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78 308GTS timing belt & Carberator question

Discussion in 'Technical Q&A' started by thevirginiadude, Apr 18, 2004.

  1. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    I have to rebuild the carbs and replace timing belts on a 1978 308GTS.

    I do not yet have a shop manual but need to quote a guy a rate for the work.

    Does the Crank pulley and harmonic balancer have to come off to replace the timing belt(s) . And any tips on the Carbs, pitfalls or things to be careful not to do.

    I saw the timing belt thread. This car has never had the Timing belts replaced in its life so far. I think he has been on borrowed time for years even though the car has just over 7,000 original miles.

    I am asking since the manual is not in my possesion yet and I have never seen a blown up diagram of the timng belt layout. And I need to quote a price for labor , he knows parts will be at cost additionally.
     
  2. pma1010

    pma1010 F1 Rookie

    Jul 21, 2002
    2,559
    Chicago
    Full Name:
    Philip
    Buy the manuals before you touch it (Spare Parts Catalog and Workshop Manual). Maranello and several other places usually have them.

    No, you do not need to pull the crank pulley to do the belts. The cam belts are not driven from the crank pulley. You should replace the tensioners.

    The carbs are likely to need a complete overhaul.

    A 30,000 mile service, including re-shimming is usually a 30 hour job at a dealer.

    You should also R&R the water pump "while he's in there".

    If the car has been neglected, there are many other parts that will need replacement and servicing too (rubber hoses, distrib advance...).

    I'd advise the owner to have a comprehensive evaluation of the car done by someone who is familiar with the marque and the model. From there, you and he can decide who tackles what.
     
  3. Steve Magnusson

    Steve Magnusson F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    19,255
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    Steve Magnusson
    You can review the 308GT4 WSM here: http://ferrari.jenkins.org/books/ (although sounds like having a hard copy makes sense for you). ditto what Philip said about having the SPC for the model you're working on -- very useful (as is the OM). Good luck with the project...
     
  4. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Well This fellow bought this car new. Does not have the money that the dealer asked for the job. He's elderly, sharp as a tack and has been a good friend for years. Being as the local dealership messed up his other car he choses not to take it there, $5,000 later and its worse than it was when it went in. Me he trusts as a mechanic.

    And no I am not taking anything appart till I have the manual.

    I am quite decent a mechanic, with specs and stuff in front of me I am confident I can handle it. I have built a few Hot rod hondas, (did the swaps and rewired harnesses to work (camshfts etc) Totaly Rebuilt a triumph GT6, worked on Mercedes diesels, GM Diesels, and a whole range of domestic cars, and Harley Davidsons. I am no stranger to a wrench and insides of a motor.

    But no this is my first Ferrari. THis has to be easier than working on a Lambourghini Countach......Nothing can be harder than that. I have worked on one.

    OH, valve clearances should not be an issue, it has only 7,250 miles, and its accurate according to the owner.

    Thanks for the link. It will let me research before I have the hardcopy manual I requested the owner purchase.
     
  5. Steve Magnusson

    Steve Magnusson F1 World Champ
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    Jan 11, 2001
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    Wow -- you are a good friend (to do a major on somebody else's mistress, I'd want 2X the highest amount a F dealer ever charged ;)). No need for a defense -- by having a "hard copy" I assumed that you were a professional now embarking on including F in your services so adding a reference copy to your business would be logical -- wasn't meant to be a slight.
     
  6. tbakowsky

    tbakowsky F1 World Champ
    Professional Ferrari Technician Consultant

    Sep 18, 2002
    15,097
    The Cold North
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    Tom
    The balencer needs to be loosened and pulled back in order to get the new timing belts on without twisting them. This job is not difficult at all. Don't be intimidated by the horsie on the hood. It's just an engine when it comes right down to it (although an expensive one!!)..

    The cam marks for are located under the cam covers. There are scribe marks in the cams which line up to scribe marks in the front cam caps.

    To correctly find top dead center, remove the triangal cover just below the oil filter. You will see a pointer. Remove all spark plugs from the engine. Rotate the engine in a clockwise direction until you seem PM1-6. You will see a line just after. This line is top dead center. With this lined up the marks on the cams should be right lined up with the marks on the cam caps.

    Once you have determmind evrything is good you can remove the old timing belts from the engine. I remove only one side at a time, I replace only one belt, rotate the engine 3 times, check everything is aligned and then do the other belt. Obviously you want to replace the tensinor bearings. Very important to lube the spring and slider befor reassembly.
     
  7. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    10,162
    San Carlos, CA
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    Mitchell Le
    Sounds like you are a very decent mechanic, even though not yet on Ferrari cars. That is OK, the 308GT4 is just another V8. With the manuals, you will figure it out. There are no really special instructions. Just that you need to check the timing twice, once for each bank. The books will tell you how.

    The carbs, are just carbs. Rebuilding them is straight forward.
     
  8. yelcab

    yelcab F1 World Champ
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    Nov 29, 2001
    10,162
    San Carlos, CA
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    Mitchell Le
    By the way, I would also second the opinion of:

    1. Rebuilding the water pump. That is straight forward if you remember that the shaft is pressed out toward the engine side of the pump. Upgrading to a larger bearing type is not necessary unless you also have to drive a smog pump off the same pulley.
    2. Do change all the rubber hoses for gas, vaccum, and coolants. They are now 25 years old.

