Bosch K-Jetronic (CIS) explained | FerrariChat

Bosch K-Jetronic (CIS) explained

Discussion in 'Mondial' started by Bell Bloke, Mar 27, 2014.

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  1. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
    I need a voice over artist!
    I love the narrators calmness and reassuring voice. It's the kind of voice that could say
    'Ladies and Gentlemen are port engine is on fire, but a stewardess will be round to serve tea momentaraly.' and I'd be calm
    Anyway the quality is well......but the info is simple to understand if you take it stage by stage in your head.
    I'm swatting up as I have just purchased a zine plating kit to do the injectors pipesand other stuff with.

    Have Fun! :)

    [ame=http://www.youtube.com/watch?v=a4fJAfXYxWk]Bosch K-Jetronic (CIS) explained - YouTube[/ame]
     
  2. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
    I need a voice over artist!
    I love the narrators calmness and reassuring voice. It's the kind of voice that could say
    'Ladies and Gentlemen are port engine is on fire, but a stewardess will be round to serve tea momentaraly.' and I'd be calm
    Anyway the quality is well......but the info is simple to understand if you take it stage by stage in your head.
    I'm swatting up as I have just purchased a zine plating kit to do the injectors pipesand other stuff with.

    Have Fun! :)

    [ame=http://www.youtube.com/watch?v=a4fJAfXYxWk]Bosch K-Jetronic (CIS) explained - YouTube[/ame]
     
  3. andyww

    andyww F1 Rookie

    Feb 7, 2011
    2,775
    London
    If you need to replace any of the black nylon injector lines I have plenty of spare which I am unlikely to ever need.

    Which reminds me I still have Iains "Verell" fitting tool for these lines, must get it returned!
     
  4. finnerty

    finnerty F1 World Champ

    May 18, 2004
    10,406
    Is that fitting / installation tool available anywhere ? (been looking for one for a while)
     
  5. andyww

    andyww F1 Rookie

    Feb 7, 2011
    2,775
    London
    Yes from Verell:

    Unobtainium Supply Co. - HOME

    Its a great tool, really works well. Although he recommends using 3mm bore tubing for the injector lines I decided to use the same as original, 2mm bore and the tool still works for this but the end of the tube needs to be warmed up with a hot air gun before pushing the barbed end with the tool.

    These black tubes are actually quite tough and the originals have a relatively thick 2mm wall and I dont think they really need to be replaced unless they have kinks or scuffs etc. The tubes to/from the WUR have a thinner wall as they are a 3mm bore.
     
  6. MvT

    MvT F1 Rookie

    May 25, 2013
    4,261
    The Netherlands - NH
    Full Name:
    Tijn
    Cool! I have it only on paper.
    Bought a repair kit for my Bosch Fuel Distributor 3 days ago for 70 USD (50 euro). Yes, I will get my hands on it sooner or later ;)
     
  7. andyww

    andyww F1 Rookie

    Feb 7, 2011
    2,775
    London
    I cant help thinking of the spoof science series "Look Around You". They got the deadpan narration off to a tee:

    https://www.youtube.com/watch?v=aMEPnKYX5C0
     
  8. PV Dirk

    PV Dirk F1 Veteran

    Jul 26, 2009
    5,401
    Ahwatukee, AZ
    What a great piece that combines great flashback video with my current life and times of 80's Ferrari ownership.

    I've read the Probst book twice. To me it shows the primitive brilliance of the early engineers of FI systems.

    And after owning and working on these for a few years it means so much more. I'd told someone the other day that the accumulator helps soften the pulses of the fuel pump and was relieved to see that I wasn't wrong according to the video.
     
  9. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
    Yes I've done that Heavy Metal experiment a couple of times at home, never thought to look outside for the scissors though.
    Many thanks Andy for your kind offer.I think my pipes are fine, I'm just going to remove them from the fuel distributer, clean them up and electroplate them which is a cold process as you know.
     
  10. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
  11. Todd308TR

    Todd308TR F1 World Champ

    Nov 25, 2010
    11,074
    LA
    Full Name:
    Todd
    Thanks for posting that, so glad I'm converting to modern FI.
     
  12. Brian A

    Brian A F1 Rookie

    Dec 21, 2012
    3,146
    SanFrancisco BayArea
    Full Name:
    1983 US 308 GTS QV
    Another Bell Bloke classic. Excellent information. Thank you.

