The modal structure will change and stress will be concentrated at the weld.
OP: thanks for sharing, you may save somebody in the future. To the peanut gallery being a-holes about it, you're not helping anything and probably preventing future users from sharing valuable information in some misguided attempt to pat yourselves on the back. Instead, you give Ferrari DIY'ers a bad name.
Sorry Pete but if I was the OP I would be jumping of FChat and telling people I ignored a potentially serious problem for 5 years and was lucky to get away with it. There is nothing valuable in the OP posts. Even his conclusion about the quality of the SKF bearing is bogus because he has no idea why the bearing seal failed. SKF bearing are crap is just another FChat myth. You know, it's the if one fails they all will attitude that often prevails around here. Anyway, if he looked into it immediately he might have found some telltale evidence of why it failed,...or not. I seem to recall a few years back that you had an oil hose let go at VIR and you shut the engine down immediately. Of course, you were smart enough not to ignore the warning sign of the oil pressure warning light or low pressure, or whatever triggered you action. What the heck, you could have kept driving assuming it was just the gauge or sender,.... Also, back around 2014 after I did an annual oil change I heard a squeal when I started the engine. Sounded like a bearing or at least metal to metal. Shut the car off immediately and didn't attempt a restart until I was some what confident I found the problem. Turned out I dripped a little oil on the alternator belt and it was slipping. No big deal. I could have just drove it that way. But that's not the way this ****** works. If there is a lesson to be learned here it's don;t do what the OP did. It's a bet you may loose.
There was a big issue with counterfit bearings coming out of China a number of years ago. They even came in SKF box's with the date etchings etc. It was so bad Daniel stopped selling the SKF bearings altogether. Perhaps you fell victim to a set of the counterfeit units.
Hill Engineering use NTN bearings for their tensioners, under a strict: "supply us only!" contract - So you can't buy the bearings yourself from NTN. According to the Hill Engineering website, the bearing's have been designed to match the SKF bearing at a minimum, and have an improved/superior seal design. I deal with bearings and bearing failures in all manner of high speed applications, and NTN are pretty much on a par with SKF when it comes to quality, they're not night and day superior. NSK are also pretty much on a par with NTN and SKF. From personal experience, I'd say Koyo are slightly superior to the NTN, SKF and NTN, especially for high speed applications. Just below NTN, SKF and NSK come the likes of F.A.G , and Barden bearings. Something to be aware of: There are an awful lot of fake bearings that come out of China, that packaging-wise, can be very convincing. The bearing markings look almost exactly like the originals too, but the quality of the actual bearings is a joke! - Cheap, weak materials, and made to pretty much no tolerance whatsoever. Even bearing grease is starting to be being faked! (Again, the packaging is very convincing - The grease itself is a joke! ) Something that gets overlooked when it come to bearings, is the fit to the shaft and/or housing that they fit to. A few microns ovality can cause the bearing to run hot, and reduce the bearing life dramatically, due to the grease overheating. Another issue can be from how the bearings have been stored, handled, or fitted. People underestimate how delicate bearings can be. The slightest knock on a bearing, or hitting the bearing races with a hammer or pin punch, can create microscopic damage, that can cause all manner of failure conditions for a bearing, including overheating (let's be honest here: Most car mechanics/technicians are not noted for their delicate touch! ) Far too many people jump to the conclusion that a bearing failure is automatically a manufacturing issue, declaring: "These bearings a cr*p!". The reality is, when it comes to high quality bearings (Which SKF bearings are ), failures are very rarely due to manufacturing issues - They are usually caused by incorrect bearings being selected for the application involved, incorrect sizing / pre-loading, poor storage/handling/fitment, or external issues affecting the bearings. Anyone who thinks SKF makes poor quality bearings, should really pay them a factory visit if possible, and see the attention to detail that goes into their bearing design and manufacture - It's quite an eye opener. (I've been fortunate enough to visit both SKF and NSK factories over the years -There's far more to bearings than people think! )
So are we saying Ferrari was incorrect to weld their own drive pulleys? Curious to know why the pulley fences were welded on the F360
Belts can walk back and forth on pulleys for a few reasons and the fence is there so the belt will not walk into the case cover or the case itself — it’s just a small helpful thing to prevent a lot of problems—- to tach it in you are putting a small amount of heat and weight in the part with little distortion or compromise to it —- welding is more heat , distortion and weaknesses the part and adds more weight which can possibly off set balance and create vibrations —- I know it might be small but a lot of engine builders and manufactures spend a lot of time removing these things for a reason—- and there is another thing to look at it is cost between the 2 types a tach is fast and cheap a weld takes time and will possibly need some machine work after As far as what comes from China yes a lot of counterfeit produces are flooding the world —— when manufacturers started using the cheap labor they allow this to happen—— when the same factory is making both parts for the manufacture and for the “boot ledger” who’s to say the factory doesn’t throw in some bad ones with the ones that should have been right Everything you buy is junk even A/C Deleo moved 40% product production back state side because of this so buyer beware and thank open trade agreements which is only going in one way —-not for us —— Sent from my iPhone using FerrariChat.com mobile app
Yes, this is much better than your initial one-line BS response. I encourage you to challenge all my statements. Criticism is what moves the world forward. So, please put some effort into it and note that it requires skills to give the right criticism.
