CAMBELT REPLACEMENT EXPOSED

Maybe I will add again my thoughts. I have never seen any other car with cam pulleys as small as on a 308. Easily half the size of any Jap car I have ever seen. Smaller pulleys equal tighter radiuses the belt must bend around. Most of the cars people quote with higher milage belt change intervals are non interference motors so if a belt breaks, no big deal. But camshafts turn half as fast as crankshafts, and figurig most 308's are run in the 3-5000 rev band, it has to be scales of magnitude harder on the belt, all things being equal. No other cars out there really operate at that high of engine speed in normal driving. But this is all subjective.

Most of the people who blow a belt will never admit to it, to ashamed they neglected the car, dont want the record on the cars history, it never happened. Many also want to be able to resell thier cars and dont want to help the reputation these cars can grenade themselves, so its possible this thread wont be able to offer the info we would like to see. I also feel the other post about to many opinions gets in the way of real opinion, so we are all over the place. The only true answer is the one about how you will feel when your belt does break, and causes untold $$$$$ in damages. I already know they can break, I have known it since Fiat invented them, and have seen many broken belts on "other" cars. But I personally knew someone who blew up a 308 from a belt, and it wasnt pretty. So like the man said, maybe we have to just make our own opinion.

 

I'm a firm believer in lifing things in terms of rpm completed and not actual mileage.

We all drive differently, and some guys can kill a car in no time, while some will drive very sensitively. A 30,000 km car could easily be in far better condition than a 10,000 km car.

Brief note for Chris morse re 4 litre thread... Thats all about the lower drive bearings, not the tensioners....

550 cambelts... Recently had a kevlar strand type introduced. I swear I was told by a senior Ferrari technical adviser that they were now a 5yr life, but now the dealers are saying the old ones are 2 years and the kevlar are 3 years. The 550 service manual says 3 years for the old ones, so who do we believe? And what are those that tell us these things seeking to achieve??

As an independant I can follow my own rules, and I concurr with spang.... I say 5 years, regardless of model/belt type/mileage within reason. If you regualrly track the car (~10-25% of total useage?) I'd change them sooner... say 3 years. Lack of use and cold weather massively reduces their flexibility, and this is when they will most likely give a problem.

 

I do my belts on my 328 every 5 years. I've owned the car for 17 years. The tesioners are carefully inspected and compared to one another at that time. Whether I change them (tensioners) is subjective.

 

I bought my 1986 328 in November 2003. One owner, 12.000 miles, still on original belts. Just slowly drove it to the garage where belts were replaced.
Looked like new, but who cares.
Bearings were tested and not replaced because of, again, like new conditions.
Ciao
Eugenio

 

My 328 had a major service in 06/99 @45,000km, and I just did another one 06/05 @ 58,000km. Car had regular use in the summer, in Calgary, Canada which is high altitude and dry. Car was put away in the winter. I only heated my garage to just over freezing i.e. 5deg C.

I saved all the parts from the major. The old belt integrity wasn't compromised, but there was some slight nibbling to the edges. The new belts were considerably more supple than the old ones though. Bearings were changed last time, and were fine. My mechanic said it was a good idea that we changed them because they were dry.

Time to failure? To the layperson, it looks like the belts wouldn't have failed any time soon, especially as I drive sympathetically, and run mostly on the open road with cool engine temps. But, I feel *much* better with the new ones in. I get a warm feeling inside knowing all my machines are maintained fully.

For me, I think I will do the belts every 5 years. 2010, 2015...it's easy to remember!

Cheers, Lawrence.

 

PO had put 25,000 miles over 8 years on belts. PPI revealed that the tensioner wasn't working properly and the belt was slightly loose. Yikes! Luckily no harm done. Time for a belt change. How long was the tensioner bad? Who knows?

I tend to agree with Lawrence. 5 years on belts seems to make sense. My Volvo required a new belt after 60,000 miles or 5 years. Why should a Ferrari be expected to go longer?

John

 

I've only had *one* belt failure, and that was on a 1995 LT-1 Corvette (daily driver in a hot climate, stop-light racing, etc.) at 53,000 miles when it was 9 years old. Of course, belt failures on LT-1's are insignificant; the engine ran off of the battery (instead of alternator) and I simply drove in to the Chevy dealership to have a new one installed. Took an hour and cost me $100.

The failure itself was at startup, on a hot start. Turned the ignition key and heard a loud POP! Then the dash warning lights came on.

My old Porsche 928 is supposed to have a timing belt sensor that lights up a dash warning light if the belt tension isn't tight enough, but after 60,000+ miles and 19 years on the original timing belts, I've never seen it. Even so, that car is headed for the junk yard even as we speak from a myriad of other problems (too bad).

The Prior Owner of my Ferrari 348 Spider replaced the timing belt at 11,000 miles during one of his "warranty card" services several years ago. I guess that's fine, especially if done under warranty for whatever reason, but it seems like overkill.

Discounting my 928 experience and looking at the Corvette experience, there is NO WAY that I'd go 9 years and 53,000 miles between belt changes on my Ferrari 348.

