+ Reply to Thread
Results 1 to 18 of 18

Hybrid View

  1. #1
    JB007
    Guest
    Location
    , ,
    Member No: JB007's Avatar


    Yes | No

    belts for 850ciA (Brit needs help please)

    Hi. I need to change my drive belts as they havent been changed in a long time and show signs of cracking.

    I have searched the archives.

    I would like to have a picture of how the belts go around the water pump aircon pulley etc..

    I am a little confused as to whether or not there are two alternators for the V12. I can definitely see one big usual looking one to the right of the engine bay as you open the hood. Is the other alternator much smaller and to the left of the engine bay?

    I have fitted auxillary belts before in other cars but this one looks a little more complicated. I understand that once you know it takes around 10 mins. It helps if you take the fan off first and thats OK with me- I am just worried about which nut I have to undo first. I can see the tensioner which looks like a shock absorber. Can I change the belts from above or do I need to jack the car up and go fvrom the bottom?

    The 2 belts are 6pk x 1080 and 5pk x 1165 ribbed as I understand.
    thanks in advance

  2. #2
    Registered Member
    Location
    Tustin, CA, United States
    Member No: 106729 el-rojo is an unknown quantity at this point el-rojo's Avatar
    Join Date
    May 2004
    Posts
    387
    Rep Power
    0


    Yes | No

    Re: belts for 850ciA (Brit needs help please)


    I hope this helps



    M70

    1991 BMW 850i 6Speed
    1997 BMW 850Ci
    1997 BMW 318ti
    1999 Jeep Cherokee Sport
    1974 Opel Manta Luxus


    Some days it's just not worth chewing through the restraints

  3. #3
    JB007
    Guest
    Location
    , ,
    Member No: JB007's Avatar


    Yes | No

    thanks but..

    I have this pic-although it looks nice but is still a little unclear.
    I cant see the alternator.

    Does the M70 have 2 alternators? How can I tell if my tensioners are no good? How do I check my pulleys? Am I looking for any play when I take the belts off?

    which nut (top or bottom) do I undo on the tensioner?

    A diagram and a dummys guide would be helpful.

    thanks Laszlo and el rojo.

  4. #4
    Registered Member
    Location
    Dallas, TX, United States
    Member No: 167182 TxGR8White is an unknown quantity at this point TxGR8White's Avatar
    Join Date
    Aug 2008
    Posts
    925
    Rep Power
    0


    Yes | No

    Try this-----> (hope the link works)



  5. #5
    JB007
    Guest
    Location
    , ,
    Member No: JB007's Avatar


    Yes | No

    exactly what I was looking for! .............

    Thanks very much TxGr8White but what is this BS about a second alternator?

    I will buy the belts tomorrow and attempt to change the belts at the Bank Holiday weekend ( Extra Monday off as is a public holiday).


    Any ideas as to check the tensioners and pulleys to see if they need replacing- I am on 100K miles.

    Finally ,(if we just consider the lower tensioner) which nut do I undo? I think its the middle one and the one on the right on the pivot is the one to adjust the tension so no need for a prybar-am I right?


    once again thank you all and I hope to let you know soooooon.

  6. #6
    Registered Member
    Location
    Mexico, MO, United States
    Member No: 89637 mlweaver is an unknown quantity at this point mlweaver's Avatar
    Join Date
    Oct 2003
    Posts
    1,276
    Rep Power
    0


    Yes | No

    some answers

    There is only one alternator. The other items driven by belts are the pentosin pump, the water pump, and the A/C compressor.

    Definately change the tensioners (in my opinion).

    You are correct about the "nuts" on the tensioner arms - one provides a pivot so that you don't need a pry bar - the other locks the arm in position.

    I found the job easier from below, so plan on removing the splash guard and jacking up the front.

    Good luck.
    Mark W in mid-MO
    2008 335xi coupe
    1993 850Ci 6-speed

    2 turbos ..................or 12 cylinders, no waiting!

  7. #7
    Registered Member
    Location
    , SC, United States
    Member No: 56726 lezonebay is an unknown quantity at this point lezonebay's Avatar
    Join Date
    Nov 2002
    Posts
    4,504
    Rep Power
    0


    Yes | No

    if car has more then 40-50k miles since the

    belt/tensioner have been changed, order the tensioners too. They will not hold up the new belt. I changed the belts at 50k+ miles and the tensioner was so good I had to cut the belt off.
    I installed new belts and they would not fit, they were way too loose. Long story short the tensioner was gone... they are not expensive and a good insurance against belt failure.

    The pulley's are also weak, plastic ones are cracking over time and causing the belt to disintegrate.

    Contact Phoenix motorsport for a alloy pulley set - a bit on the bling side (they are flashy colors or silver) but as all items GerryUK makes, they seem very good quality.

    The only downside to the metal/alloy pulley's that they are supposed to be louder then plastic. I never measured the noise but I read once that it can cause a little extra noise.


    while you are there, change the hoses as well. They age and they start to go bad from the inside so by the time you see any imperfection its too late.

    not trying to suck you into a "while you are at it change the ... " game but these are inexpensive maintenance items which will fail anyway sooner or later. I like to change and fix things when they are still good and easy to just change an item instead of waiting when they fail and pay for a lot more then just a part (towing, rentacar, etc)



    1997 BMW 840CiA
    1990 BMW Z1
    2002 Astro Van AWD
    2003 Nissan 350Z Enthusiast Package
    1987 BMW 535i with 5spd manual
    1992 BMW 735iL
    2007 Mazda CX9 AWD
    1998 Yamaha Blaster+Breeze

    1995 850CSI CD00177 (SOLD)

  8. #8
    Registered Member
    Location
    AYR, , Australia
    Member No: 135692 kennyg54 is an unknown quantity at this point kennyg54's Avatar
    Join Date
    Jan 2006
    Posts
    96
    Rep Power
    0


    Yes | No

    Re: if car has more then 40-50k miles since the

    I need to change belts and hoses on my Dakar M70 as at 90,000km I have never done so. Can you tell the address to email Phoenix Motorsport regarding the alloy pulleys ? Thanks :).........Ken

+ Reply to Thread


Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

     

Bookmarks

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
1e2 Forum