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So why change your points

Discussion in ''How To' & 'Handy Hints'' started by ttmck, Apr 22, 2007.

  1. ttmck

    ttmck Super Moderator Staff Member

    Messages:
    2,733
    Location:
    Hallett Cove STH AUS
    Do you know when a mechanic says 'Hey changed your points '"she'l b right now mate " What the hell is talking about , what do they look like ? What they actually do in an engine i hope to answer some of these questions in simple terms .

    A picture of the distributor points
    [​IMG]

    So now you know where they are located inside the distributor what the hell do they do , ok up off your chair go to the nearest light switch turn it on
    yep the light comes on , now turn it off , this action you have just done by switching the light switch on is exactly what the distributor points do in an engine [they are a switch]

    In order to to understand i will give you a very basic introduction to the ignition system and why points perform such a vital function .

    A typical circuit of an ignition system and how it works
    [​IMG]
    A battery , an ignition switch is located in the circuit
    As we all know most vehicle run 12 volts and the ignition system is made up of two voltages a low voltage and a high voltage some times known as primary and secondary .
    The low voltage is 12 v the high is 20000v + how does 12v become 20000 v
    well the answer is simple a magnetic field is produce and amplified inside the ignition coil
    The ignition points inside the distributor switch this voltage on and off but very rapidly the shaft under the rotor button turns as the engine spins over
    the special shaft which locates the rotor button is square shaped it has high points and low points . as the rubbing block of the points makes contact with the shaft the high points open and the low points make the contacts shut . [​IMG]
    Hence this action is a switching action like you getting up to switch the lounge room light on .
    The path of voltage then comes out of the coil via the centre lead to the distributor cap where all the spark plug leads are in a special order ,attached to the distributor cap the rotor arm attached to the centre shaft spins also . sending the spark thru the cap then to leads , eventually working its way to the spark plug , the spark jumps across the plug gap igniting the fuel , hence we have lift off !
    The main items that wear is the actual gap [​IMG]
    The brown rubbing block that contacts the centre shaft , this must be lubed with grease every time the points are changed , also a few drops of oil when the rotor arm is taken out .
    Once the points are changed the timing must be checked .
    but i the reason to why i have written this is too let people know what they do and why they are so important in a tune up . i hope that i have hodoo'd out of what function they do in simple langauge cheers tom

    sorry i had to delete two images i could not post pics of an igntion coil or the distributor
     
    Last edited: Apr 22, 2007
  2. ttmck

    ttmck Super Moderator Staff Member

    Messages:
    2,733
    Location:
    Hallett Cove STH AUS
    The distributor
    [​IMG]


    The ignition coil
    [​IMG]
     
  3. ttmck

    ttmck Super Moderator Staff Member

    Messages:
    2,733
    Location:
    Hallett Cove STH AUS
    was havin a wee tidy up in this section look what i dug up have you seen for all those people who still have points
     
  4. jon ward

    jon ward Active Member

    Messages:
    5,759
    Location:
    Travelling Australia
    Very good description! All in nice easy laymans language that even a tyre fitter like me can understand!
     
  5. dbs

    dbs Member

    Messages:
    949
    Location:
    Melbourne
    now that you know what points are, have a new set in your glove box... if you find that your driving along the highway and suddenly lose all power... plenty of fuel... battery is ok... engine turns over... check your points closely, chances are that the brown rubbing block has broken and folded over. This means no solid spark getting to the cylinder to ignite the fuel and give you power.

    grab your spare set, swap them over, adjust the gap. and you're good to go.

    yes this has happened to me and yes I did have a new set in the glove box.
    ;)
     
  6. Syncro27

    Syncro27 Well-Known Member

    Messages:
    5,833
    Location:
    Terrigal, NSW Central Coast
    Where do you get the points from?

    Most parts places have no idea about kombis older than T3's and even then it is the late model T3's that they actually stock.

    Any particular outlet you could recommend?

    Thanks for any help.

    Cheers,

    Scott
     
  7. dbs

    dbs Member

    Messages:
    949
    Location:
    Melbourne
    take a sample in, they are bosch so they should be able to match them or order them in... The newer bosch catalogue doesn't list them, but a good auto parts store will have a copy of an older catalogue which does list them.

