Tensioner Bearings

My 88.5 328 is apart for a cam belt change. The tensioner bearings are 6 years old and have 18,000 miles on them. They look and feel perfect! Should they be replaced? The next belt change will be in 5 years with no more than 10,000 additional miles. Thanks for any input. Gary

 

Replace them. For less than $150 for the pair, it's one less thing to worry about:

http://www.ricambiamerica.com/product_info.php?products_id=224308

 

I have been informed from the some very knowledgeable mechanics that they do not NEED to be replaced if they look and feel perfect and that it used to be common practice to inspect rather than replace the bearings. That being said, I would replace them. In my opinion, given how cheap the are, why not replace them so you never have to wonder what if...

Just my .02

 

Replace them regardless. Cheap insurance. you *really* do not want one of those going wrong

 

When labor was cheap and parts were expensive we used to just inspect them. That is no longer the case. Also we could count on the average Ferrari owner to pay attention and let us know when there was an unusual noise. We can no longer do that either. We also used to be able to count on the parts Ferrari supplied us. Thats another thing we can't count on. A tensioner bearing will make noise before it fails and I can think of a number of instances here where there were catastrophic tensioner bearing failures at the cost of an engine. Those had to make some noise yet no one noticed and the motor paid the price.

SKF bearings are just not that expensive, just replace them.

 

I would also check, very carefully, the drive pulley outer bearings. Look for oil leaking and any side to side movement of the pulley shafts. There should be none.

 

Brian,

my 88 had 14k miles on it when I got 2 years ago with a one year old major on it by a dealership. The tensioner bearings were not replaced. I believe they are original from new.. (the car now has 17.5k miles on it, 3.5 years and 3k miles since major).

After about 1k miles of my driving it, a very intermittent squeal began when cold, and low rpms, but would seemingly dissappear as the car was driven. That squeal has slowly grown to the point of being able to hear it more of the time, when hot and even at high rpms the squeal can now be heard.. I'm not a mechanic, but, to me , this is not the typical sound of a normal "fan belt squeal" (like on a normal car) so much as what I would think of as sounding more like a bearing.

Since the last major was done 3.5 years ago, I guess it may be a moot point since it's due for a major now anyway. But does this fit the description of what a tensioner bearing might sound like when one's about to let go?

Obviously you cannot diagnose my car over the internet. Just wondering what a bad tensioner bearing might sound like, if you can describe how one might sound before it goes bad with any degree of consistency? Would it be very loud at all rpms? Or just "discernable" a sound, as this one is?

Thanks
David

 

The PO of my 80 GTBi had the belts and tensioner bearings replaced due to age (not miles -- he barely drove it), but went against what his mechanic advised and did NOT have the water pump replaced. Fewer than 4000 miles later, with me as the new owner, the water pump bearing started growling and moaning. I took it off to change it (doable by removing the belt covers), and it was almost seized. I don't want to think of what would have happened had it been the belt rollers instead.

 

There's no documentation of any water pump rebuild with my car. So I can only assume it has never been rebuilt either.

So my thinking now is to just go ahead and have it all done at this time.

 

You're right, I can't. I'd have to hear it.

 

Just my experience...
1986 328, 30000 miles, both water pump and tensioner bearings original. Inspection of the bearings proved them ok so I did not replace.
Ciao
Eugenio

 

In my case, when I got the 89, I went over the whole thing and replaced T belts, bearings, and rebuilt the water pump. Both the belts and the Water pump were OK but they were cheap enough and that I did it. The valves did not need to be adjusted so I did not even open up the top. No leaks either so no point in replacing the seals.

I did replace 95% of the fuel and water hoses. Most of them did not look like they needed it but ... I still have to replace the filler hose, and the 2 fuel hoses at the bottom connecting the fuel tanks, but ... I will leave those until next year. Too many projects at home.

 

Here is what I did when faced with a cold-start-only noise similar to the one you are describing. I couldn't tell by ear where the source of the noise was. My tensioner bearings were replaced about 2.5 years ago, so I was thinking it shouldn't be them. But that is not something you want to risk, obviously.

Get a mechanic's stethoscope, and unscrew the cap on the end that holds the metal rod. This will leave you with a funnel shaped plastic cup attached to the tube. Start the car and get the end of the stethoscope close to the usual suspects. It will amplify the sounds coming from just that area and cut down other ambient noise. Be careful not to get yourself caught in moving belts/pulleys. You will be able to easily tell where the noise is coming from. For me it turned out to be the alternator, so I have a new one ordered.

Easy procedure to locate and pinpoint any mechanical noise.
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