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'79 308GTS popping in Carbs and exhaust

Discussion in 'Technical Q&A' started by thevirginiadude, May 6, 2004.

  1. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Car is popping occaisoinally from carbs, and from exhaust. Found about this after Timing belt, tensioner job and rebuilding leaky carbs.

    ASked owner if it was doing this before. Said reluctantly it was, of course he tells me this after fiddling with carbs for an hour trying to get it to idle smoothly. I have trouble getting car to idle at anything under 1,000 rpm. Figure its a points and or timing issue. Think the owner did these himself but he is a bit evasive on that question.

    Does this sound like a misadjusted points issue? Before I even take that appart, and does anyone know a USA source for the Electronic ignition conversion I heard about for this. And how much does that run.
     
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  3. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    10,180
    San Carlos, CA
    Full Name:
    Mitchell Le
    Could be a bunch of things but I bet you are looking for more specific answers that that.

    1. Possible that the carbs were not rebuilt correctly, or completely. It maybe worth it to ... do it again so that you know it was done correcty. All it costs now is a set of gasket.
    2. Timing issues with distributors (points and condensors are a bit&*). At least check the dwell, gap, and the overall condition of the dizzy caps and rotors.

    For ignition systems, look for 1) electromotive, 2) Crane Cams, 3) Nick S. (sponsor of this site).

    Report back what you find, and maybe someone else will give more insights.
     
  4. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    I did carbs myself, took my time one per evening. I am certain no issues there.
    plus it was doing it before I found out, so not carbs. They were leaking fuel.

    Only 7,500 miles on them, so not worn out.

    I'll put odds its points related. Thanks I'll check that tomorrow night.
     
  5. don_xvi

    don_xvi F1 Rookie

    Nov 1, 2003
    2,920
    Outside Detroit
    Full Name:
    Don the 16th
    The plaque on my '78 says that idle speed is 1000+-200.
    And let me tell you, mine, at an indicated 500 s-u-c-k-s sucks! I can't wait to get around to raising it up!
     
  6. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    10,180
    San Carlos, CA
    Full Name:
    Mitchell Le
    'dude

    regarding the carbs, did you replace the needle valves? I assumed you got the floats adjusted spot on. Could you tell which cylider is popping? Is it always the same one?

    Ignition wires, did you replace the wires with new ones, or with ones you had to make up? What types of wires? Solid cores, wire-wound? the points where the wires go into the dizzy take some what of a trick.

    Dizzy cap and rotor: Only 7500 miles? Guess they are good.

    How about the points and condensors? got two points or one point system? New points, or old points? what do they look like on the gap surfaces? If you have time to play with the dizzy, i would take them out (assuming you have two), disassemble them carefully, clean everything, and put them back the same way (one at a time so you always have a reference). Make sure you at least check the advance so that they both match on the car.

    And, none of this is really worth much unless compression is good.
     
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  8. cavallo_nero

    cavallo_nero Formula 3

    Nov 3, 2003
    1,648
    colorado
    Full Name:
    Giovanni Pasquale
    when does it pop, my carb 308 pops whenever my foot is off the gas and i am in gear going down hill, i just live with it as i could never find the culprit. i have a direct fire ignition by electromotive by the way.
    john
     
  9. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Well , I balanced the carbs carfully again this last weekend. Major popping is not an issue but it does appear to have intermittant cylinders dropping out, mostly the rear bank. Am affraid to pull distributers apart but I know it needs points. One of the four points sets were burned real bad. trying to understand procedure for setting point timing gap is the easy part.

    Rear plugs are black................and 2-4 in front bank look normal but #1 in front appears to be almost as black as the rears.

    I am 110% certain its an ignition problem at this point.

    need to price the new points, and electronic conversions......Present that to the owner tomorrow.
     
  10. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Plug Wires were replaced by owner about a year ago with ferrari items......Not home made ones. Its a dual point system, not the single points, one of the points in the rear dizzy had burned, filed down the welded lump and regapped. never disturbed the point timing doing this. THe points are a few years old. But I do question the timing.........Some people who had worked on this car in the past really had no idea what they were doing. Yes it needs points and condensors.....need to source out electronic ignition conversion since what little I have seen on this board seems like thats the way to go , assuming I can sell the owner on the idea and if its cheap enough.

