Non Interference Motor??

Pro5driver

Member
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2002 Mazda Protege 5
I was told that I have this type of motor and that if the timing belt goes everything will not go bad like in other motors? Is this true or a myth?
 
to the best of my knowledge, this is a non interference motor.

although replace your timing belt at the intervals and youll be fine.
 
FSDE is non-interference so if timing goes off you won't destroy your valves. This does not mean you won't cause other damage however...
 
FSDE is non-interference so if timing goes off you won't destroy your valves. This does not mean you won't cause other damage however...

I'm curious what other damage you're referring to. I can't think of anything else that could be damaged by just a broken timing belt.
 
I'm curious what other damage you're referring to. I can't think of anything else that could be damaged by just a broken timing belt.
Let the belt break and find out. The point here is you really don't want to find out so it would be in your best interest to change the timing belt at 60,000 intervals. While you're at it might as well change the water pump and other drive belts. Preventive maintenance is the key.
 
Our engines can go up 100k miles before doing the belt change. But good preventive is always wise.
 

I'm so tired of this being spread around(I'm not trying to single you out tsunami, I'm talking to everyone who reads this.) If you only read that this was an interference motor from somewhere else, don't spread the "myth" that it is. I have spoken with several mazda techs about this, as well as Mazda corporate, and have been assured that it is a NON-INTERFERENCE motor.

FSDE is non-interference so if timing goes off you won't destroy your valves. This does not mean you won't cause other damage however...

Yes, if your timing belt breaks while you are on a mountain road, you may freak out and drive off a cliff :). But otherwise, you're not going to do any other damage :bs:

Let the belt break and find out. The point here is you really don't want to find out so it would be in your best interest to change the timing belt at 60,000 intervals. While you're at it might as well change the water pump and other drive belts. Preventive maintenance is the key.

Don't try to freak him out by imagining what damage could occur if his belt breaks, unless you know first-hand. In 99 cases out of 100, the only thing that will happen is your car will stop running, and you will have to take it to a shop to get the belt replaced, and have your valves re-timed.

Our engines can go up 100k miles before doing the belt change. But good preventive is always wise.

Agreed. Unless you live in an extremely cold climate, you can wait until 105k miles to change the belt (that is what is listed in my manual). I realize other manuals may say 60K, but again, unless it's very cold year round, you will be fine.
 
I'm curious what other damage you're referring to. I can't think of anything else that could be damaged by just a broken timing belt.
While no physical damage will occur directly you run all sorts of risks when running with severely screwed up timing. Chances are the belt just won't snap but it will stretch or tear. This will through off your timing, which could lead to detonation issues and those are never good.
 
I bought my belt a long time ago and was going to see how long the original belt would go bofore it broke and prove that there was no damage. Well, I got tired of waiting and changed it at 156,000 miles.
 
Let the belt break and find out. The point here is you really don't want to find out so it would be in your best interest to change the timing belt at 60,000 intervals. While you're at it might as well change the water pump and other drive belts. Preventive maintenance is the key.

In fact, I know that nothing in the engine will be damaged by this, but was curious to hear the response. If the P5 were my daily driver, I would be inclined to let the timing belt go until it breaks. But it's my wife's car, and she uses it for some work occasions when she can't afford the breakdown. Her car is at about 107,000 miles (service interval is 105,000), and I'll be changing the belt when it gets a little warmer outside. My point is that telling people that a broken timing will cause some sort of collateral damage is just silly.
 
In fact, I know that nothing in the engine will be damaged by this, but was curious to hear the response. If the P5 were my daily driver, I would be inclined to let the timing belt go until it breaks. But it's my wife's car, and she uses it for some work occasions when she can't afford the breakdown. Her car is at about 107,000 miles (service interval is 105,000), and I'll be changing the belt when it gets a little warmer outside. My point is that telling people that a broken timing will cause some sort of collateral damage is just silly.
Even if a broken timing belt doesn't do any damage to your engine doesn't mean you should run it unit it breaks because you just don't know when and where that will happen. If you're lucky it will break on a clear sunny day just as you're pulling into a repare shop or a garage just to ask a simple question or it can break in the middle of winter, at night, with 3 inches of snow on the ground or in a down pour and you're miles away from home with a loaded car. Then you'll have to call a tow truck, find a repare shop near where ever you might be at the time, find a way to get home with all your stuff, and find alternate form of transportation while it is being fixed. My point is its not just getting stuck when the belt breaks but all the problems and logistics involved in getting it to a shop and getting it fixed.
 
Even if a broken timing belt doesn't do any damage to your engine doesn't mean you should run it unit it breaks because you just don't know when and where that will happen. If you're lucky it will break on a clear sunny day just as you're pulling into a repare shop or a garage just to ask a simple question or it can break in the middle of winter, at night, with 3 inches of snow on the ground or in a down pour and you're miles away from home with a loaded car. Then you'll have to call a tow truck, find a repare shop near where ever you might be at the time, find a way to get home with all your stuff, and find alternate form of transportation while it is being fixed. My point is its not just getting stuck when the belt breaks but all the problems and logistics involved in getting it to a shop and getting it fixed.

The point is that no actual damage will come to the car as a result of the broken belt. Obviously a broken belt will cause some sort of inconvenience, but I honestly wouldn't be too bothered by towing a car home and just throwing a new timing belt on. I wouldn't go on a road-trip in those circumstances though. That's just pressing your luck.
 
The point is that no actual damage will come to the car as a result of the broken belt. Obviously a broken belt will cause some sort of inconvenience, but I honestly wouldn't be too bothered by towing a car home and just throwing a new timing belt on. I wouldn't go on a road-trip in those circumstances though. That's just pressing your luck.
Basically that is my point. Why limit yourself to where you can go? Why not just get it changed and be free to drive where ever and when ever?
 
Basically that is my point. Why limit yourself to where you can go? Why not just get it changed and be free to drive where ever and when ever?

I think you are agreeing with me then. That's why I'm not waiting. The idea is that if the limitation on where you can drive is a non-issue, then a broken belt is a non-issue. I honestly take my GTI most places just because it's faster and more fun to drive, although the P5 does handle a little better and beats it in mileage.
 
Thanks for the answer guys. I will be changing the belt next month cause I have no idea if it has ever been changed.
 
I'm so tired of this being spread around(I'm not trying to single you out tsunami, I'm talking to everyone who reads this.) If you only read that this was an interference motor from somewhere else, don't spread the "myth" that it is. I have spoken with several mazda techs about this, as well as Mazda corporate, and have been assured that it is a NON-INTERFERENCE motor.

OOps. I read the post wrong, I was saying it was a myth that the car had a interference motor, LOL. Curse my poor reading skills.
 
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OOps. I read the post wrong, I was saying it was a myth that the car had a non interference motor, LOL. Curse my poor reading skills.

And still wrong. It is not a myth that this is a non-interference motor. It is in fact a non-interference motor.
 
The "myth" part is that for some mythological reason people won't believe that it is in fact non-interference & these well maybe it is or maybe it's not threads keep going on forever. See previous 5000 int/non-int threads..............If s*** don't hit, you must quit, believing the bulls***
 
The "myth" part is that for some mythological reason people won't believe that it is in fact non-interference & these well maybe it is or maybe it's not threads keep going on forever. See previous 5000 int/non-int threads..............If s*** don't hit, you must quit, believing the bulls***

This. ^

It's not hard to do the timing belt install yourself, either. Grab the service manual and read it. Really really easy to do if you have a bunch of hours. It can all be done with hand tools, too.
 
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