308 Timing chain slack question

Bitburger
Bitburger Member
in Parts & Pieces
Can someone please tell me what amount of slack is acceptable in a 308 timing chain? And what is the purpose of the "slider" attached to the inside of the cover?  Mine clicks when I hand turn the motor, which is out and on a stand, Is this normal?

Comments

  • blondwookie
    blondwookie Member
    That looks like a chain slack adjuster in a modern engine. How much chain slop do you have when you turn the engine in the opposite direction? A few degrees or several degrees. I'd suggest contacting 21st century about asking if they still have a true roller timing chain
  • Bitburger
    Bitburger Member
    blondwookie said:
    That looks like a chain slack adjuster in a modern engine. How much chain slop do you have when you turn the engine in the opposite direction? A few degrees or several degrees. I'd suggest contacting 21st century about asking if they still have a true roller timing chain
    So does a 308 ( i believe mine is a 52 model) not normally have a chain slack adjuster?
    When I hand turn the motor there is an audible click with every rotation, there is a fair amount of slack which changes between the upper and lower sections of exposed chain. So when one side is tight the other side is slack.

    When I remove the timing cover and hand rotate the motor there is no click.
  • blondwookie
    blondwookie Member
    What is the amount of slack in your chain with the cover removed 
  • blondwookie
    blondwookie Member
    I'm an engine mechanic by trade
  • Bitburger
    Bitburger Member
    blondwookie said:
    What is the amount of slack in your chain with the cover removed 
    Currently, the motor is on a stand. The distributor is out, and the flywheel is off, so I can't check using the degree method. So, with these limitations what is the best way to accurately check the amount of slack?
  • Bitburger
    Bitburger Member
    blondwookie said:
    What is the amount of slack in your chain with the cover removed 
    Attached are two pics, using my finger pushing outward the difference between the two positions is 7/16ths. Is that a valid test for slack?

    Notice the wire wrapped around the cam gear bolts. Was this factory Hudson?
  • Courtesy Man
    Courtesy Man Expert Adviser
    Yes the wire locking was standard. I don't know specifics about timing chain stretch but long ago I drove my 1952 Hornet from SLC to Reno and Joe Polkas (sp?) may have been rebuilding Hudson engines for Jack Clifford. After listening to my engine running he said the chain was stretched so much that the chain rubbed against the timing cover and you could hear a brushing sound. He told me to slow down on the way home or chain would slip a tooth. Made it home and changed out the chain and it was like adding extra horsepower! If you can stretch the chain to hit the timing cover it is real bad! If you see scrape marks on the cover then it is  probably from the chain rubbing.  Gert
  • Glowplug
    Glowplug Expert Adviser
    October 1951 Hudson Merchandiser has the following information


    The timing chain snubber or silencer was changed and in the last iteration it was:




  • 54coupe
    54coupe Member
    That’s too much slack.
  • Bitburger
    Bitburger Member
    54coupe said:
    That’s too much slack.
    Ok, thanks
  • Bitburger
    Bitburger Member
    Glowplug said:
    October 1951 Hudson Merchandiser has the following information


    The timing chain snubber or silencer was changed and in the last iteration it was:





    Excellent post Glowplug. How interesting that Hudson had a Tech Service bulletin for this problem. Thanks

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