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1981 XJ750 Seca won't start

Discussion in 'XJ Technical Chat' started by RusteeGold, Jul 21, 2021 at 11:07 PM.

  1. RusteeGold

    RusteeGold Active Member

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    I've got a 1981 XJ750 Seca that won't start. The battery is fully charged - 12.84 volts. When I hit the starter switch I can hear the starter relay click and the battery voltage drops top 12.80. I removed the starter and did a bench test - the starter seems to be good - it spins quickly and freely when I apply voltage to it on the bench. Not sure what to check next.

    Thanks in advance for any help.

    Rustee Gold
    1981 XJ750 Seca
     
  2. Franz

    Franz Well-Known Member

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    How long have you owned the bike?
    Have you got a Haynes manual for your bike?
    Do you have the original Yamaha fusebox?
    Have you checked your valve clearances?
     
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  3. Mechanic1978

    Mechanic1978 Active Member

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    Will it not crank over? A starter motor can test good on a bench, and still be bad. It is when its under a load that they can fail... Clicking solenoid usually means low, or not enough power to operate the syatem. And yes a battery can also test good, and fail when under a load. easiest way is to use a known good starting battery...(car/truck/riding mower etc..)

    Does engine turn over when cranked at all?
    Or does it not turn over the engine and you just hear solenoid clicking?
    If it cranks engine, make sure no saftey relays are preventing spark.
     
  4. RusteeGold

    RusteeGold Active Member

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    Fortunately I have 2 Secas so I decided to swap starters. The other starter worked like a charm in the "bad" bike, so even though the "bad" starter passed the bench test, it did not have enough power to work in the bike - so I'll be rebuilding the bad starter.

    thanks for the insight Mechanic1978.

    Rustee Gold
     
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