Evening, After sterling work with Hill Engineering tool, i have changed the belts and tensioner bearings and refitted and torqued the damper pulley. Rotated the crank 6 times and marks all still align, quite pleased with myself. Before i started the job i checked the tension on the belt using the Gates App - it is well liked on the Ducati forums. Before 95hz, did seem looser than i would have thought. Once i fitted the new belts and "released" the tensioner i got reading of 81hz. To increase tension i had to leverage the tensioner to compress the spring further, but managed to get exactly 126hz out of one side and 120hz out of the other. Car is a 1999 550, and i believe 126mz is the correct tension Is that the correct way to adjust the belt tension ? Thank you
Ferrari updated the procedure on the 612 (also an F133 engine with the same belts) to use the sum of the frequencies on the two spans on each belt. Image Unavailable, Please Login
Thank you for this. So it needs 4 measurements in total !! Do they make it difficult for any specific reason.... So my 81hz on the longest stretch probably wasn't actually far out. Will try again tomorrow. If i need to increase the tension is it simply a case of leveraging the tensioner body and then tightening the nut again ?
Tazandjan, Looking at some earlier posts you offered, 126hz appears to be the original measurement, and the 335 - 360hz is the updated offering. would you deem 126hz as being incorrect now ? thanks
Funny. I remember the frequency as the "middle Finger" as in frequency of middle F but I still do this incorrectly by feel. That's just the way I have always done it since the 308's
I wish the answer was 100% but I know from experience that it certainly is not… Anyway, what % of shops actually (and correctly) utilize such a tool ? Amidst a shop comeback following major service here in LA the owner claimed “nobody” he knew used them, “they were expensive” and if I could borrow one — from the mechanic that spotted their error (very loose belts !) — that “they would use it”. This was after my car was towed back to them a second time following my belt service/major. The worst $10k I spent overall. Venting now but still…just because a car has/had a major it means very little. I would prefer buying one running well “due” for a major. Any day. Every day.
Hopefully you found a new shop. A good tool can be had for around $250 and there are also apps for smart phones that work quite well.
happens all the time…in the old days there was steager tensiometer to tension belts. In the early 80s I apprenticed as a Ferrari mechanic for a known Ferrari mechanic in LA. I got to know people in the industry and several FNA shops. I asked about steagers and not a single shop had one, not even FNA shops. I was curious to hold one in my hand.
Didn't you mean to say instead that you had to depress the spring further to increase belt tension? Check this thread for a good discussion on timing belt tension. What tension did you measure on the short stretch of each belt, between the tensioner bearing and the lower cam drive?
Complete bull ****. Dealers were provided them by Ferrari. They had no choice in the matter. For years after all the independents I knew had them as well. I really do get it that you are the greatest mechanic of all time but you really do need to quit just making stuff up.
Yes that is correct i had to make the belt tighter, which required pushing the pully towards the belt. I haven't done that yet, i had to do some work today, it will be the weekend when i get another chance to play with it, but i am there or thereabouts. thanks
Evening, Put it all together this morning; Using the Gate Belt App i could get those numbers consistently. 121hz and 230hz = 351hz on one side and 111hz and 241hz = 352h on the other Alternator belt 118hz Water pump belt 101hz Thank you for your help.
I'd never on any other car tensioned the cam belt(s) using the frequency method, but I was pleasantly surprised how easy, convenient and consistent it was. I had the help of my sister, who is a professional musician. On the first belt we had to practice a bit, but the second one was a 10 minute job. My sis just listened to my pinging and tapping and told me tight or loose, and she was only a few Hz off when we checked the final result with a sound meter.
No external mic, just held the phone as close to the belt as possible. I used both an I phone 8 and my son's 13 and they got the same recording. Car started and ran fine, but will need a longer run later this week. Image Unavailable, Please Login
Did this a few years back with gates app. Bought a cheap amazon mic for my iphone and clipped it on a bolt next to the belt. I got the idea from the guitar tuning apps on the iphone. If the iphone can tune a guitar, it can tune a belt.
I just grabbed an old acoustic guitar, placed it on a table near the front of the car, set two of the strings to the pitches (notes) I wanted, and pitch matched much as I would do if it were a musical instrument. Quite easy actually.
