308/328/Mondial Timing belt replacement tutorial | Page 2 | FerrariChat

308/328/Mondial Timing belt replacement tutorial

Discussion in '308/328' started by Birdman, Jan 13, 2009.

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

  1. Owens84QV

    Owens84QV F1 Rookie

    Oct 2, 2001
    4,485
    Somewhere in NC
    Full Name:
    Greg
    #26 Owens84QV, Jan 15, 2009
    Last edited: Jan 15, 2009
    This is correct. There is an index mark on the cam itself and then a pair of indexes ("goal posts") on the cylinder head, inside the cam covers. As discussed above, the potentially time consuming part of this procedure is getting both forward and rear intake & exhaust cams aligned where the cam indexes are all inside the goal posts as centered as possible.
     
  2. Glassman

    Glassman F1 World Champ
    Rossa Subscribed Silver Subscribed

    Can you elaborate on these "Goal Posts", maybe a picture would be helpful.
     
  3. Owens84QV

    Owens84QV F1 Rookie

    Oct 2, 2001
    4,485
    Somewhere in NC
    Full Name:
    Greg
    #28 Owens84QV, Jan 15, 2009
    Last edited by a moderator: Sep 7, 2017
    OK...it's been a few years since I replaced my belts, so my description was a little off. I mentioned a pair of goal posts when in reality, the "goal posts" represent the leading / trailing edges of the cam timing index on the cylinder head. In the attached pic (not mine) from a different thread, the lower cam timing mark (bottom arrow) on the cam should be within the wider cam index mark on the cylinder head. Ignore the large marker mark on the cam...that does not seem to be factory original! Sorry for the confusion.
    Image Unavailable, Please Login
     
  4. climb

    climb F1 Rookie

    Sep 19, 2006
    4,866
    Atlantic Beach Fl
    Full Name:
    Stuart K. Hicks
    #29 climb, Jan 15, 2009
    Last edited: Jan 15, 2009
    Why do you put marks on the old belts if your just going to take them off?

    Why do you mark the new belts and how do you make the marks on the new belts line up with the marks on the cam gears?

    As long as the cams are locked why do you need to make reference marks. Can't you just slide them on anyway they'll go and adjust the tensioner?
     
  5. Artvonne

    Artvonne F1 Veteran

    Oct 29, 2004
    5,379
    NWA
    Full Name:
    Paul
    You mark the old belt so you can transfer marks to the new one. You put them on the new one so you can maintain the same timing previous. The cam and belt have "teeth" and the teeth are what maintain continuous position.

    If you dont maintain the marks, you will have no reference guide to follow, you wont have any way of knowing if your timing remained correct or not. One tooth off is quite a ways if you miss it.
     
  6. climb

    climb F1 Rookie

    Sep 19, 2006
    4,866
    Atlantic Beach Fl
    Full Name:
    Stuart K. Hicks
    Thanks

    So you mark the old ones and take them off hold them up to the new ones and put the same marks in the same locations on the new ones.
     
  7. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    The marks on the belts are just a sanity check. Like the procedure says, you put marks on the old belts that match marks on the cam pulleys. Now you transfer those marks to the new belts from the old belts. When you mount up the new belts, everything should match the marks on the pulleys. If not, something is wrong. It just keeps you from moving the timing by a tooth. Admittedly, with everything locked, it would be pretty hard to do that, but it really adds very little time to the procedure to do this step, and it could save you a lot of hassle and gives good peace of mind.

    Just washers to align the AC compressor's pulley with the balancer pulley so the AC belt isn't crooked.

    You don't need one, but there is a spec in the manual for the torque on that fastener, so why not use it? If you don't own a torque wrench, GET ONE! Very useful tool that all Ferrari wrenchers should have in their toolbox. How can you properly torque your lugbolts without one?

    When you loosen the nut holding down the tensioner bearing, the belt tension will push the tensioner back a bit, but yes, it is fine to use a gentle pry bar to push it back more. I think I need to change something in my text, because now that I think about it, what I do is push the tensioner back with a pry bar, slip the belt off, THEN wrestle the tensioner off its mount. Other option like you said is to pry it back, tighten it back down, remove the belt, then loosen it again. Whatever works for you. It's pretty straightforward!