But I'm not going to pull the engine (or gas tank, if that's the way some want to change 'em) after every day's drive, either. Like you, I want more real-world input from F-car drivers (garage queen museum attendants need not apply) to sort out a more reasonable maintenance period than 11,000 miles or 53,000 miles. Neither extreme seems appropriate for a 348.

 

You'd think that we'd be able to get Kevlar or Nylon belts made for our 3x8's, too. Surely there is *something* out there that lasts longer than factory rubber belts.

 

5 years on rubber belts is probably fine, but 50k miles on a 300+ hp engine timing belt would probably stretch (heh, heh) the limits.

Kevlar, Mylar, or other hybrid belts should be able to go longer time frames (perhaps 8 years), though we also need to know how they'd handle mileage.

Come up with a hybrid composite timing belt, waterpump, and tensioner system that can last 8 abusive years and 45,000 hard miles and you are going to make a lot of 3x8 owners happy.

 

Yeah. A timing chain!

Pardon my ignorance, but why doesn't Ferrari use timing chains rather than belts? One person has told me that it's a weight consideration. I'd certainly be willing to give up a couple of pounds of performance for the peace of mind of having a chain rather than a rubber belt (if that's the issue).

And my apologies for not directly answering the premise of this thread. But I couldn't resist asking about the chain...

 

Actually, the existing 348 engine design probably could handle *both* timing chains and a master belt; timing chains circling each pair of overhead cams, but beneath the existing rubber belt.

But whether that setup (i.e. the chains still keeping the overhead cams in synch) would still protect you from engine damage if the overall existing rubber belt failed is debatable.

 

There have in fact been several belt failures posted, including pix of the dinged pistons. Most of them are in the Old fchat archives.

IMHO, the poster that said that people experiencing belt failures aren't going to admit it is right on.

There have also been a couple of near misses where a belt had 1 or 2 teeth stripped off of the inner cords.

BTW, the belts are not 'just rubber'. They are Nitrile rubber with a polyamid or kevlar cord core. The trapezoidal teeth are much shallower than the serpentine teeth used on all modern belts, hence more prone to skip under marginal tension conditions.

These belts DO NOT STRETCH measurably until enough of the cords have broken so that the rest suddenly rip across & the belt breaks. Measuring belt tension as a failure indicator is like depending on the idiot 'OIL' light to warn of a severe oil leak. Good chance the warning would not give you enough time to avoid damage.

You'll only see 'rusty' tensioners on cars that are daily drivers, or that are washed then immediately stored w/o being warmed up enough to dry them off. The good weather drivers generally don't show any rust on the tensioners.

 

So the question becomes, "Would you prefer an OIL warning light to warn of a catastrophic leak, or no light at all?" in relation to a $15 tension sensor for our timing belt?!

Would adding a belt tension sensor actually be a bad thing??

 

I was able to get my car (78 308) because the prior owner had spit off a belt and didn"t want to pay for the repair. One piston was gone, the biggest piece I found in the sump was the size of my thumb nail.

 

You know, its never too early to fix that.

Take the wife to a nice hotel this weekend about 2-3 hours away and take the 308...

 

You know I just looked at my cars history (its a 77) and I count 8 belt changes in 48k which seems crazy. As a relativly new owner I am lucky and can do it myself so I will continue with this schedule every 3 years as it doesn't cost that much and I will do it as part of a major service. If however I was paying rip off main dealer prices like my cars previous owners did then I would seriously think about only doing it every 5 years. My question is why is it so hard to find a compendent shop to do a belt service for $1200 or so. I mean its just not that hard or time consuming....................

On another note I have 3 other friends who have owned 308s for long periods and none have broken belts causing engine problems. I think the 308 motor is one of the strongest out there and can do high miles with great reliabilty as long as it is driven often the harder the better.

 

Ok, so how much is a typical "belts" change in the US then...

Lets clear up the reason why someone would want to defer this maintenance job... are you being ripped off??

To replace belts only, without doing dial indicator cam timing verification......

It's only about 6-8 hours work for belts on a 308/328 and the belts are peanuts, then add remaining service jobs on top etc.

348/355/TRossa is about 20-24 hrs

BB/TR about 24-28 hrs

465/550 6-8 hrs

360 5-7 hrs

add an extra hour for replacing tensioner bearings and overhauling tensioner units, and add on service jobs/valve clearances etc.

Why would someone feel so strongly about deferring an "engine destruction" preventative maintenance job, as to start an thread dedicated to it's statistical likelihood of happening??

 

Because some people can't afford Ferrari ownership...

 

That's what I'm trying to establish. But is it because Americans are being over charged...??

What is a typical US dealer and independant hourly rate??

 

Glassman,
Actually no. The offending belt was thrown in with the rest of the partially disassembled motor parts and looked OK. Tensioners, drive sprocket bearings, and everything else looked good. I guess I should be concerned, but I replaced everything that moves that might wear.

 

has anyone everheard of a belt that was adjusted and lived.im curious.i just changed belts on 2000 550 that had less than 6000miles.the belts were loose[take my word for it].turns out the car was never tracked but was driven [up to the red] briskly..as well as it should.belts are just that.they should be checked and serviced as needed.its time comsuming we all agree.if you were to see/feel enough of them i feel you could get a better "feel" as to when one could,should,might service belts.forzafrank