless you were there in person I fail to see how you have tbh. You could be losing this mechanic a customer and giving them an undeserved reputation for all you know.

quadrifoglio verde

Chimaera wrote: »

It's also time to find a new mechanic: any mechanic who thinks it's ok to ignore the maintenance schedule for any car is one to be avoided.

Meh I know of a mechanic in the uk who ran his 156 ts to 109k miles and 9 years. Granted it was an experiment to see how long it'd actually last, but the cost to rebuild the engine worked out cheaper than doing the belts. And he got to have fun with the engine rebuild as well!:)

To be honest if I had a non interference engine I wouldn't change the belts either. Unless it was looking like a raggedy old yoke

Chimaera

JohnBoy26 wrote: »

Get off your high horse. The "time to find a new mechanic" response is getting tiresome at this stage. You shouldn't post a response like that without knowing the full story and unless you were there in person I fail to see how you have tbh. You could be losing this mechanic a customer and giving them an undeserved reputation for all you know.

How is expecting a professional to work to the manufacturer's specification being on a high horse exactly? Most people depend on their mechanic to advise them in these matters, and any advice like this is asking for trouble for all involved.

Chimaera

It's also worth bearing in mind that even non-interference engines are not immune to valve damage from a broken belt, just less vulnerable to it.

Guy:Incognito

Whats the mechanic that advises you to leave it till it goes going to do to sort you out when the belt decides to snap on a Sunday evening when your at the far end of the country? Will he be rushing down to help you?

Seweryn

ihateclowns11 wrote: »

Hi folks, I was just wondering if anybody out there knows about 8 valve safe engines.

Not necessarily an 8-valve engines, but most of Subaru engines up to 2.2 l and manufactured by 1996 are non-interference.

Popoutman

JohnBoy26 wrote: »

Get off your high horse. The "time to find a new mechanic" response is getting tiresome at this stage. You shouldn't post a response like that without knowing the full story and unless you were there in person I fail to see how you have tbh. You could be losing this mechanic a customer and giving them an undeserved reputation for all you know.

Any mechanic that does not follow the manufacturer's service schedule is a moron and should be well avoided, and that information should be put out there to protect people from idiots like that. Do you honestly think that a shade-tree mechanic knows better about a service schedule than the engineers that actually designed and built the car? No? didn't think so. There's a good reason that the warranty is based on the timely replacement of certain parts and the examination of others.
Any mechanic that purposefully avoids the service schedule for a car is not fit to work on cars, and I would shout that fact from the rooftops. Its a reputation that is fully deserved it seems..

There is a very good reason why warranties are voided on cars when the service intervals get ignored. I've over 325,000 km on my car and I'm still following the service interval recommendations...

JohnBoy26

Popoutman wrote: »

Any mechanic that does not follow the manufacturer's service schedule is a moron and should be well avoided, and that information should be put out there to protect people from idiots like that. Do you honestly think that a shade-tree mechanic knows better about a service schedule than the engineers that actually designed and built the car? No? didn't think so. There's a good reason that the warranty is based on the timely replacement of certain parts and the examination of others.
Any mechanic that purposefully avoids the service schedule for a car is not fit to work on cars, and I would shout that fact from the rooftops. Its a reputation that is fully deserved it seems..

There is a very good reason why warranties are voided on cars when the service intervals get ignored. I've over 325,000 km on my car and I'm still following the service interval recommendations...

Another high horse that doesn't know what they are talking about. There is a difference between what's done in theory and situations in reality.

If the op's car was an old banger on it's last legs it might not of been worth doing the belt as the one that's in it could out live the car, as another poster said the mech could of just been just doing the op a favor, who knows.

Nobody knows what the story is so it's a bit rich for you and some other posters to castigate this mechanic as it may be undeserved, that is unless you know this person and was there at the time as a witness? No? There are two sides to every story, don't judge someone based on one side.

Calling someone a "shade-tree mechanic" "moron" and "idiot" without knowing the person or their qualifications is also unfounded, unwarranted and horrible imo.

I obviously agree that under normal circumstances service schedules should be followed but for all you know this mechanic could be following manufacturers guidlines under these normal circumstances.