    On the 2 valve 308 is it absolutely necessary to remove the water pipe. On the Mondial it is not. I cannot speak to the QV 308 because I can't remember!! (I have assisted on a couple QV belt changes, but I wasn't the guy in the wheel-well the whole time, so my memory is fuzzy.) YO VERELL???

    Sure, I can measure my cam spacing and diameter over the weekend. You can measure it on a 2V car in about 2 minutes with calipers.

    Hoo boy I'm staying out of that. "Only you can decide what is right for your car and budget."

    Do you happen to have a nice close up shot of the alignment mark on the cam lined up with the mark on the cam cap, as it would look as you peer in through the oil filler? That is the one picture missing from my write up.

    Jonathan
     
  8. tony25

    tony25 Rookie

    Sep 18, 2007
    44
    New Jersey
    Full Name:
    Anthony C.
    What does a Major consist of?
    I have a 1979 308GTS
    Thanks
    Tony
     
  9. CliffBeer

    CliffBeer Formula 3

    Apr 3, 2005
    2,198
    Seattle, Washington
    Full Name:
    Cliff
    Well, that's the guy ranked above a Captain, and below a Colonel. Usually in his mid/late 30's.
     
  10. robertgarven

    robertgarven F1 Veteran
    Owner

    Feb 24, 2002
    5,269
    Ventura, California
    Full Name:
    Robert Garven
    Birdman Sean etc. I am doing this and find this part of your write up confusing,

    "METHOD #2 (Ferrari's procedure)
    First, you remove the cam locks entirely so the engine is free to spin. Now, using your socket wrench on the crank balancer bolt, turn the engine over while watching the tensioners. As the engine turns, the cams create more and less load on the belts at various times as the lobes run over the valves. As a result, at times there is more tension on the belt, pushing the tensioner back against it's spring. At other times, there is less tension on the belt, allowing the spring in the tensioner to push out further against the belt. Watch the movement of the tensioner bearing as you turn, and find the place in the rotation of the engine where the tensioner is pushing out the furthest against the belt. Stop the engine there, and torque down the tensioner to 41 ft-lbs. (5.6 Kgm). Now do the other bank. "

    The further the tensioner pushes out against the belt the more tension it is putting on it not less?
     
  11. Robz328

    Robz328 F1 Veteran
    Silver Subscribed

    Mar 16, 2009
    6,290
    ATL, Georgia
    Full Name:
    Rob Hemphill

    This was an issue in my write-up as well, and Birdman (and Verrell) was correct. Please review our dialogue:

    http://www.ferrarichat.com/forum/showthread.php?t=289560
     
  12. robertgarven

    robertgarven F1 Veteran
    Owner

    Feb 24, 2002
    5,269
    Ventura, California
    Full Name:
    Robert Garven
    I read that and still would like to hear what setting brian or a pro uses or maybe what Steve's comment would be as he is always so precise.. I know I think Dave H or Brian C. uses some kind of harmonic belt tester for tension. I am doing by belts now and would like a definitive answer.

    I understand that when the belt is pushing the tensioner in towards the spring that there is more tension on that segment of the belt , however if i am correct there is less tension on the belt overall after several rotations.

    If the tensioner was pushed out towards the belt and locked there would be less tension on that segment but more overall on the belt as it is even out.

    I am still not sure why everyone is using cam locks. I was one of the early internet guys to mark my belts but if you also put a silver mark on your cam seal and shaft, when the covers are on at PM 1-4 you still have room to wiggle the cam a bit to get the belt on without all that extra. I originally used a cardboard under the cam cap but that made no sense as you could not move the pulley enough to get the belt on. I think there is only one cam on the rear bank that wants to pop of the lobe but even if that does it is closing the valve not opening it so would not cause any damage. The teeth are so far apart it is near impossible to put the belt on with one whole tooth of if you use the cam seal mark. Of course i dont have the cam timing marks on the outside which would be cool!

    This is my fourth time and will report back on any comments I have an early GT4 so the engine is a bit different.
     
