355 Cam belt advice needed

Now including bearings so that you have a baseline for your ownership

Or spend the next few days reading all the hundreds of previous similar threads before coming to the same conclusion !!

 

probably waste of money to do them now....you can go on TR and 355 boards and in reality very few owners have had a belt go. have someone you trust look at it. or if you want zero risk just go ahead and do it. i have 2k miles on a 10 yr old bet that im doing now. the belt looks brand new.

that being said my cars are stored in climate controlled facilities and never exposed to the elements.

 

Oh boy.

It' like changing your underwear. It depends on how often you **** yourself.

Seriously, belts on my 308, which I bought new in 85, have been changed once. Belts on my 355 which I bought in 2013 were changed at 7, 4 and 7 years, and are currently 7 years,10k miles old.

It comes down to what are you comfortable with.

 

yeh i was debating just saying yes def do them now or the world will end just to avoid this thread taking on a life of its own.
there is no right answer.

 

I actually know of a one owner F355 in the Midwest that has never had its timing belts changed from day one, it has not been a garage queen and it is still running just fine. Obviously I would never recommend this interval on any engine with cam belts much less a Ferrari but it does show how durable modern timing belts can be.

In my opinion, for what it's worth, if your belts and tensioner bearings pass an inspection you should be good for at least another two years.

 

And how would you inspect the belts and tensioner bearings with the engine in the car? If you remove the engine from the car to get the inspection done, why would you put the old belts and bearings back?

 

I wouldn't remove the engine to inspect them. I can see enough of my belts with the engine in the car, the belt covers on and the car on a lift to tell if they are worn, cracked or damaged. I haven't tried to take off my belt covers yet with the engine in place but it looks doable to get a look at the tensioners and the belt tension. I could be totally off base with the ability to do a complete inspection with the engine in place but even if it isn't possible I still see no reason his belts would need replacement immediately.

 

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No you cannot remove the black timing belt covers with the engine in the car. There are a couple of long m6 bolts buried deep in the belly of the beast. I am in the middle of my 348 engine out right now, and once again it proves that it is not the timing belts that are problematic. It's everything else that you get to look at once the engine is out of the car.

But, it's his car, his money, his decision. Go to it.

 

Good to know that those belt covers can only be removed with the engine out. Thanks for clarifying.
I think you hit the nail on the head when it comes to the full service too. It’s generally not the belts that are the problem rather a lot of the rest of the parts that need to be replaced at the same time and the only way to do those is with the engine out.

 

My experience is On my 355 is the same as Mitchell said.
This last 1 for me had a leaky water pump as it was original and about 16 years old, also had a very slight oil leak from a cam seal, and many other small things that are way easier to do when the engine is out.
That being said if engine is clean and no oil leaks I would likely drive it for a summer or a few thousand miles.
You will likely be surprised on the few things you can clean up and fix while it’s out.

 

I'd like to know what you are going to inspect them for? Aging of the belts isn't visually detectable.

 

Tire manufacturers give a usable lifespan of their tires of around 5 or 6 years and it doesn't matter if it has been driven of not. Timing belts are very similar. Why would they be any different?

 

What kind of inspection? What would I look for? Goodyear says their tires are good for 5 years. I was once driving a Testarossa with original tires and very few miles but were 15 years old. They passed inspection too. They looked perfect. Something happened while driving and I had to hit the brakes pretty good. They locked up with no provocation and that car skidded a very long way. The rubber in the tires was rock hard and provided very little stopping power. But they looked good.

Inspecting belts by eye. What a joke.

 

You can actually see quite a bit by looking at used timing belts. If the teeth are developing cracks around their bases you know the belt will be failing soon. If the edges are worn or frayed you know the belt is not running true and there is an alignment problem. If the smooth side of the belt is worn shiny it may be hardened or the tension is off. If a belt is wet with oil and contaminated you know the belt is compromised, needs to be replaced and the leak needs to be repaired. A careful listen with a mechanics stethoscope around a tensioner bearing while the engine is running can alert you if it is failing. Is this a perfect way to tell how good a belt or tensioner is? No, but if you do notice any of these things you can at least make the decision to stop driving the car and have the belts serviced right away.
Again, back to the topic of this thread, I don’t see how a visual inspection of the belts on this engine would hurt and only help if something doesn’t look right. With his description of only light use since the last major I see no reason to change the belts for at least another two years as long as everything looks fine.

 

In addition to Dan's comments:

Visual inspection of a belt fatigue test run to failure. A = new. b,c,d at equal time intervals. e at failure.This is for a belt running correctly on the pulleys.

You seldom see a belt from a Ferrari that even looks like b.

Most of the damage to the belt is the result of stretch over time which result in a change in the tooth pitch therefore the belt doesn't mesh correctly with the pulleys. That stretch is the result of fatigue and, as seen in b, is visually apparent long before the fatigue life is reached and the belt fails.


Another figure from a 308 thread showing the kind of damage a belt can withstand (reportedly a stone got caught in the belt) without catastrophic failure.

 

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This is one of 24 valves that look like this following a right bank tensioner bearing failure on my 1999 550 Maranello. It occurred in 2003 to the previous owner with original belts and bearings which were less than five years old and at ~29,000 miles. At the time, the car was still within Factory recommendations for a major service.

 

Ugg

 

As you note, Barry, the car was within the factory recommendations for service. But **** happens. Things even fail during the warranty period.

Where do yo set the limits?

You make your choices and accept the responsibility.

 

And some time doing a major IS the problem.

Cam phase sensor malfunction

 

And my dentist has related to me the problems he sees from improper brushing. So in your world we are better off not doing it.

 

So I guess only belts that look like they are circling the drain are the only ones that are going to fail.

Pretty stupid position.

 

John, it's true that the 550 was within the Factory recommendation for a major service. The car was indeed scheduled for its major service but the previous owner tracked the car frequently. The incident occurred two weeks prior to its scheduled major as he was leaving Pocono Raceway for his trip home. He was stopped at a traffic light and as he moved off after the light turned green, he heard the noise and shut the engine down.

Where do I set the limits? I feel the Factory recommendation is a good place to start. If the car is tracked, more frequent belt and tensioner changes are indicated. I did so every three years when I tracked my 550. The 550 is now retired from track duty and I regularly track my F355 Challenge. The Challenge car gets serviced and track-prepped frequently with each track event, seven or eight times a year. It gets a major service every three years. The 550 is back on the Factory recommended schedule.

Those are the limits I have set for my cars. It's worked out well for the past 13 years.