Thanks for your perspectives. Highly appreciated. I mostly buy NTN and SKF bearings. I consider SKF high quality bearings, and this is the first time I have had an issue with an SKF bearing. I am disappointed and surprised that the seal for a £250 bearing (Ferrari 167464) fails shortly after it was put in service. I have no indications that these SKF bearings are counterfeits. They feel as solid as the Hill Engineering ones that went in.
Just more info. Here is SKFs recommendation for storage life on sealed bearings. THREE years, due to lubricant oil and thickener separation. And another link to supplement 4rePhill post on bearing failures. https://www.skf.com/us/products/super-precision-bearings/principles/general-bearing-knowledge/storage https://www.skf.com/in/organisation/about-skf-india/skf-india-blogs/bearing-life-and-bearing-failures
That's actually very interesting, and another reason to use these cars and not leave them parked up for too long.......the old "its only done 3,000miles from new" is actually a red flag to me on a car of this age.....much rather buy one thats been used and maintained...
Following up my initial post with some more information. I have contacted SKF and Hill Engineering and got some feedback that might be relevant: SKF confirmed that the SKF bearings marked W23G were produced in week 23 in 2010. Hill Engineering confirmed (based on the batch number) that the PT355 bearings that I fitted this summer were produced a few months earlier. Hill Engineering recommends their bearings to be fitted within 2 years of manufacture. Hill Engineering has a proprietary design for the seal developed with NTN. Obviously they will not disclose too much detail about the technology. Hill Engineering also informed that they have seen plenty of seal failures for tensioner bearings with Ferrari part number. They speculated that over-filling of grease can cause a tiny rupture/defect in the seal, which will then continue to leak out grease in small amounts over time. Some people have asked me what the bearing noise sounded like. The noise level was fairly low and when standing next to the car at idle it was not possible to hear the squealing. The sound could be heard when I put my head into the engine bay next to the oil tank or near the ground in front of the right rear wheel. Now I have established a way to inspect the right side tensioner bearing with an endoscope camera, so I will add a camera inspection of both tensioner bearings to my oil change procedure.
It is my third time I am using a SKF tensioner bearing with no Issue (once when had a 97 spider , second time on the Fiorano) when got the bearing from Ferrari, I have noticed they changed the color of the seal to black from blue. I guess of better improvement.
I appreciate your post. Glad you got it sorted out. I wonder if belt tension or some other factor is causing failure of these tensioners? Some people above feel your tensioners were not replaced-when they should have as part of the service. If that is the case, with such an untrustworthy shop/mechanic, I wonder about the belt tension. In some ways I respect that Ferrari and Porsche etc. stick to the formulas that work-meaning they sometimes don’t change things in the name of progress. Still, can’t say I am not envious when I watch youtube videos where, on a Mercedes for example, the tensioner is easily wrenched out of position to release the old belt. And then released to apply the correct tension on the new belt.
I know this is an old thread BUT, I just ordered the cam tensioner kit from Superformance and received the Dayco belts plus SGP bearings which I have never seen before , never even heard of them, always been SKF man. Anyone used these and can give some feedback please ? My 355CH always gets the best but I'm concerned about the bearing Cheers John Image Unavailable, Please Login
I bought those bearings from Superformance thinking I was getting SKF and decided not to fit them to my car. They are an unknown quantity and looked a bit shabby to me. I feel that these bearings are misrepresented on the SF website, they show a picture with a blue seal which what the factory parts have and they refer to Ferrari part numbers in the listing. The price is basically in-line with buying from Ferrari UK, so it would be easy to think you’re buying SKF bearings. It’s not only bearings, but other parts where Superformance quality and customer service has notably deteriorated over the years. The final straw for me was when I called with a query about my order and the man I spoke with was downright obnoxious and rude. I now mostly buy from the official Ferrari parts place in UK, they have a very fast delivery and OEM quality. Prices are not that different. I will never use Superformance again because I don’t trust their quality and I don’t appreciate someone being a jerk to me when I just dropped 1k with them in parts.
Simply having a genuine SKF marking does not assure a quality product. At one point genuine Ferrari tensioner bearings for some applications SKF bearings were being used in the tensioner pulley assembly. Those pulley assemblies were constructed for a Ferrari contract by a 3rd party using SKF parts. It was not a quality product. The bearings selected were not suitable for the job despite their producer who had no control over their application. I do believe for the particular application we are speaking of there is more than one quality choice but there are also bad choices and unknown quality choices. Hill is one company that from my experience has so far never let us down.