Rotor/cap problems | FerrariChat

Rotor/cap problems

Discussion in 'Technical Q&A' started by bshaw, Oct 13, 2005.

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  1. bshaw

    bshaw Karting

    Nov 3, 2003
    65
    Connecticut
    Full Name:
    Bill
    I'm doing a major on an '80 308i. It's about done, all's gone well up until now. It started and ran OK for about 1/2 hour in the garage, then started running real crappy. We started taking things apart looking for the problem and found that the rotors were hitting inside the caps. One rotor was just nicking the electrodes and chewed up the cap a bit:

    http://b.shaw.home.comcast.net/ferrari/308cap.jpg

    The other rotor hit solid and broke the tip off:

    http://b.shaw.home.comcast.net/ferrari/308rotor2.jpg

    In hindsight, the new rotors are obviously longer than the old ones:

    http://b.shaw.home.comcast.net/ferrari/308rotor.jpg

    Caps and rotors were both new, bought from 2 different Rennlist sponsors. It looks to me like the rotors are either not the correct ones for the car, or were not made to spec. Has anyone seen this before?

    Both suppliers are working with us to figure out what went wrong.

    Bill
     
  2. Joe G.

    Joe G. Formula 3
    BANNED

    Dec 9, 2003
    1,109
    Los Angeles
    Full Name:
    Joe Gazzani
    i think your rotors are defintely too long at the tips

    who did you buy the rotors from exactly ?
     
  3. 412monzaindy

    412monzaindy Formula Junior

    Mar 8, 2005
    876
    Ontario Canada
    Full Name:
    PBI
    There are two different rotors and the 1980/81 has a different part# than 79 or earlier.
    Are they after market?

    Was the cap on correctly and seated using the pin in the housing?

    Use some calipers and measure the old versus new, cap and rotor.

    Run to the dealer and pay as you go.

    good luck
     
  4. bshaw

    bshaw Karting

    Nov 3, 2003
    65
    Connecticut
    Full Name:
    Bill
    Oops - wrong list :)
    Make that F-chat sponsors.

    Bill
     
  5. 308GTS

    308GTS Formula 3

    Dec 27, 2001
    2,223
    TN
    Those appear to be 2 Valve Injected rotors. They aren't 79 or 85 308 rotors. Did someone engineer these and make them incorrect. Also some have tried to use Fiat/Alfa rotors that look very similar but are too long. I hope that you didn't get these. Please keep us posted.
     
  6. bshaw

    bshaw Karting

    Nov 3, 2003
    65
    Connecticut
    Full Name:
    Bill
    It went together with no problems, everything seemed to be in it's proper place. Both are aftermarket, rotor and cap. The jaws on my calipers are too short to get an exact reading inside the cap, but as close as I can tell they're the same.

    You can see the difference in the rotor once you look for it. In the 308rotor.jpg pic, the old rotor is on top (green) and the new rotor is on the bottom (black). The tip on the new one is significantly longer (and brighter).

    That what they're supposed to be.

    That's a good question.

    They can't be Fiat parts, I paid Ferrari prices :)
     
  7. lusso64

    lusso64 Formula 3

    Apr 12, 2004
    1,535
    Simi Valley
    Full Name:
    David
    Yikes!

    I'd get in contact with the vendor ASAP and have a nice little chat. If you supplied the vendor with exact information as to the year and model of the car, and even the serial number, then ask for a replacement set of caps and rotors.

    If your request was ambiguous in terms of model year etc, then I am not sure how this will turn out. Maybe a free replacement rotor would be nice, and them file down the tips until it matches the old one.

    Please let us know how this turns out, and if the vendor does the right thing by you. If they do do the right thing, then please let us know who it is. If they screw you, then it'd be nice to know also :)

    Dave
     
  8. Ken

    Ken F1 World Champ

    Oct 19, 2001
    16,078
    Arlington Heights IL
    Full Name:
    Kenneth
    I had that on my car. I heard the noise on startup and it would go away. Couldn't figure it out until I changed the cap and it was chewed as well as the rotor. I'm amazed the car ran well that way. I had had a Pertronix unit put in (by someone else) and they didn't seat the plate right. Another reason to do your own work huh.

