Belt tensioner bearings - need/basis for changing?

Re Ferrair 308 warranties: Back in the 80's 12 months/12000 miles was pretty standard across all manufactures. Then it was increase to 24/24000. AMC went to 5yr/50,000 to bolster sales and soon thereafter other manufactures followed. Today there are mostly back to 3yr/36,000, with 5/50,000 power train and 8/80,000 emissions, but vary by manufacture.

As for Ferrari parts, most parts on a 308 are not poor quality in my experience. Parts bin, yes, ATE, Bosch, etc., similar to Porsche of the day. Over 36 years with my QV the only mechanical parts replaced were 1 pair of tension bearing (@ 25 years, still fine), one distributor rotor due to a carbon track (2018), one distributor cap because I couldn't get the screws out when replacing wires (2010), and one air injection check valve due to rust (2010). Every other mechanical part on the car, except brake pads, came from the factory. And based on what I read here, it starts, runs and stops, and stays cool better then most cars that have been dicked with.

 

FWIW, Mopar (Chrysler) had 5/50 warranties in the early 80's. I don't know who else did.

 

Power train only.

 

I don't rely on third and fourth hand information from "well known Ferrari-trained techs" as others might. In fact, since many 308s are 40 year old cars, the likelihood that factory trained techs are still alive is becoming less and less likely. Relying on people who claim they are factory trained is like standing on melting ice. Of course there are a few here and I respect them but I think the preponderance of Ferrari dealership customers would blush at a list of dealerships that still have a factory trained 308 tech on staff.

But more to the point, as for "less than stellar ancillaries", I guess you don't do your own major service work or maybe you overlooked something. Many 308s are on their original carbs, alternators, starters, hoses, calipers, A/C compressors, condensors, receiver/dryers, window motors, fans (both heater and radiator), radiators, switchgear, relays, fuses, gauges, fuel pumps, fuel distributors, etc, etc, etc. Where is all this less-than-stellar ancillary stuff you talk about? Are you referring to the water pump? The belts? The tensioners, light bulbs... spark plugs?

Enzo may have been the poster boy for affectation but he certainly wasn't an idiot

 

Most of the items you mentioned are not known for their excellent performance. Any AC system of a US car from a decade earlier is far superior in performance to our 3x8s. Window motors? C'mon, could there be a slower window? Fuses? Everybody complains about the fuse panel in the earlier 308's - it's the reason that Birdman came up with a better one. The cooling system on pre 328's is marginal. The switchgear is typical, inexpensive components. The slowdown light system is well known for failing.

It's worth noting that many of the complaints that arise here are not strictly due to as poor component but to the implementation of the system itself. For example, the air conditioner compressor was perfectly adequate in many other cars of much larger interior volume but the implementation of the system is poor and the rest of the components are inadequate for the job.

"I guess you don't do your own major service work"
I have been building engines - mostly high-performance and competition - for most of my life. I did that and dyno work with several major, well known performance companies and I do all my auto work other than wheel alignments.

 

Oh my. Most of the parts you mention have nothing to do with Enzo's attitude with road cars. They are Fiat parts in cars built be a company owned by Fiat.

 

READ the numerous interviews with Enzo. He didn't care about the road cars. If it wasn't for Fiat, there probably wouldn't be any Ferraris after the '60's.

All this "as Enzo intended" stuff when people remove emissions or add louder exhausts is wishful thinking or hero worship. If Enzo could have done as he intended, there wouldn't have been ANY road cars. He wanted to build race cars, not street cars. This is all well documented and there are numerous articles from the period confirming it.

 

Okay, hearing that you maintain your own car puts us on common ground. I can agree too with the criticism of the fusebox. With your experience you probably know that after 20 years of use, circuits that draw high current in 308s (fuel pump, cooling fans) expand their corresponding connections at the fusebox rivets. Birdman's solution is a good one for the person who doesn't know which end of a soldering iron to hold. All that is needed is to flow solder across the buss bars and rivets and the original fusebox with its original covers and original fuses is good for another 40 years. In 36 years of ownership I have never had a fuse blow in my 308.

