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308/328/Mondial Timing belt replacement tutorial

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

  1. thorn

    thorn F1 Rookie
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    Aug 7, 2012
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    #51 thorn, Jan 2, 2018
    Last edited: Jan 2, 2018
    I know for certain that the flywheel shows PM1-4.
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    Here's the oil filler view:

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    However, I'm going to stop declaring 1-4 vs 5-8 markings at this point... All of my knowledge is based on what I've read from others (and doing the procedure), and it's very possible I've misunderstood which markings are which thing - although I do know there's a mark @ the flywheel, and another at the oil fill.

    So, I don't want to confuse the issue further on the markings, locations, etc at the risk of a) being wrong and looking stupid and b) encouraging someone to go down the wrong path. And if I'm wrong (and you're right), I certainly wish to be corrected so that I've got it right too.
     
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  3. Glassman

    Glassman F1 World Champ
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    The marks seen thru the oil filler cap are cylinders #1 thru #4. (why would Ferrari mark cylinders #5 thru #8 on the 1-4 cam?????
     
  4. thorn

    thorn F1 Rookie
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    Yeah, it was exactly that bit of a "doh" realization i had (after I read your post) that made me realize I should STFU for a bit and let the adults talk about what the marks indicate.

    I'm still going to lock both at once, though. ;)
     
  5. gt500blue

    gt500blue Formula 3
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    There is no looking stupid here.. we all learn. I learn much more here than I can ever pretend to instruct or correct anyone else. I just know that the marks on the fly wheel are for 1-4 and they are used to make sure that when you view through the oil cap, that mark needs to also be lined up for 1-4. You need two sets of marks to confirm TDC since the crank and cam shafts spin at a 1:0.5 ratio. So you need to check both sets of marks. If they are not both lined up, then you need to turn the crank shaft again so you are not 180 Degrees out of phase. That's all.
     
  6. maurice70

    maurice70 F1 Rookie

    Jan 25, 2004
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    Thanks guys,I just wanted to check if l was doing it right,,
    GT,what l meant was that you can only lock one cam bank at a time at TDC,
    say you do bank 1-4,after verifying that flywheel 1-4 mark and oil filler cap mark line up l lock that bank...
    Then l replace that belt only as that's the only bank that is at TDC,
    l then set the tension as per the Ferrari WSM..
    Then l bring the front bank to TDC with the flywheel mark set st 5-8,(obviously like stated we can't check the cam cap mark unless we remove the front cam cover,,)
    then l lock that bank and remove and refit that belt and again tension it as l did the other..
    l'm replacing the bearings of course....
    l'm not sure if l'm doing it the long way or the wrong way but that's the way l have done it in the past but l thought l would ask the question again to find out..

     
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  8. Glassman

    Glassman F1 World Champ
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    QUOTE="maurice70, post: 145748965, member: 4226"]Thanks guys,I just wanted to check if l was doing it right,,
    GT,what l meant was that you can only lock one cam bank at a time at TDC,
    say you do bank 1-4,after verifying that flywheel 1-4 mark and oil filler cap mark line up l lock that bank...
    Then l replace that belt only as that's the only bank that is at TDC,
    l then set the tension as per the Ferrari WSM..
    Then l bring the front bank to TDC with the flywheel mark set st 5-8,(obviously like stated we can't check the cam cap mark unless we remove the front cam cover,,)
    then l lock that bank and remove and refit that belt and again tension it as l did the other..
    l'm replacing the bearings of course....
    l'm not sure if l'm doing it the long way or the wrong way but that's the way l have done it in the past but l thought l would ask the question again to find out..[/QUOTE]

    You can just lock both banks at TDC #1 thru #4. You actually don't even have to go to TDC (if you have the balls) as long as the new belts are installed exactly how the old ones were removed. Marking the belts and the pulleys helps to insure that.
     
  9. andyww

    andyww F1 Rookie

    Feb 7, 2011
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    Set to 1-4 on flywheel
    Mark pulley rims with a straight edge placed across the centres (4 marks per bank)
    Mark lower drive pulleys against belt guards next to pulleys.
    Change both belts
    Check markings still line up
    Set both tensions.
     
  10. thorn

    thorn F1 Rookie
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    I appreciate that GT - very gracious of you. :) I think I wasn't realizing that the 2 marks are for the 180 degree confirmation, not each cam. Big difference. I'm glad we talked that though, as I didn't want my confusion rippling down the line to a new generation of home DIY. ;)
     
  11. yelcab

    yelcab F1 World Champ
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    Nov 29, 2001
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    You guys are overthinking this !
    Bring number 1 to TDC, change both belts without moving anything.
     
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  13. andyww

    andyww F1 Rookie

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    As I mentioned above. Absolutely correct. To be honest there is a good case for all the posts on this thread in the past 2 days to be politely "moderated" as none of them add any validity to this procedure and likely just cause confusion.
     