And the "engineers" that designed and built the car don't always get things right so I wouldn't take a manufacturers schedule as gospel, your point about the "engineers" that built the car knowing better about service schedules than mechanics doesn't always ring true. A mechanic's experience sometimes works better.

pablo128

ihateclowns11 wrote: »

Hi folks, I was just wondering if anybody out there knows about 8 valve safe engines. I used to own an 8 valve fiat punto and when I was going to change the timing belt on it a mechanic told me not to worry bout it because if it snapped no damage would be done. Well now I have a new car ( van ) . Its an 04 nissan kubistar 1.5 dci 60 diesel engine. I think it only has 8 valves and if it does does this mean its a safe engine too? . So if the belt snapped it would be alright? .

The Fiat/Alfa/Opel 1.9 and 2.4 diesel engines tend to break rockers when the belt breaks. Probably as expensive to repair, but a far easier job as the head doesn't have to come off.
The old Isuzu 1.7 diesel engine in the Opels used to be the same. Given that the newer Opels use a newer version of the same engine, they are likely the same when/if the belt breaks.

CJhaughey

Broken timing belts can cause others issues aside from valve/piston contact.
Loose ends of the belt can catch pulleys and bend things.
Not all timing belts break, on some engines the tensioner gives up long before the belt.

hi5

My Mazda MX5 1.6 had a non interference engine, brought a certain peace of mind:)

Toyotafanboi

it's all well and good saying don't change it on a non interference engine, but imo i can't see a single logical case for it. specially on an 8v punto where a belt change takes less than an hour.

what are you saving by doing (or not doing) so? time? money?

i'd be fairly disappointed if the belt broke on a wet winters night somewhere, or on the morning of a job interview etc. you can never really trust the car and if/ when it does break all your time and financial savings are very much undone.

i once played timing bely roulette with my diesel focus, it had no timing belt or service history with it but i took it from 150 to 170k miles and i couldn't trust that car for one minute of it. never again.

EazyD

If a belt is due to be done on a car that's used regularly, there really is no excuse not to do it, non-interference or not.

JohnBoy26

Obviously if you depend on your car a lot it would be much better to do the belt, as toyotafanboi says you will always be worried when playing roulette and the car could leave you down at the wrong time. I don't believe in playing roulette myself and I would never encourage it but I can see the otherside of the argument too.

Some posters are jumping the gun a little too quickly with the "time to find a new mechanic" argument is the point I'm trying to make.

For all we know the op could of just asked the mechanic if the engine would be damaged if the belt broke and the mechanic quiet rightly (in this situation) said no. That's the exact question that the op put to the people of boards about their new car"so if the belt snapped would it be alrite?" And who's to say that the mechanic didn't warn the op that if the belt breaks that they would be left stranded.

Nobody knows the full story yet some on here (who think they know it all) are blackening this mechanics rep without knowing the full facts. This kind of stuff seems to have become a trend of boards in recent years.

rex-x

This thread highlights everything that is wrong with this forum and why it is not more widely used

Dartz

If you're really worried about cambelts and valve impacts, but a Mazda rotary!

Popoutman

rex-x wrote: »

This thread highlights everything that is wrong with this forum and why it is not more widely used

Agreed. People giving correct and safe advice being chastised by the clueless for exactly that - while those clueless are giving incorrect and unsafe advice themselves. It's a pity as there are some genuine queries that can be well answered by the really knowledgeable people that use this forum, only to have teh signal drowned out by idiots with nothing but noise to add to the threads.

Popoutman

My comments about idiotic shade-tree mechanics that choose to not follow the manufacturer's schedules still stand - as the schedules are there for a reason. No mechanic worth their salt would change away from the schedules. Certainly not to extend unnecessarily for items that are required to change at a certain mileage multiple. Inspection items should be changed when appropriate for sure and that doesn't mean every interval but those items that are specified to change *must be* changed as instructed.

As for this point of view being a "high horse"? It's the simple objective truth, and there's no denying that no matter how much noise you make or hands being waved at it. It's simple. No mechanic should deviate from the manufacturer guidelines. The designers in the overwhelming majority of cases *do* know a lot more than the backyard mechanics about the products they have designed and built.

