CAMBELT REPLACEMENT EXPOSED

Ok, I guess it's like going to the dentist then.....??

So come on.. what are US Ferrari shop labour rates??

 

Here in DFW, at least $91/hr, and more at the dealer. "Major" services are usually quoted in the 3K range. I've noticed that it's MUCH cheaper in the UK for some reason.

There's lots of rumors and misinformation about belt changes, and Birdman is just trying to get real-world information. Me, I'm sticking to the factory recommendations of 52,500 miles on the 328. According to the records on my car, the first belt change in my 328 was done at ~ 50,000 miles by the previous owner, in 2002.

 

im an idependent and charge between $45 and $85hr.i find it interesting what the shop owner charges.when i paid the overhead for a shop i did charge more but only for what i did to he car.prices seem to go up when there are more people in the food chain.i like the small shop that have a start finish deliver approach.forzafrank

 

Here in the San francisco bay area, it is $120-$130 / hr for BMW and Porsche dealers. For Ferrari dealer (there are 3), it is a tad higher. There is always the profit adding costs of parts ($30 for a bushing), and a noticeable % adder for incidentals (like shop rags, parts cleaner, etc). There is always the dishonest dealer to deal with (the one that charges for all 16 valve shims while they change only 2). And, of course, there are the imcompetent ones passing themselves off as mechanics. That is the reason why this board exists.

 

Phil:

the rates can vary quite a lot, heck if I didn't have to pay $5K insurance every year, and worked illegally out of my house without investing in training, books and equipment, I would do it for $50 per!

My annual overhead averages $500 a week at least, so I charge what I consider fair for my time and experience, currently $84 per hour. My accountant and legal charge WAY more than that.

At this I still make less than the parts changers at the local Fraud and Generic Motors dealerships.

As for the original question, I have had 7 3x8 cars towed in during my 15 years with slight to catastrophic engine failures from belts stripping. One came back 5 days after the PPI and the purchaser ignored my advise to "do the belts" as insurance.

You can take or leave it, your $$.

 

for what it cost to svc the tensioner [clean and inspect ,replace part or replace bearing in part]it is inexpensive.there are others that dont change idler unless its needed.

 

I believe there are two issues to be discussed:

1) - Engineering considerations and belt experience
2) - Sales and company reputation

I commend Glassman for his approach to this issue: "What is the experience - not folklore"

My experience, and it appears this mirrors many others, is that belt failure is uncommon. Everyone agrees it is expensive should it happen, but uncommon. Furthermore, engine out belt changes for 12 cylinder cars is not a $3,000 bill. Multiply that by 3 and you are close. Yes, it can be done for $5,000, but when the engine is out, the same mentality leads to water pump change, tensioner change, radiator re-coreing, fuel pump, fuel distributors, and on and on. The cost quickly rises.

Can the belts tolerate 10 years and 60,000 miles? This IS a statistical question. The real analysis would be the likelihood of belt failure over time and mileage. Clearly there is an ascending curve with time and mileage.

Putting this all together, I would be ahead economically if I did not change the belts, but waited for failure to rebuild the engine. The combined 60,000 miles and 40 years (for my 2 twelve-cylinders) before 1st belt change would have cost me 8 recommended engine out services (on a 5 year schedule) at $10,000 each. I am clearly ahead of the economic curve. I could have afforded 3 new engines.

If these were airplanes my analysis would lead to a different conclusion.

In summary, I believe Ferrari recommends belt change every 5 years to avoid the perception of frequent engine failure. Who would purchase an inordinately expensive car that carried a reputation of frequent engine failure? By pushing the services closer together, the statistical likelihood of catastrophic failure goes down, the company avoids the reputation of poor engineering, and the cost is shifted to the shoulders of the vehicle owner. Not a bad approach.

Jim S.

 

Ah the old belt question....(!) ....or should that be "the old belt and tensioner bearing question" ??

Here in Europe (as most know) we get stitched up with a c25K mile/2 year replacement cycle on 308s & 328s. I believe its 3 years on 348s & 355s. The same belts can apparently last upto 5 years in the States - go figure.

Speaking to the independent techs here they all say the same thing pretty much - they think (know) the belts will last longer but they can't recommend against what Ferrari say. They also say they wouldn't leave them for 5 years to safeguard against material degradation. The effect of this can vary between cars depending on how they are used (less is worse!) and how/where they are stored.