    Really hesitant to do that because the manual is not real clear how one sets the points and timing on the car without a test jig and or degree wheel.
    In fact I will do a search on that subject and if I don't find my answer I will post a new thread to ask it.
     
  11. Spasso

    Spasso F1 World Champ
    Silver Subscribed

    Feb 16, 2003
    14,612
    Land of Slugs & Moss
    Full Name:
    Han Solo
    For the same price as 4 sets of points or two distributor caps you can convert the car over to twin Crane XR700 solid state ignition boxes with optical pickups in each distributor. You can retain the stock caps, rotors and coils if you chose. If the owner is worried about appearance you can mount the boxes in a less conspicuous place and none would be the wiser.

    Once you set the basic timing with the red indicator lights on each box you can forget about periodic adjustments and burned points. It all works all the same, all the time.

    I ran my car on the dyno a couple of months ago and pulled all the way up to 8,000 RPM once without skipping a beat.

    P.S. I am running 8mm Taylor SpiroPro wires on my car and they perform every bit as good as OEM if not better for less than half the cost.

    DJ
     
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  13. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    The owners concern is more price than looks. My concern is how I can properly set up the points and have it run right. Keep in mind I have never done this on a Ferrari before. THis thing has a real rough idle, and feels way down on power. I have never driven one of these that runs right so I have no baseline. But I know it has to be way better than it is now. Let me look up the prices on stuff so I can present them to him tonight.
     
  14. pma1010

    pma1010 F1 Rookie

    Jul 21, 2002
    2,559
    Chicago
    Full Name:
    Philip
    If you are going to look at points et al, check the distrib advance curve. If it is not advancing as it should, power will be way down. If you need to send out to re-curve distrib, I'd guess it would run $100 - 200.

    I second the vote to go to an optical set up. Giovanni at Autosprint in Chicago does them all the time on 8s and 12s and swears by them. Cheaper than the Electromotive set up (which I use on my car).
     
  15. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Oh, power is way down......its a dog in fact.

    My hotrod honda will eat it alive and thats a sad thing. Since its only a 1.6L with close to 200hp. And I know that isn't right. Its hard to get this 308 moving without stalling it. No power no torque.

    My timing light is dead, need a new one so I can check timing and advance.

    This car had a lost of things wrong with it. Carbs were leaking and timing belts were still the original ones when the motor was built in 1978.

    Thats fixed now but I knew from the rough running it had ignition issues too. The Speedo has stopped working in the last week and the water Temp guage has also. THis guy had better cough up more money if he wants all this stuff fixed. I don't work for free.
     
  16. BigTex

    BigTex Seven Time F1 World Champ
    Rossa Subscribed Owner

    Dec 6, 2002
    73,162
    Houston, Texas
    Full Name:
    Bubba
    Maybe just to calibrate, for that price. They'll find worn bushings and springs.

    T Rutland's REBUILT both of mine for $500 each, and I thought I was going to have to drive over to the door to get them back! HTH.

    NOS at FoA for $800 each, last time I checked. Might be the way to go, actually.
     
  17. BigTex

    BigTex Seven Time F1 World Champ
    Rossa Subscribed Owner

    Dec 6, 2002
    73,162
    Houston, Texas
    Full Name:
    Bubba
    Good luck. There are folks here that will talk you thru it. It's not rocket science, but by the time these tough cars fall over dead, you are trouble shooting an array of problems.
     
  18. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA

    OW! this guy is NOT going to be happy with that.

    He really want this running right so he can sell it along with his Countach so he can buy a Testarosa.
     
  19. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA

    I agree. This seems to think I will fix his ignition problems for no extra charge just because he paid me to rebuild carbs (they were leaking gas) and replace timing belts (they were 26 years old).

    $1,000 labor I got for that job doesn't begin to cover my time for all the other problems this car has.
     
  20. BigTex

    BigTex Seven Time F1 World Champ
    Rossa Subscribed Owner

    Dec 6, 2002
    73,162
    Houston, Texas
    Full Name:
    Bubba
    If he's dumping it, just do the best you can degreeing the timing and cleaning lubing the points, caps, distributors, calibrating them if a machine is available.
    The engine sounds like it's out of time to me.

    '79's are way down on power due to the cam profiles anyway.
    What color, miles? Put it on FerrariAds as a "project car'.

    Original belts! Hah!
    Sounds like a typical "deferred maintenance owner" to me. Drive it to the ground, and dump it on an unsuspecting newbie!
     
