Cam Gear Drive Backlash?

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by BEDNAR1320, Feb 13, 2019.

  1. BEDNAR1320

    BEDNAR1320 Member

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    On my engine (New Century block) the gear drive front cover has quite a bit of backlash, I haven't actually measured it, but it's about 1° of crankshaft movement, so it's more than I'd like. It's a Fowler cover/drive and I contacted them to see if a slightly oversize idler was offered, no such luck. The only thing I can think of is to enlarge the dowel pin holes and try some .015 offset dowel pins to move the cover closer to the crank/cam. Anyone run into this before? Any other ideas? I really think that with too much backlash it's hammering on the crank and cam.
     
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  2. Bill Naves

    Bill Naves Member

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    never really thought about it, but will it get tighter or looser when the block heats up ? Anyone?
     
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  3. Bill Naves

    Bill Naves Member

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    dont forget by moving the cover, the pump alignment will move
     
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  4. BEDNAR1320

    BEDNAR1320 Member

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    I thought about that, but I don't think .015 or less would be an issue.
     
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  5. REEHL EQUIPMENT

    REEHL EQUIPMENT Authorized Merchant

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    The crank seal will change, too.
     
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  6. BEDNAR1320

    BEDNAR1320 Member

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    It will, but I don't think .015 would be enough to cause an issue
     
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  7. REEHL EQUIPMENT

    REEHL EQUIPMENT Authorized Merchant

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    Is it loose between the idler gear and crank gear, or between the cam gear and idler?
     
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  8. Nemo963

    Nemo963 New Member

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    I had a Milodon cover style 3-gear drive in the early 90’s for BBC. It had oversised dowel holes on both sides with a bunch of offset inserts that allowed you to move the gear around until it was correctly set (it said two pieces of newspaper should just cut when rotated through the teeth between both the cam and the cam and the crank and the idler). Took some fiddling but once it was set you were good until you changed blocks or had it line bored. Never had problems with cam drive fuel pump or crank seal.
     
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  9. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    Getting a hemi should fix that.
     
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  10. BEDNAR1320

    BEDNAR1320 Member

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    LOL! Hemi-roid?
     
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  11. BEDNAR1320

    BEDNAR1320 Member

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    I set one of those up on my last engine. Worked good.
     
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  12. promodracer

    promodracer Member

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    Would plating the gears help. Just a thought
     
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