    With all that done, and the timing belts / bearings, your friend's car could be a very nice car after that.
     
  9. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    10,162
    San Carlos, CA
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    Mitchell Le
    As for a quote:

    For the timing belts and bearings alone, the first timer (even a good mechanic like yourself) will need 16 hours. 8 to go in and 8 to come back out.

    It takes me an entire weekend, with the valve adjustment too. But, I go slow just so I can catch everything, stop and have a beer, chat with the neighbors who always come out to watch, and also pay attention to the wife and kids when they feel ignored.
     
  10. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    10,162
    San Carlos, CA
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    Mitchell Le
    Damn, always forgetting somethine.

    The valve cover gaskets are supplied in one piece, but needs to be cut and trimmed to fit. Use a minute dab of silicon grease at the point where it meets the cam shaft oil seals.

    I prefer to use Hylomar instead of the blue/red/grey silicon stuff to dress the rest of the valve cover gasket.

    Did I say you probably should change the camshaft oil seals? especially if they are leaking? If so, add 2 hours to the estimate, the shaft has to come out.

    And, you need a $74 4-slot ferrari only socket to remove that pulley on one of the shafts. Buy it from Baum tools, and it is the same as the one for the timing gear socket. I had to buy this one too, it is hard to make with a bench grinder.
     
  11. carlrose

    carlrose Formula Junior

    Nov 25, 2003
    295
    Hi Virginia-dude (?),

    Drop me an email at carlrosemd@hotmail.com. May be able to help you out with manuals.

    :) Carl
     
  12. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    I am not a mechanic by trade. But its a second line of work to fall back on.

    I do my own wrenching, have done a lot for others. Have fixed a lot of cars certified mechanics had messed up.

    Well working with the unfamilliar doesn't faze me. As long as I have a set of manuals in fron of me I can deal with most anything short of a major rebuild.

    Like I said I amazed him when I got his lambourghini running with no shop manual the first time I ever looked under the hood of one of those.

    If I get enough to be worth the time I give up I am happy. Hell I'll charge at least my overtime rate at my day job. Great for him and good for me. He asked me to look it over and tell him if I thought I could do it. I did, and think while its time consuming its not all that diffcult. THe carborators will be the most difficult part. Balancing all 4 to each other. Don't know what year they went to fuel injection but it wasn't in 1978.

    I want hard copy manuals I told the owner. who will pay for them. And will keep them with the car if I have any future need to work on it.

    Now if I can figure out the injection system of the Lambourghini I will make him a happy man and make myself A nice chunk of spare change. Local shops here are not all that good. The local Ferrari shop is who hosed up his Lambourghini. I got it running but am convinced he has injection system issues. The Ferrari dealer won't touch it.
     
  13. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    The most carbs I have previously balanced were a pair of Zenith Strombergs on a 1970 Triumph GT6+ I used to have for 10 years.

    Don't want to rip the guy off, but don't want to underbid on price and find out I have 5 times the work I was expecting either.

    I need to give him a labor price I want for the job which I explained to him he will pay me Plus all parts needed.

    This thing has no real leaks and prefer not to dig further into this than I absolutely need to. But still do it exactly as is needed, belts tensioner etc.

    two carbs leak now but I will refit all 4 so the other two don't start leaking next year.

    That front bank cover looks like a real joy to deal with. Sure didn't build these with service in mind.

    But a huge amount easier to work on than a Lambourghini. I think design engineers intentionally made that car hard to work on. Like they had a vendetta against mechanics or something.
     
  14. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Will do.............
     
  15. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    10,162
    San Carlos, CA
    Full Name:
    Mitchell Le
    Rebuilding all carbs is the right thing to do, you will need an air flow meter (Superformance in the UK sold it to me for $40). Then it will be a really easy job.

    To make the front bank easier, remove the hood, cover the trunk with 3 thick big towel, lay a piece of plywood over the engine, and lay on it to work on the front bank.
     
  16. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Great tip. I'll do that.
     
  17. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    I got the Timing Belts, And tensioner bearings replaced too, Took all of 8 hours to do total. But I am having major problems in that I can not find a way to get the damned alternator tightened down since the A/C pump has to be mounted or it hits the belt. THat means I can't get my arm in from that side, can't get it in from underneath either. Maybe with 2 feet of extensions I can get in from drivers side. Oh, this is so frustrating its not even funny.

    Any tips before I blow a gasket, have a stroke or something. I spent the past hour using search. And heading back over to garage now to see if I have a brainstorm tonight. Want to do the carberettors tomorrow. But need this finished first.
     
  18. Steve Magnusson

    Steve Magnusson F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    19,255
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    Steve Magnusson
    You mention "underneath" -- don't you have the RH rear fender liner out and rear wheel off?
     
  19. thevirginiadude

    thevirginiadude Karting

    Apr 18, 2004
    63
    Fairfax County, VA
    Yes I do, I figured out a way, the only way I could do it was lay under the engine of car, left forearm could just make it through under the Alternator from the wheelwell area, to hold a short wrench that could be pushed to tighten with a chunch of wood through the triangular hole on the frame. Forearm is too large to get even halfway to elbow. THat was a horrible PITA.

    Long story short, I got the timing belt/tensioner part of the Job finished in 9 hours.

    Tomorrow afternoon I start the Carborettors.
     

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