  13. Robz328

    Robz328 F1 Veteran
    Silver Subscribed

    Mar 16, 2009
    6,290
    ATL, Georgia
    Full Name:
    Rob Hemphill
    The idea is to present maximum spring force on the tensioner pulley and then fix it by torquing. Turning 2 rotations (per the shop manual) allows it to get to max force since slack is taken over the rotations. If rotating to set spring force, be careful to turn slowly, holding the belt with a free hand. Also, only do one belt at a time and don't push the tensioner pulley into the belt.

    Some degree of cam locking is needed since there is valve spring force present at TDC. If you have marked the line up (marks on pulleys and the background), then, if the belt skips teeth, you can use a socket on the affected pulley to return to time.

    The reason there is no "cam locking" described in the manual, is that the procedure is much more involved; it includes installing the camshafts and pullies and checking valve clearance; the timing is set by placing driving dowels into the cam pulleys. It is a bit cryptic since it is a translation.
     
  14. BLUROAD

    BLUROAD F1 Veteran

    Feb 3, 2006
    6,081
    Tustin Ranch, Cali
    Full Name:
    Enrico Pollini
    I think its time for me to buy another 328 and get back in the game..
     
  15. Fairview

    Fairview Formula 3

    Mar 16, 2009
    1,109
    Waynesboro, Virginia
    Full Name:
    Jeff Ward
    I am following Birdman's terrific write up in changing my cam belts. So far, the only real hitch I've had is that there wasn't enough room to pull the air conditioning compressor out.

    My cam belt covers have to be removed to pull the water pump. (I see now in Birdman's photo, his covers had been "modified" a bit, so I think that is how he got his water pump out of the way). So the solution was to use an air wrench to take off the nut holding the water pump pulley. Then I used a gear puller to pull off the pulley- Success- enough room to get the compressor to where it needs to be- and then on with the show.

    Thanks again Birdman- your write up has made this a fun project, and I'm getting more and more comfortable with my "new" Ferrari because of it.

    Jeff
     
  16. PT 328

    PT 328 F1 Rookie
    Silver Subscribed

    May 1, 2005
    3,955
    I had the same issue a few months back when I completed my belt change (328). I think a few curse words finally got the compressor over the edge. Having done it once it should go much quicker next time around.

    I agree, MyRob and Birdman's write ups were extremely helpful for the first timer.
     
  17. Matto

    Matto Formula 3

    Dec 26, 2011
    2,085
    Mooresville, NC USA
    Full Name:
    Matthew
  18. maurice70

    maurice70 F1 Rookie

    Jan 25, 2004
    4,308
    Sydney
    Full Name:
    maurice T
    I'm going to be replacing the belts in my 328 soon and although I've done this 3 times in the past, I can't recall if I read somewhere on the various tutorials or if I did this the last time I replaced the belts,that when replacing the rear bank belt,was it necessary to turn the motor over so that the flywheel PM 5-8 mark lined up,,or by simply having PM 1-4 lined up as well as the mark on the camshaft cap visble through the oil filer cap and if the cams were locked with a cam lock tool that both belts could be removed and replaced?
     
  19. thorn

    thorn F1 Rookie
    Silver Subscribed

    Aug 7, 2012
    3,322
    Tallahassee, FL
    Both the 1-4 marks and 5-8 marks should be seen lining up, before locking anything and removing belts. They should stay aligned (obviously) until both belts are completely changed, and locks then removed.

    If you cannot get both marks to line up simultaneously, then your cams are out-of-time and you'll need to do far more work than shown in the tutorial.
     
  20. maurice70

    maurice70 F1 Rookie

    Jan 25, 2004
    4,308
    Sydney
    Full Name:
    maurice T
    Thanks Thorn,so that I've understood this correctly,moving the crankshaft until the flywheel mark 1-4 lines up would only mean that the rear bank is at TDC?Then I would lock the rear bank cams,remove and refit the rear belt then set the tension and then repeat the same for the front bank obviously with 5-8 mark lined up?
    I'm pretty sure that's the way I did it last time but that was 4 years ago..
     