To keep this in context I have a VW and an Audi on my drive as well, both of which are notorious cambelt/tensioner breakers. I wouldn't leave those for more than 5 years/60K miles - despite what VAG say (80K or 100K miles depending on the engine). Then again, having changed the belts on those I can also say that the belt run is far less acute in terms of the angles the belts turn through. Those engines also get used every day and never get revved to 7.5K So a 5 year interval is more realistic I think.

I've had my 328 for 6 years and I have changed its belts every 2 years (I only average about 1500 miles a year). In terms of comments and experiences relevant to this thread, what I can add is that when I had the belts changed two years ago they also changed the tensioner bearings (to a slightly modified version that QV London do). I saw the bearings that came out & they were definitly a bit rattly.

The point is that this was only two years and maybe 3.5K miles after the preceding belt change which was also done by QV and there is no way they would have left the bearings in previously if there had been the slightest hint of an issue with them - they've been servicing 3x8s for far too long to make that mistake. Had I tried to go for 5 years from the preceding belt change I would almost certainly have had a bearing failure with a probable result not dis-similar from a snapped belt.

Having had the bearings done my inclination is now that a happy medium is some regular use of the car (to ensure that the belts do not sit in one position for too long) and a 3 year change interval. With the cost of the belts its just not worth the risk of stretching this out to the limit and beyond.

Besides that the V-belts all get replaced at the same time so its useful preventative maintenance & allows you to check the condition of things like the water pump & alternator as well. Some of these cars are well over 20 yrs old now after all.

For anyone with a 3x8 where the bearings have not yet been changed then I'd recommend a shorter interval and a pre-emptive change of the bearings at the next belt change anyway for peace of mind - the bearings are not that expensive. Once these have been renewed then a sensible happy medium is the way to go based on the way you use the car and what you feel comfortable with knowing the likely cost of an engine rebuild - which will be many, many times more than the cost of adding in a few extra belt changes over the remaining life of the car (or your ownership of it). For 348s & 355s the belt change is obviously much more expensive because the motor should be dropped so that maybe has to be factored into the equation somewhere.

The one thing you don't want to have to do when you jump in your Ferrari on a nice sunny day is to worry about having to "baby" the engine. As we all know they perform best when given some serious stick! Driving around with that nagging doubt about "will it, won't it fail" is not for me - but others may disagree and YMMV!

I.

 

At 82.5 inches in length, owners of Porsche 928's have reason to be concerned about the timing belt tension for their cars. While obviously not a Ferrari, the 928 is of the same era as our 3x8 F-cars, being made from 1977 through 1995.

To monitor the tension of this massive belt, 928's have a single, cheap spring that contacts a switch to Ground so long as the belt tensioner has enough tension in it (i.e. from the belt).

A loose belt allows the spring to expand, the switch no longer contacts ground, so a Belt Tension Warning Light flashes on the dash light for the driver to see (and correct, one presumes).

According to Wally Plumley at 928 Specialists (a noted and respected Porsche figure), this simple, inexpensive belt tension warning system has saved countless 928's from catastrophic belt failures.

He writes:

http://www.rennlist.com/techarticles/928/928enginefaq.htm#Belt%20Tensioner

Oh, one other thing. Wally notes on the RennList website that *age*, not mileage or RPMs, is the biggest destroyer of belts. He suggests replacing the rubber timing belt on those cars every 5 years to be safe.

 

Not questioning your finances.

I do think you need to drive it more. Hell, I'm flying 8000 miles to drive my 308 in three weeks...

 

I prefer no light, having seen the idiot lights & sensors in US cars fail, so weren't there when needed. Don't trust them, so check my dipstick & if necessary install an oil pressure gauge I can see working.

Where did you come up with $15 for a belt tension sensor?

It's not a simple problem to come up with one. There's very little space to mount anything inside the cam belt covers. The tension senser would have to apply pressure to the flat side of the belt, meaning it'll need room to roll, and will have a bearing that will fail.

Then you'll have to make sure that the tensioner's pressure doesn't exceed the belt's limits, & the sensor doesn't let the belt tension vary enough to jump teeth or cause other problems. Doubt one could be mfg'd & installed for less than several hundred/bank, expecially since the volume is going to be quite low.

Think I'll stick with my 5 year/30K changes & put aside the money for other repairs.

Sounds like the 928 tension sensor is built into the tensioner mechanism. A reasonable way to do it if the tensioner bearing isn't locked down the way the 3x8s is. That lets them get the cost down.