Note that I wasn't speaking about the specific case here that the below poster assumed I was referencing, but the general case, lest the comprehension issue shown in the below answer be propagated onwards.

JohnBoy26 wrote: »

Another high horse that doesn't know what they are talking about. There is a difference between what's done in theory and situations in reality.

If the op's car was an old banger on it's last legs it might not of been worth doing the belt as the one that's in it could out live the car, as another poster said the mech could of just been just doing the op a favor, who knows.

Nobody knows what the story is so it's a bit rich for you and some other posters to castigate this mechanic as it may be undeserved, that is unless you know this person and was there at the time as a witness? No? There are two sides to every story, don't judge someone based on one side.

Calling someone a "shade-tree mechanic" "moron" and "idiot" without knowing the person or their qualifications is also unfounded, unwarranted and horrible imo.

I obviously agree that under normal circumstances service schedules should be followed but for all you know this mechanic could be following manufacturers guidlines under these normal circumstances.

And the "engineers" that designed and built the car don't always get things right so I wouldn't take a manufacturers schedule as gospel, your point about the "engineers" that built the car knowing better about service schedules than mechanics doesn't always ring true. A mechanic's experience sometimes works better.

landmarkjohn

I ran my Mazda Xedos 9 (2.5 V6 non interference) to 137,000 miles on the original timing belt. Changed it then mainly because the tensioner was getting noisy. Not sure why I let it go so long, probably because it was an expensive job (€400) and I guess there was some comfort that it was non interference.

But I would be religious on changing the oil and filter every 10,000 miles with Mobil 1 no less!

I knew from the forums for that particular car that timing belt breaking was rare enough, I think some engines a "harder" on the belt and more prone to breaking if recommended intervals are not strictly adhered to (Fiats and Alfas come to mind). Mazda running well with 155,000 :-)

Mycroft H

Timing chains win. Except in BMW's case.

Popoutman

Popoutman wrote: »

My comments about idiotic shade-tree mechanics that choose to not follow the manufacturer's schedules still stand

Especially with old cars not worth much people want the option of the cheap fix etc. It's most likely the op was just given the option by the mechanic that if you want to save a few bob then you could chance leaving the belt.

When I was running a car not worth much my mechanic always offered a cheap quick fix option for bits that went wrong rather than the full expensive option (then left me to decide which route). It saved me a lot of money as any of the quick fixes out lived my time owning the car.

Leonard Hofstadter

JohnBoy26 wrote: »

Another high horse that doesn't know what they are talking about. There is a difference between what's done in theory and situations in reality.

If the op's car was an old banger on it's last legs it might not of been worth doing the belt as the one that's in it could out live the car, as another poster said the mech could of just been just doing the op a favor, who knows.

Nobody knows what the story is so it's a bit rich for you and some other posters to castigate this mechanic as it may be undeserved, that is unless you know this person and was there at the time as a witness? No? There are two sides to every story, don't judge someone based on one side.

Calling someone a "shade-tree mechanic" "moron" and "idiot" without knowing the person or their qualifications is also unfounded, unwarranted and horrible imo.

I obviously agree that under normal circumstances service schedules should be followed but for all you know this mechanic could be following manufacturers guidlines under these normal circumstances.

I couldn't agree more. Under normal circumstances, a mechanic should be shot for not advising the owner to adhere to the manufacturer's service schedule. Though in the case of a lot of modern cars with their 30k+ service intervals, following the manufacturer's recommendations is the bare minimum that should be done and really all cars should be serviced at least once a year or every 20k km (regardless of what the manufacturer says), long life servicing and oil or not.

However, common sense must also come into play, if for example it's a 13 year old car (or even older) and needs a lot of work to get it through the NCT in say 5-6 months time, but is due a timing belt change right now then it obviously makes perfect sense that a mechanic would say it's ok to leave it and play Russian roulette with it, especially if the owner was thinking of scrapping it anyway but doesn't have the funds to change the car right now (especially on a non-interference engine). Hardly worth doing a timing belt in such circumstances.