The A/C systems in these cars are fine. The compressors are working well 40 years after delivery as long as the receiver dryer is serviced and the system isn't damaged. Maybe you have forgotten they were designed to run R12 refrigerant, which isn't available any more? When filled with R12 a 308 has great A/C; when filled with R134a, not as much.. This is hardly Ferrari's fault.

As for the windows, that is a service issue. When maintained with more compliant lubricants the window systems work fine. As for 328s having inadequate cooling systems, I'll take your word for it - I have never spent much time in one, though I passed them all the time on the track

 

Have I said this before in this thread?
The Belt CHANGE interval in 1976 was 52,000 miles, with inspections every 15K miles, from memory.

So that would be the anticipated life of the bearing.

The Tech Bulletin on belts I don't recall addressing the bearing, so here we are....

 

I agree but go even further...

A belt change interval does not indicate a bearing change interval. As you noted, there is no mention anywhere (that I have found) in the Ferrari data that specifies a tensioner bearing change at any interval. Most bearing maintenance specs I have seen call for inspect and replace if necessary. Admittedly, back in the day, dealers may have ignored the "inspect" part and just routinely replaced them "while in there." But that's different than a factory spec or recommendation.

Changing unnecessary parts is a traditional car dealer repair procedure!

But once again, the important thing is, it's your car so do what YOU think should be done!

 

From reading Fchat and other sites over many years, it appears belt failure is extremely rare. When it happens, I recall various causes, something flung into the belt area - sometimes a broken accessory belt that in some cases failed from worn bearings in those systems, or the timing belt bearing wore out due to long term damp storage, etc. So I think the bearings get replaced simply to eliminate that issue of belt failure risk. But periodic inspection would seem a proper alternative, and if the bearings turn nicely, and the belts are on a car in reasonably regular use, the risk of failure just from age alone does not seem any more likely thatn in other "normal" cars. If one maintains one own car, the inspection labour becomes part of the hobby. If you get others to do the work, the while you are in there parts verses labour cost does argue for proactive replacement.

 

BMW's belt replacement interval for a 1989 E30 325i Sport, as quoted in the owner's manual: Every 3 years or 36,000 miles - Whichever comes first.

I owned one for 13 years, always serviced by my local BMW dealer, and ever 3 years I'd be reminded by them that the timing belt required replacing, as per BMW's service interval.

Here in the UK, 3 years/36,000 miles was pretty much the standard quoted interval for a timing belt replacement "back in the day".

Vauxhall in the UK had changed their timing belt replacement interval to 90,000~100,000 a few years back. After a couple of years (and multiple reported timing belt failures), they reverted back to recommending the belt be changed every 3 years or 40,000 miles - Whichever came first.

 

You must be talking about a loaded Cadillac or Lincoln Continental because in 1966 the vast majority of American and European cars didn't have any A/C or power windows. LoL d;-)

 

I agree re 1966 though my parent's 1965 Chrysler had factory AC that worked fine. My point is simply that 3x8 AC was poor by the standards of the day...as were their power windows for that matter...and the windshield wipers. AC was common in US cars by the mid 70's - more than a decade prior to my 328 - and was generally capable of freezing you out of the car. I don't think anyone will argue that the air volume and distribution of the 3x8 AC system is rather poor.

 

I have never thought the A/C performance in my 77 308GTB was poor. Granted, I don't take the car out on days when its 95 degrees and 90 percent humidity, most likely because I don't get enjoyment from driving with the windows up. However on those days when I need A/C to clear a fogged windshield or to cool off the interior on a hot day, its been fine. Certainly, the climate one lives in has something to do with this. Ferrari didn't care if you lived in Death Valley or Houston, they built their cars against the standards of the day which weren't US designed cars. And as said before, these were designed for R12 and they perform well with it. The condensor and evaporator core are too small to work efficiently with the R134a most of us are running in our 308s. Aside from that, when I was making my buying decision, A/C performance was as far down on the list as sound system quality and both of these were just after size of ashtray and belt change interval.

 

I owned the same car. First belt change was at about 105k miles, I forget how many years, probably around 6. But the belt got changed because the water pump failed.

 

All this arguments…. And nobody yet talked about the cam and crank bearings

 

Just decide for yourself on the replacement interval and all is fine. I do my belts every three years and tensioners every six years. Simple.

Scientific? No. Just picked something reasonable from known service intervals, failure consequences and efforts/costs.


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