    Or try you friendly bavarian parts supplier such as... http://www.hsy.com.au/html/master.html

    Or you can order them from the states...
    http://www.autosportvolkswagenparts.com/
     
  8. GypsyWannabe

    GypsyWannabe Active Member

    Messages:
    3,032
    Location:
    Quakers Hill, Sydney
    Bosch 534 is what you're looking for.

    Baz
     
  9. kombibob

    kombibob New Member

    Messages:
    230
    Location:
    \
    This same thing happened to pat only yesterday.
     
  10. phatratpat

    phatratpat New Member

    Messages:
    1,863
    I didnt have a spare,so had to walk 20min to supacheap....oh the chaffing
    think I need a skin graft !!......lesson learnt will be buying a back up set
    tomorrow !!!
    who said you cant get 18months outa a set of points !!!
     
  11. dbs

    dbs Member

    Messages:
    949
    Location:
    Melbourne
    :lol:
    I feel for you, when it happened to me it took I while in the dark with a torch to find the problem because the rubbing block didn't break clean off,... it kind of hinged,... so it looked fine when it was in the closed position.
    an hour before I realised...
    ;)
     
  12. phatratpat

    phatratpat New Member

    Messages:
    1,863
    so did mine ! wasnt till I had pumped some fuel over the hot exhast then rang bob
    he told me to check point gap,I reset the points then hand cranked the donk,still no
    movement...then I had a long hard look at the points!!!
    still any breakdown you can drive away from is a learning experience!!
    by the way what is the rubbing block made out of?.....anyone ....?
     
  13. nikferatu

    nikferatu Active Member

    Messages:
    1,456
    Location:
    Bracken Ridge, Brisbane
    Probably nylon I would guess... I read somewhere to put a bit of grease around the spindle where the block comes in contact - which I always do and I've never broken one.
     
  14. emby

    emby Active Member

    Messages:
    2,006
    Location:
    Wights Mountain, QLD
    It must be somehting to do with the time of year. Same thing happened to me aerlier this month. Rubbing block snapped and wasn't noticeable at first. My mechanic said the rubbing block was made from bakelite. Not sure if that's true or not, but you'd think they'd come up with a bit a stronger material by now.
     
  15. syncro

    syncro Well-Known Member

    Messages:
    8,957
    Location:
    Southern Highlands
    Bosch always used to be bakerlite, but I don't know if it still is. They also never used to break. Other brands would not last long with the nylon follower.
     
    Last edited: Jan 30, 2009
  16. dan_b

    dan_b Member

    Messages:
    570
    Location:
    mackay-
    and this happend to me 2day in the out back. 350km from alice or 550km from cober peady, and yes i had a spare but the 1st 1's were changed only 1 month ago.
    it wasnt broken off 100% so it took a while and had to wait for the engine to cool so i dindt fry my self but all is ok, set to 0.04 i think
     
  17. dbs

    dbs Member

    Messages:
    949
    Location:
    Melbourne
    Out there Dan I think I'd be keeping 2 spares,... running 2 batteries,... spare cap, rotor, leads, fule line, clamps and filter.
    maybe just tow a trailer with a spare kombi
    :lol:
    ;)
     
  18. dan_b

    dan_b Member

    Messages:
    570
    Location:
    mackay-
    yes well read my next post,gers kinda hairy
     
  19. geoff62sw

    geoff62sw Member

    Messages:
    769
    Location:
    sydney
    A good thread every one should read this one.


    Yes I rekon its Bakelite too.......
    Here's a speel on Phenol-formaldehyde resin's that u can file in the Useful/info file.

    Trade name "Bakelite"

    phenol-formaldehyde resin, also called phenolic resin, Phenol-formaldehyde resins are heat-resistant and waterproof, though somewhat brittle. They are … [Credit: Encyclopædia Britannica, Inc.]any of a number of synthetic resins made by reacting phenol (an aromatic alcohol derived from benzene) with formaldehyde (a reactive gas derived from methane). Phenol-formaldehyde resins were the first completely synthetic polymers to be commercialized. In the first decades of the 20th century, Bakelite, a trademarked phenolic plastic, revolutionized the market for molded and laminated parts for use in electrical equipment.
     
    Last edited: Mar 21, 2011
  20. Alpal

    Alpal Moderator Staff Member

    Messages:
    8,291
    Location:
    Melbourne Bend of Islands
    I changed mine to electronic. Cost $45. Easy to fit. Never adjust again!!
     

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