    Ken
     
  9. Ricambi America

    Ricambi America F1 World Champ
    Sponsor Owner

    #9 Ricambi America, Oct 13, 2005
    Last edited by a moderator: Sep 7, 2017
    Everyone -

    I am the supplier who provided the rotors. I first learned of this problem this morning around 10:15am. The customer clicked the link on my website and ordered specifically 119396:

    http://ricambiamerica.com/product_info.php?products_id=194626

    There was no communication about the year of the car in any correspondance.

    Having said all that, it really doesn't matter. I'm working directly with the customer and his mechanic to immediately figure out what we should do. Clearly, sending another "wrong" rotor isn't going to help. With an aftermarket cap in the mix too, it's hard for me to know exactly which direction to turn. The customer has already been refunded 100% of his money.

    The blade on my rotor is 18mm long and extends 3mm. I would welcome anyone's input regarding these.
    Image Unavailable, Please Login
     
  10. gdbsti

    gdbsti Formula Junior

    Oct 10, 2004
    283
    Nor Cal
    Full Name:
    Bruce
    Hey Bill, did you compare the old and new rotors Before installing the new one?
     
  11. lusso64

    lusso64 Formula 3

    Apr 12, 2004
    1,535
    Simi Valley
    Full Name:
    David
    With hindsight, a very good question.

    To his credit Daniel has again done the right thing by the customer.

    This does leave Bill in a mess though....

    If it were me (and it isn't), I'd check the new caps for cracks, and if they're ok, polish up the contacts with a Dremel. Next, I'd swap Daniel the refund for a replacement rotor, and then use the Dremel again to grind down the new rotor and the remaining new (intact) one to the correct size for the caps as they now stand.

    I do wonder though whether this may be another one of those mysterious Ferrari anomolies where a small batch of cars were made with oddball parts due to some supply problem. I know things got better with the newer cars, but my old 1980 GT4 had dates on the tags sown into the ends of the seat belts. The rear ones were not only made by different suppliers at different times (1976 vs 1979) whereas the front ones were made by the same 2 different suppliers but at the same time (1978).

    Finally, that noise we all hear in the background is Daniel on the phone to his supplier asking very pointed questions ;)

    Dave
     
  12. bpu699

    bpu699 F1 World Champ
    Owner Silver Subscribed

    Dec 9, 2003
    16,247
    wisconsin/chicago
    Full Name:
    bo
    Kudos to Daniel! Quick, to the point response. Why can't all vendors do that?
     
  13. Ricambi America

    Ricambi America F1 World Champ
    Sponsor Owner

    Is anyone willing to pull their good, OEM rotor and take measurements? I'll send a nice Ricambi embroidered shirt to you for your trouble.
     
  14. tbakowsky

    tbakowsky F1 World Champ
    Consultant Professional Ferrari Technician

    Sep 18, 2002
    19,379
    The Cold North
    Full Name:
    Tom
    Ok I've got a brand new in the bag Marelli rotor in front of me. Measuring from your points I have 2.42mm at the smallest end and 18.01mm on the length. If I measure form the center of the spade end of the rotor to the rear of the large brass center (with the 2 screws in it) piece I get 43.28mm.
    Hope this helps..
     
  15. Ricambi America

    Ricambi America F1 World Champ
    Sponsor Owner

    Tom - Hang tight... I'm going to get my calipers and remeasure. Your 2.42 measurement is at the tip, right? The center is a little wider, correct?
     
  16. Ricambi America

    Ricambi America F1 World Champ
    Sponsor Owner

    Wow.. unless the tolerances on the rotor are supposed to be within microns of the cap, I'd say Tom an I are just about dead on. My tools are probably not as accurate as his, but I show:

    2.55mm on the tip
    18.00mm on the spread,
    44.00mm on the bottom plate

    Tom - PM me, and I'll send a shirt up north! Now, more importantly, what do you think about this subject? Is my rotor a piece of crap? Should we focus on the customer's cap instead?