    A few months ago, I purchased Charles Probst's epic, "Bosch Fuel Injection and Engine Management: How to Understand, Service and Modify". A real page turner. I was so enthusiastic, I recommended it to my wife's monthly Ladies Book Club, but they did not seize the opportunity.

    Now that I know how it works (err, generally speaking), I find K-Jet's simplicity kinda reassuring. I like it now compared to those complicated new-fangled eelektronik systems.
     
  13. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
    Ha ha, Brian, the first time I watched it I thought what a load of old bosch, but then I had a couple stiff ones with a Castrol RS chaser and slept on it. That night I had a dream, and when I woke up......I still didn't understand it.
    However last week Emily asked me how my fuel injection actually works in a practical sense. Since she is rebuilding her X19 carb at the moment I thought I'd better man up and watch that video again.
    'I now have seen the light!'
    I understand it fully.....I think. :)
     
  14. andyww

    andyww F1 Rookie

    Feb 7, 2011
    2,775
    London
    #14 andyww, Mar 28, 2014
    Last edited by a moderator: Sep 7, 2017
  15. Brian A

    Brian A F1 Rookie

    Dec 21, 2012
    3,146
    SanFrancisco BayArea
    Full Name:
    1983 US 308 GTS QV
    If you powder coat it red, it will work better.
     
  16. PV Dirk

    PV Dirk F1 Veteran

    Jul 26, 2009
    5,401
    Ahwatukee, AZ
    I've done that repeatedly but my scissors never look like that. Maybe it's the construction of my house, either in shape or material?
     
  17. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
    Is your pyramid made of tin or zinc?
    Pyramid construction material is also critical+everything must be deionised first within the immediate conductive range.
     
  18. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
    Come on Andy, build thread, build thread, build thread!!


    Picture is archived and stored.
     
  19. bartzagato

    bartzagato Formula Junior

    Aug 7, 2010
    614
    Belgium
    Full Name:
    Bart
    #19 bartzagato, Mar 28, 2014
    Last edited by a moderator: Sep 7, 2017
  20. andyww

    andyww F1 Rookie

    Feb 7, 2011
    2,775
    London
    OK here is my thread:

    Step 1: Take it all apart
    Step 2: Clean the parts
    Step 3: Put it back together
    Step 4: Check you dont have too many parts left over.

    Is this enough or more detail required?
    :)
     
  21. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
    Yep, right got it!











    .....err what was step 3 again?
     
  22. finnerty

    finnerty F1 World Champ

    May 18, 2004
    10,406
    I've considered trying to overhaul a WR as well. I am curious, since you are ahead of me with your project there.....was it even possible to complete Step 3 ?? :)
     
  23. andyww

    andyww F1 Rookie

    Feb 7, 2011
    2,775
    London
    I did this a while ago and unfortunately only have that one picture.

    The problem I had with it was the control pressure was fluctuating all over the place. This turned out to be caused by the diaphragm valve sticking owing to some crud on the small plunger (the round part slightly above and to the left of the 4 screws in the picture).

    Note this is a Euro WUR. USA cars are different (as usual!).
    The bi-metallic strip has a contact attached to it. This cuts in/out part of the heater element, so that there is a high amount of heating while initially warming up, then a lower amount of continuous heating once warm. I have not seen this feature mentioned in any CIS write-up or the Probst book.

    Things to be careful of:

    When removing the base be careful not to tear the green rubber membrane which is sandwiched between the base and body.

    When removing the contact/bimetallic strip assembly note how far down the threads on the mounting pillar it is located. If it ends up being re-assembled higher or lower the control pressure will be wrong.

    The round diaphragm is a piece of stainless-steel foil and is very delicate. Great care needed.

    Dont attempt this unless you have confirmed by using a CIS gauge set that the control pressure has a problem. Also before diving in unnecessarily, make sure the contacts on the connector on the top of the unit are clean, as a bad contact here would cause the control pressure to be wrong and the engine to run rich.
     
  24. FasterIsBetter

    FasterIsBetter F1 Veteran

    Jul 22, 2004
    5,855
    NoNJ/Jupiter FL
    Full Name:
    Steve W.
    I tried that once but with a metal cone instead of a pyramid. I ended up getting an oil derrick rather than a pair of scissors. Profits from oil production were great, until it faded away and I had to pay taxes on it. Oh well.
     
  25. Bell Bloke

    Bell Bloke Formula 3

    Dec 6, 2012
    1,839
    UK
    Ha ha ha love it! :)
     

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