  21. thorn

    thorn F1 Rookie
    Silver Subscribed

    Aug 7, 2012
    3,322
    Tallahassee, FL
    No no no. You want both banks at TDC at the same time; both banks are locked (and unlocked) at the same time.

    Assume you've got the cam covers off, but that's as far as you've gone. Old belts are still on the car.

    1. Remove small cover on engine (near oil filter) so that you can (eventually) see 1-4 mark. Remove oil filler cap so you can (eventually) see 5-8.
    2. Rotate crackshaft (clockwise ONLY) until you see BOTH 1-4 and 5-8 marks indexed correctly at the same time.
    3. When you do, lock both banks and proceed.

    If rotation of crank NEVER shows up 1-4 and 5-8 simultaneously, do not proceed with Birdman's belt change tutorial. Seek professional assistance.
     
    gcumbey likes this.
  22. gt500blue

    gt500blue Formula 3
    Silver Subscribed

    Oct 18, 2006
    1,608
    Texas
    Full Name:
    GT
    I'm not sure this is totally correct. I just completed my belt change and all went smoothly. The oil filler cap allows access to the cam marks for cyl 1-4. The only way to see the marks for the forward bank (5-8) is to remove the cam cover. At least that is my understanding. And I was able to set TDC for #1, lock the cams and change that belt. Then lock the other bank cams and change that belt. It was not really necessary to lock both sides at once. I'm sure that is the safest way, but I did not find that necessary to do.
     
  23. gt500blue

    gt500blue Formula 3
    Silver Subscribed

    Oct 18, 2006
    1,608
    Texas
    Full Name:
    GT
    And if you assume the cam covers are off the car, there is no need to remove the oil filler cap :)
     
  24. thorn

    thorn F1 Rookie
    Silver Subscribed

    Aug 7, 2012
    3,322
    Tallahassee, FL
    #49 thorn, Jan 2, 2018
    Last edited: Jan 2, 2018
    Remove the oil filler cap. You can see 5-8 mark there. The 1-4 is seen under the flywheel inspection cover.

    I phrased that very badly - i meant the side covers on the engine, that cover the belts themselves. Not the cam covers.

    If you haven't verified that one bank is correctly timed with the other, then what you've done is basically replaced the belts using whatever timing existed. You've no way of knowing that 5-8 was in the correct position relative to 1-4.

    The reason I lock both banks at once, is because I want to be sure that TDC is maintained for both cams, and relative to both cams, throughout the process. I don't see any advantage - time nor effort nor anything else - in locking 1 cam, changing 1 belt, unlocking it, then repeating all that for the other complete bank.
     
  25. gt500blue

    gt500blue Formula 3
    Silver Subscribed

    Oct 18, 2006
    1,608
    Texas
    Full Name:
    GT
    You are correct that my method does not allow to visually check via marks that the forward bank is timed exact to the rear bank. The car ran great before I did the belts and the last belt change was done by a Ferrari Mechanic here in Austin. He is one of the best and I'm quite certain he did it with timing wheels marks.

    I still contend that the oil cap shows the marks for 1-4. The flywheel cover marks are to confirm that you are not 180 degrees out of phase with the marks on cam for 1-4. The marks for 5-8 are on the bank near the firewall and there is no window to observe. At least, that is my understanding... Am I wrong? the bank with the oil cap is labeled 1-2-3-4. Why would those cam marks show me timing/TDC marks for cyl 5-8??

    Also, I did a basic check with the plug removed and compression gauge to verify I was on the compression stroke, then used a long plastic rod touching the top of the piston in the cyl to estimate Top of the stroke by watching for the peak in upward motion on the compression stroke on forward bank just to give some sense of security. I didn't want to remove the cam covers to be "perfectly" timed with the front bank.

    But the point about locking both banks... I still don't get. Repeating all of what again? I simply locked the rear bank, changed the belt, put enough tension to make sure it did not jump teeth, locked the forward bank and changed that belt. Then set the tension with the Ferrari method vs. Verrel in my case.

    I have one cam locking tool. There was no duplication of any steps required more than locking both banks at the same time.
     

Share This Page