  21. BigTex

    BigTex Seven Time F1 World Champ
    Rossa Subscribed Owner

    Dec 6, 2002
    73,162
    Houston, Texas
    Full Name:
    Bubba
    LOL! My tech charges his shop rate when he's THINKING about my broken speedo!!

    Look at the bright side! The odo quit at the same time :)
     
  22. BigTex

    BigTex Seven Time F1 World Champ
    Rossa Subscribed Owner

    Dec 6, 2002
    73,162
    Houston, Texas
    Full Name:
    Bubba
    $1,600. for carb rebuild, belt service around $400 - $600 IIRC.

    Then the distrib rebuild I mentioned.

    This is a strange thing some folks refer to as "proper vehicle maintenance", on a twenty five (in my case) year old vehicle.

    Seen any '79 Vegas, lately??? LOL!

    I drove mine to work today and you could hear that blown out ANSA for six blocks!! Forza, dude.
     
  23. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Well it only has just over 7,000 miles on it. ANd I know last time I drove it the speedo wasn't working, but the time before that it was.

    Well the car needs some TLC.........but it has no rust. And yes you are right about deffered maintenance.

    It never had the 30,000 mile major done.....and its way overdue just on time.

    Its a 1978 308GTS, silver with Red interior. And has had all the Smog gear removed at some point in the past.
     
  24. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Well he got carbs rebuilt and timing belts replaced along with the tensioner bearings for $1,680 which was $1,000 labor and the rest in parts.

    He just wanted me to do the Carbs........I noticed it had timing belts and asked him when they were done last, he looked at me like "are they supposed to be replaced". Said yes.....21 years ago for the first time.and should have been done 4-5 times based just on age.
     
  25. BigTex

    BigTex Seven Time F1 World Champ
    Rossa Subscribed Owner

    Dec 6, 2002
    73,162
    Houston, Texas
    Full Name:
    Bubba
    Tensioner bearings also!!

    I'm on the floor laughing, because the cars come with BOOKS and TOOLS.

    You read the BOOKS late at night, instead of boinking Buffy, and you use the TOOLS to perform the recommended maintenance, per a strict mileage/or age schedule, as you have mentioned.

    Good luck with this guy, he sounds rich, but not too smart.
    A Ferrari owner unaware of the "Great Timing Belt Debate"?? I'm amazed.
    I ran a '77 308GTB with twelve year old belts (That was 1200 miles ago on this car) 2,245 miles last weekend at speeds of 100MPH thru the NV, AZ, NM
    TX region, but Mario Andretti personally blessed it, first! We had a little vino, as well.

    I still get around to Buffy, often enough!!
     
  26. BigTex

    BigTex Seven Time F1 World Champ
    Rossa Subscribed Owner

    Dec 6, 2002
    73,162
    Houston, Texas
    Full Name:
    Bubba
    You sound like a really fair shop, cost wise.

    IF the belts were original and the cams are still correctly oriented, I'd wager your problem lies in distributor advance. It's mechanical, and you can imagine the power drop if one bank sticks at "idle". The other bank is pulling the motor every step of the way.

    Speedo/sender failure is notorious on these cars. There is actually a page in the Owner's Manual (There's that BOOK again!) where you record the mileage when you replace the first one with a new one! Enzo thought of EVERYTHING! LOL!
     
  27. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    I set the engine to tdc and put it in 1st with ebrake set. painted reference marks on everthing, swapped belts and everything went right together adn marks remained perfect. Well I know what you mean about scheduled maintenance........but 26 years on factory belts....thats pushing your luck. I wouldn't take a chance with a honda half that age. And certainly not with a Ferrari. Yeah they may have lasted a few more years, or they might have snapped next time it was started.

    I'm not really a shop. I do this as a side business for extra money. I'm in Telecomunications as a day job. Probibly should reconsider making this a day job......heaven knows now is not a good time to be in Telecom, but as long as there are cars someone wil be needed to fix them. I have a great rep for being honest with people and aking pride in doing a good job.
     
  28. BigTex

    BigTex Seven Time F1 World Champ
    Rossa Subscribed Owner

    Dec 6, 2002
    73,162
    Houston, Texas
    Full Name:
    Bubba
    Right on. If you ever decide to pull the plug, Pinnacle Motorsports in Houston maintains my car. ALWAYS looking for folks who can "get it done right".
     

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