Mondial 3.2 high HC emission values - Advice Welcome | FerrariChat

Mondial 3.2 high HC emission values - Advice Welcome

Discussion in 'Mondial' started by caterus, Aug 23, 2024.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. caterus

    caterus Karting

    Dec 24, 2010
    68
    Oxfordshire, UK
    Full Name:
    Tim
    #1 caterus, Aug 23, 2024
    Last edited: Aug 23, 2024
    My UK 1986 Mondial 3.2 is running nicely, tickover OK, starts hot and cold without problems.
    But it has just failed an annual inspection on emissions. CO value is low well within Ferrari recommendations but HC (hydrocarbon) values are too high and about 2000 ppm (max allowed is 1200ppm).
    I've tried adjusting the Bosch K-Jet fuel mixture levels (with the special tool) but I'm unable to reduce HC levels to acceptable levels.
    Has anybody had a similar problem?
    Any suggestions on how to tackle this problem would be really appreciated.
     
  2. moysiuan

    moysiuan F1 Rookie
    Silver Subscribed

    Nov 1, 2005
    3,958
    Canada
    A few questions,

    How high was the reading?

    Has your fuel distributor ever been rebuilt?

    Does your car have the cat and O2 sensor?
     
  3. Rifledriver

    Rifledriver Three Time F1 World Champ

    Apr 29, 2004
    36,401
    Cowboy Capitol of the World
    Full Name:
    Brian Crall
    2000 is the max most machines will read so it may very well be higher than that. That is not just a little too high. It should be reading more like 200 even with no catalytic converter. With a converter it could be as low as zero. No fuel mixture adjustment is going to fix that. It is far and away beyond that. Even 1200 is very generous. I have never heard of an allowable amount that high.
     
  4. theunissenguido

    theunissenguido F1 Rookie
    Owner Silver Subscribed

    Jan 21, 2004
    2,545
    Argent/Brasil
    Full Name:
    Guido
    Before the MOT I remove the screw of the hole of the mixture screw on the fuel distributor, so extra air is sucked in. This reduces those values drastic. After the MOT I put the screw back.
     
  5. mike32

    mike32 F1 Veteran

    May 13, 2016
    5,883
    Isle of man- uk
    You can buy the fuel dist overhaul kit off e bay, there is a label on the size to show you which one you need. Injectors done recently . Also try some injector in the tank like redex
     
  6. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,226
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    What do you mean by "special tool"? A male 3mm hex (allen) key?
     
  7. caterus

    caterus Karting

    Dec 24, 2010
    68
    Oxfordshire, UK
    Full Name:
    Tim
    3.2 Euro Mondials do not have a Cat or O2 sensors
    Tim
     
  8. caterus

    caterus Karting

    Dec 24, 2010
    68
    Oxfordshire, UK
    Full Name:
    Tim
    See previous reply on HC allowable levels
     
  9. caterus

    caterus Karting

    Dec 24, 2010
    68
    Oxfordshire, UK
    Full Name:
    Tim
    I used a Sealey key set sold as 'tamper-proof hex keys suitable for K and L Jetronic fuel injection'. Perhaps it is just 3mm and 5mm hex long keys.
     
  10. caterus

    caterus Karting

    Dec 24, 2010
    68
    Oxfordshire, UK
    Full Name:
    Tim
    Thanks Mike for helpful tip.
    Tim
     
  11. mike32

    mike32 F1 Veteran

    May 13, 2016
    5,883
    Isle of man- uk
    It might just some injector cleaner, be sure to have tank with just bit of fuel in it, then a bottle of redex injector cleaner into tank. Mine mondial used to cut out on me. The disr does not take very long if you good with tools
     
  12. caterus

    caterus Karting

    Dec 24, 2010
    68
    Oxfordshire, UK
    Full Name:
    Tim
    Mike, Checked ebay but not able to find suitable distribution overall kit. I'm OK with tools. Do you have a reference?
    Tim
     
  13. mike32

    mike32 F1 Veteran

    May 13, 2016
    5,883
    Isle of man- uk
    Been a while since mondial, I will have a look for you
     
  14. mike32

    mike32 F1 Veteran

    May 13, 2016
    5,883
    Isle of man- uk
    On e bay look for a k tronic over haul kit, they are used on Volvo, Porsche etc- you need the number off the label on the side of the original
     
  15. mike32

    mike32 F1 Veteran

    May 13, 2016
    5,883
    Isle of man- uk
    List comes on google as well
     
  16. Freddie328

    Freddie328 Formula Junior

    Jul 29, 2013
    372
    Herts, UK
    Full Name:
    Richard
    This happened on mine. The vacuum valve bypass pipe had split. The one between the fuel distributor and valve.
    Its also worth checking that none of the spark plug leads have high resistance, extenders no resistance and plugs are ok, before you start taking the fuel system apart.
    Just one cylinder not firing correctly will cause HC levels to rocket.
    What was the CO reading?
     
  17. moysiuan

    moysiuan F1 Rookie
    Silver Subscribed

    Nov 1, 2005
    3,958
    Canada
    Yes, check all vacuum hoses, originals are rock hard by now. The fuel injection senses a lean mixture and dumps more fuel.

    Also make sure you have new spark plugs, and check the old ones for any sign of fouling, which will pont to your distributor cap and wires/extenders as possible culprits. These cars can run quite well with one cylinder not firing correctly. Take the rear bank plugs out which are easy to access and see how they look to start with. If all are fouled on one bank it points to a coil failure underway. If all plugs are fouled it points to the fuel distributor,
     

Share This Page