Only if it weren't properly designed & thoroughly tested.

Umm, wonder how many engines you'd have to go thru before you got it right...

However, it's economic value is dubious, especially if you're doing your own service. I can't see it increasing my belt change interval time or mileage.

 

I was simply quoting the price that I remembered for the Porsche 928's timing belt tension sensor (a single cheap spring that makes or breaks contact with Ground based upon the tension that the timing belt places on the tensioner).

No, if one copies what Porsche did, the spring simply needs to be held back by the tensioner (based upon the belt tension), not held back or otherwise touching the timing belt itself.

That won't always be the point. Should the belt tension warning light go on PRIOR to your regular service interval time, you'd be wise to advance your shop time, for instance.

Many posters, some in this very thread, have said that they've had loose belts at 6,000 or 8,000 miles.

You, without your "idiot" light, wouldn't know if you had a loose belt prior to a scheduled service interval. Too bad. There you'd be, on the side of the road with a $20,000 blown engine, while old Porsche 928 drivers (who have been reported by respected Porsche authorities to have had numerous engines SAVED by their timing belt tension warning lights) drive past you...as will I, especially if I can figure out how to put a similar tension warning system onto my Ferrari 348.

 

Sure, you can tighten the tensioner up by design.

That being said, look at the two images below. The first sketch is the 348 engine, with the idler/tensioner in red.

The second picture is a Porsche 928 idler/tensioner with the cheap tension switch.

Now really, how much effort would it take to make a similar switch work for our 3x8 series timing belts?!
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Does this take in to account shelf life of the belt stored? or once it's been mounted on the car and run a few times.

I know Wally is not here to answer it, but would that follow a logical thinking?
(speaking timing belts in gerneral)

 

It's a valid question. Shelf life does matter, but not nearly as much as the time that the belt spends under tension. On the shelf, there is no tension stetching the belt. Heck, it's probably something like dog years to people years in comparing viable life-spans for belts on the shelf versus belts on the engine under tension.

 

I've done my own majors on my TR, 348 and F40. I was into it for ~1200US in parts and 30 hours of my time..........and the cars ran perfectly.

I decided to treat my self to a 'dealer' service at SF, and they trashed my TR's engine and tried to get out of their responsibility. They did a subsequent one on my 348 to make up for their 'error', and made incompetent mistakes. To answer your question....the 'stealers' get between 5000-8000US for a major service in the US. Americans are idiots for paying this.

 

You CANNOT retension the belts at least on a 308. The belt stretches and takes a set, once it has been tensioned the factory reccommends replacing the belt. I have done as little as 15 miles and replaced the belt as it is only 19$ or so!
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I notice in the photo that the front pulley is not fitted. This is essential to be fitted, as the helical drive gears behind the front cover can move without the pulley, causing timing errors.

 

im wondering if small cam seal leaks will effect the life of the belts. on my daily driver, the cam belt broke because leaking oil deteriorated it . would the oil actually get on the fcars belts?

 

Well, in a Ferrari, you know that it's too loose if you can hear it squeal (and by then, probably too late, too)!

But seriously, right now we've got to stop the car, schedule maintenance, and use a tension tool to measure to see if the belt is too loose; a difficult thing to do considering the belt is covered and buried in the middle of our cars (well, for 348's).

What would be better would be if we had an automatic way to tell us if our belt was too loose (even while driving), such as by using a simple $15 spring-loaded switch connected to our tensioner pulley.

Technically, 348 owners are supposed to have the dealership check our belt tension every 15k miles, but that does us little good if we get a loose belt at 6,000 miles.

We need a tension switch/sensor. I bet that we're all good for the extra $15, too. Ancient Porsche 928 technology is not beyond Ferrari's reach, either.

I'm surprised that some of the pros on this board aren't already offering this switch/sensor and installation service. Kermit/JRV/Ferrarifixer/DexM and numerous FerrariChat sponsors should be all over making and selling this switch for us. Heck, I even posted the picture for it above. It's one wire, one bolt, and one metal to Ground contact. Oh, and one light (and the tiniest of circuits, a simple NOT gate) for our dash.

This tension switch should be going onto *every* 3x8 series car during every Major service, and frankly, Ferrari itself should mandate it.

You heard it here, first.

 

Just to follow up on all of that, my proposed timing belt sensor switch should be wired to the Ignition such that we can see if the tension on the timing belt is too loose, even prior to each Start.