    (Just trying to make things right, not assess fault or blame.)
     
  17. 308GTS

    308GTS Formula 3

    Dec 27, 2001
    2,223
    TN
    First off great customer support. Second, I would look at the cap after seeing the values. Did you sell him the cap or did it come from another supplier?
     
  18. bshaw

    bshaw Karting

    Nov 3, 2003
    65
    Connecticut
    Full Name:
    Bill

    On the original I get 0.060" (*25.4 = 1.52 mm) at the tip and 0.708 (*25.4=17.98mm) on the length. It's a little tough to measure because the corners are rounder than the new one.

    On the aftermarket I get 0.105" (*25.4 = 2.66) at the tip and 0.709" on the length.

    So it looks like we agree that 3 of the rotors are the same, but all different from the one originally in the car.

    I appreciate all the help guys, whatever the problem ends up being.

    Bill
     
  19. bshaw

    bshaw Karting

    Nov 3, 2003
    65
    Connecticut
    Full Name:
    Bill
    I agree, great customer support. The cap came from elsewhere, also aftermarket.

    I just saw Tom's post, and have the length measurements to add.

    The original is 43.56mm and the new one is 43.99 mm, but I don't think that difference is significant.

    Does anyone know how close the rotor should pass to the terminal in the cap?

    Bill
     
  20. tbakowsky

    tbakowsky F1 World Champ
    Consultant Professional Ferrari Technician

    Sep 18, 2002
    19,379
    The Cold North
    Full Name:
    Tom
    Hummm..quite interesting..amazing the differences however small. As far as the rotor gap to the terminal on the cap..I have know idea how you would measure that one. If you guys need..I can dig out my camera and post a pic of what I've got.
     
  21. tbakowsky

    tbakowsky F1 World Champ
    Consultant Professional Ferrari Technician

    Sep 18, 2002
    19,379
    The Cold North
    Full Name:
    Tom
    Yes..I think your rotor is ok. I would verifiy the cap now. From what I remember there are differance in the caps from the 2valves to the 4 valves. I'm wondering if he got a 4 valve cap? I have a 2 valve cap at work. I'll bring it home tomorrow.
     
  22. Ricambi America

    Ricambi America F1 World Champ
    Sponsor Owner

    #22 Ricambi America, Oct 14, 2005
    Last edited by a moderator: Sep 7, 2017
    Gadzooks. The cap came from elsewhere, so we'll need Bill to respond.

    Now, here's something interesting... I have bunch of caps inbound to me from a supplier in Italy who represented them as 4-valve -- but I'm starting to wonder. They are represented as 115518. For the sake of argument, Ferrari-UK lists this cap for the QV, 308i, and 328 (but not the 308GTS, 308GTB cars)

    Here's what I have inbound to me (but have not held them, nor flipped 'em over to look inside):
    Image Unavailable, Please Login
     
  23. patpong

    patpong Formula 3

    Jul 6, 2004
    2,274
    Bangkok, Thailand
    Full Name:
    Patpong Thanavisuth
    After reading through all responds, no one has mentioned the fact that there are a single distributor and twin distributors model on the 308. And the cars during same year could be either single or twin distributors. The single distributors which handle all eight plugs in one cap and the twin ones handle four plugs in each caps, so the rotor of the twin cap could be shorter than that of the single distributor.... ( my guess ). It could be that Bill recieved a longer rotor from a single distributor for his twin distributors car.....
     
  24. CliffBeer

    CliffBeer Formula 3

    Apr 3, 2005
    2,198
    Seattle, Washington
    Full Name:
    Cliff
    Incidentally, does anyone have pics or part numbers or model numbers for the Alfa/Fiat (poor) substitutes here? Would be interesting to line 'em up side by side and see the magnitude of the differences....
     
  25. Ricambi America

    Ricambi America F1 World Champ
    Sponsor Owner

    He has a twin distributor car.
     

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