350 distributor gear puzzling UGLY wear

Discussion in 'Small Block Tech' started by gsjohnny1, Nov 28, 2021.

  1. gsjohnny1

    gsjohnny1 Well-Known Member

    pics of gear wear on the dragster. wears one side ugly. i mean ugly. this was a new gear treated and polished. second time it has happened. could be because of solid lifter cam??? never had the problem this way with the hyd cam, just wear. looking for ideas.
    since i don't do pics, somebody else will post them.
     
  2. Mart

    Mart Gold level member

    John, how does the cam gear look?
    This bad.....
     

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    Last edited: Nov 28, 2021
  3. Fox's Den

    Fox's Den 355Xrs

    galley holes plugged.jpg I guess I am about to find out if a solid lifter cam will wear out the dist gear since I bought a Schneider solid cam this year.

    The only thing I would have to ask is are the oil holes in block open enough.
    I do have the square pickup that the 455's had used I think it had a larger tube with that.
    my crank is cross drilled if that means anything. I do have a couple plugs on the galley on drivers side. Not sure what that was for now, redirect oil on the cam bearings possibly been too long ago to remember.

    here is a pic
     
    Last edited: Nov 28, 2021
  4. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Warped timing cover? The distributor isn't square to the cam gear.
     
  5. Mart

    Mart Gold level member

    You think you'd already have gear wear running those H.V. gears all those years.
     
  6. Mart

    Mart Gold level member

    The one sided wear is weird though... shouldn't it be evenly worn?
     
  7. BrunoD

    BrunoD Looking for Fast Eddie

    Check for wear in the inside of the distributor ittself,t might be out of round.Bruno.
     
  8. Mart

    Mart Gold level member

    Take an old timing cover, cut a B F hole in it. Get your rear end gear marking compound out and check the cam/ dist gear mesh....
     

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  9. gsjohnny1

    gsjohnny1 Well-Known Member

    last rebuild changed the t/c cause the dist hole was stretched out. run a stock gm hei. never any issues. will go over it.
    the old hyd cam is looking better.
    got a boat load of problems i have to solve since last rebuild.
     
  10. Mart

    Mart Gold level member

    Here are John's gear pics....
     

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    Mark Demko likes this.
  11. gsjohnny1

    gsjohnny1 Well-Known Member

    thanks mart.
    now...who has an answer
     
  12. Dano

    Dano Platinum Level Contributor

    Good idea at least in theory Marty. Probably should be done on all Buick rebuilds. Of course under load it could change & that'd be assuming the covers are consistent but should give a pretty good indication plus a new use for at least one old cover, lol.

    There's the crank driven pump too on the later v6's but IIRC there's some inherent problem w/using them on the older cars. Don't recall what it is off hand? It'd be interesting to see what the HP difference is between the 2 and also compared to a belt driven external pump.
     
  13. Fox's Den

    Fox's Den 355Xrs

    maybe the larger gears like I use are more stable in the system and with the larger gear area with more oil there is not as much stress as first thought. I have ran this almost 30 yrs now. Dis gear 350 Buick.jpg
     
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  14. Mark Demko

    Mark Demko Well-Known Member

    Good possibility!
    The ONLY issue I've ever had running the HV pump gears was blowing cheap filters off way back when.
    This build with a new TA timing cover, I noticed a slight drag when I mocked up the pump and distributor on the bench, I tried this and that, called TA they gave me some suggestions, tried those, they didnt work.
    Been running the combo for 2 seasons with HV pump, havent checked my distributor gear lately, probably will when I pull the engine for my TA heads and SRE oil pan.
     
  15. JESUPERCAT

    JESUPERCAT No Slow Boat

    John go to an external oil pump :D
    What oil/weight are you running?
     
  16. Mart

    Mart Gold level member

    That gear looks pristene. My suggestion....don't take that cover apart.:D
     
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  17. Fox's Den

    Fox's Den 355Xrs

    I rule out the solid lifter cam doing in the gear since the lifters are supposed to keep the cam pushed to the back of the engine.

    But is the wear on gear from the camshaft pushing foreword or is the distributor moving up or down

    Is the shim correct between the gear and the dist housing. I think that was .010-.015

    There has to be something different in my motor since I have never worn out the gear on either part and I run those large gears. That was the way TA set it up when I bought the cover.

    or does 7500 rpm shift have something to do with it. :eek:

    I also run the MSD dist so maybe that is the difference I do not know just throwing something out there.

    how about the gear pocket did the gears wear the top of the pocket or the bottom like it would normally do
    that part has to show some kind of wear since something was making the gear wear out and those two are connected.

    When the distributor is in, is there movement up and down on the shaft could it be there was pressure pushing on the oil pump shaft which pushed the gear up and caused to be out of center?

    The only thing that I do different than most is I do run Mobile 1 10-30 and have ran this the entire 28+ years this motor has been together. 4 qts 10-30 2 qts of the 15-50 is my mix no zinc never used it go figure.

    all I can think of right now
     
  18. Mart

    Mart Gold level member

    John, looks like some water was introduced by the tell-tail milkshake residue.
     
  19. gsjohnny1

    gsjohnny1 Well-Known Member

    no room for an external pump. chassis too narrow.
    run 4qts 10-30 amsoil. before forged ran plain 10-30
    never heard of larger dist gear. have run stock pts, msd d/pts and stock hei. have a boat load of worn dist/cam gears.
    maybe the 350 is not for hi rpm. lol
    this is twice that the teeth on one side shows that its 'jumping' and wearing the top of the teeth
    b4, gear teeth were just worn out.
    will check cam bearing clearance
     
  20. gsjohnny1

    gsjohnny1 Well-Known Member

    mart, milkshake.....thats how i broke in my hyd cam, oil and h2O. no wear on that cam at all.
    then i fix those leaky holes in the heads. think the frze plugs rotted out now.
     

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