  14. maurice70

    maurice70 F1 Rookie

    Jan 25, 2004
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    I get that now,my only query was that if you didn't bring banks 5-8 to TDC and something moved,then you wouldn't have any reference point..lm truly not trying to overthink this and lm not trying to reinvent the wheel either,
    my point was that if you lock bank 1-4 at TDC and something moves,you always have that TDC as a reference point..
    That's why I thought to do it the way I have done it in the past,it probably adds another 1/2 hour to the job I guess,,but by no means am I trying to change the way that everyone else does it..
    Moderators feel free to remove the past 2 days of threads..
     
  15. andyww

    andyww F1 Rookie

    Feb 7, 2011
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    But why do you need to have a reference point of 5-8 at TDC?

    You can use 1-4 for both banks. There is only one crank so one bank cant move without the other moving!
     
  16. thorn

    thorn F1 Rookie
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    That's why you lock the cams to make sure nothing moves.
     
  17. Andy 308GTB

    Andy 308GTB Formula 3
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    Jun 2, 2004
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    This. But no one wants to believe that it's a simple job!

    I actually use a small spirit level to put the marks on each pulley but I won't fall out with you over that.
     
  18. yelcab

    yelcab F1 World Champ
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    Nov 29, 2001
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    Alright now that the drama is over.

    The belts on a 308-328 series are done mostly on a lock and swap procedure because the power output is not all that much and not really sensitive to a few degrees out of specs. Having said that, the flywheel fit to the back of the crank shaft is pretty sloppy and the engine at the time of major assembly should be timed correctly to ensure that the 1-4 mark is reasonably correct. When you are doing the timing belt job, you have to be extremely careful of not moving the crankshaft as there is no provision to lock it in place.

    I still do my own valve timing with the degree wheel because I want my 328 to pump out 275 HP and my labor is free. You do what you want on your car.

    As for why there are 1-4 mark and 5-8 mark on the flywheel, it is to check dynamic timing when the engine is running.
     
  19. yelcab

    yelcab F1 World Champ
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    I did this too on the front pulley for assembly purposes because the flywheel is so hard to get to. But, the most accurate method is still the degree wheel.
     
  20. joeyy

    joeyy Karting

    Nov 11, 2003
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    I have done this twice already. Do get the cam locks from Verell they are an insurance policy that are easy to use and make the job move faster.also make all markings on pulleys and belts. When you have things apart its easy to second guess yourself, make every effort to have references that you can trust and go back to. Also Do take pictures. when you have the confidence because of proper preparation the job goes much smoother and faster.
     
  21. kcabpilot

    kcabpilot Formula 3

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    #68 kcabpilot, May 16, 2018
    Last edited: May 16, 2018
    Having just removed both heads on my engine I can offer a few observations. The PM 1-4 mark on the flywheel coincides with the hashmarks on all four cams aligning with the marks on the front end journal caps. There are also marks on the cams between the seal and pulley that align with pointers attached to the belt cover back plates. So, in regards to alignment and belt change, the PM 5-8 mark on the flywheel has no bearing or use. I believe the primary use for that mark would have been to set ignition timing on the older breaker point cars where it was adjusted by moving the distributor while using a timing light.

    Another observation - when #1 is at TDC #4 is also at the top of it's travel and all four pistons on the 5-8 bank are even at mid-point of the cylinders.
     
  22. cobolman

    cobolman Rookie

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  23. PT 328

    PT 328 F1 Rookie
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    I just checked it and you are right, clicking the "service procedures" link from the top of the home page doesn't work. However, if you scroll down on the home page and click on the direct link to the "timing belt change" it brings up the correct page.

    Home Page: http://www.birdman308.com/
     
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  24. cobolman

    cobolman Rookie

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    That did the trick. Thanks!
     
  25. Nino1964

    Nino1964 Karting
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    I feel like block and swap has some risk, especially with those original cam gears. The original cam gears are very difficult to use because the dowels have to match up perfectly in order to align the belts. You need to have the tension on the tensioner bearing side of the assembly in order to keep the alignment correct. If you screw up the tension side and you will risk movement of your timed cam/crank assembly when installing the belt. I have done the lock and swap before but it left me with the idea that my engine wasn't set up correctly.
     
  26. mwr4440

    mwr4440 Four Time F1 World Champ
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    Huh?

    Can you add some detail to this feeling?

    It is 100% IMPOSSIBLE to NOT put on a belt 100% correctly UNLESS you let a cam 'wander.'

    Self-Applied 'Index Marks' crossing the belt and pully and then transfered to the new belts INSURE the cams DO NOT 'WANDER' while no belt is in place.

    Self-made cam locks from a hocky puck or wood block and looong bolt and nut, work too.
     
  27. Glassman

    Glassman F1 World Champ
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    Please elaborate on these dowels that need to be lined up. I don't get at all what you are saying. With the cams locked , marked, belts marked etc. nothing can move without noticing it.
     
  28. Nino1964

    Nino1964 Karting
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    #75 Nino1964, Jun 3, 2020
    Last edited: Jun 3, 2020
    You can remove the dowel pins so that the cam wheel rotates without rotating the camshaft. This allows for an easier install of the belt. There are also some nice after market pulley sets that have a much easier locking mechanism than the OEM dowel pin system.
     

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