Tach jumps at hi RPMS. HELP!
05-31-2005 | 11:27 AM
#1
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From: Virginia Beach, VA
Tach jumps at hi RPMS. HELP!
My starboard Motor Tach Wants To Jump 400-800rpms While The Motor Is At 4k or above.
Have Ruled Out The Tach Due To swaping tachs.
Had The Scan Tool Hook Up Which Show The Rpms To Hold seady at 4k or whatever RPM it was turning.
New Cap/Rotor.
What can cause this????
Have Ruled Out The Tach Due To swaping tachs.
Had The Scan Tool Hook Up Which Show The Rpms To Hold seady at 4k or whatever RPM it was turning.
New Cap/Rotor.
What can cause this????
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BillR
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05-31-2005 | 11:37 AM
#2
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From: Sunny, AZ
Re: Tach jumps at hi RPMS. HELP!
I had a very similar problem that eventaully got to the point were it would jump around at any RPM. It ended up only being a bad electrical connention in one of the bulkhead connectors in the wiring harness. Trace down the wires from tach to motor check all plugs in connections and clean them out (WD-40 works good). Hopefully its as simple for you as it was for me, Good Luck...
05-31-2005 | 03:03 PM
#3
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From: CHESAPEAKE,VA
Re: Tach jumps at hi RPMS. HELP!
[QUOTE
=BillR]My starboard Motor Tach Wants To Jump 400-800rpms While The Motor Is At 4k or above.
Have Ruled Out The Tach Due To swaping tachs.
Had The Scan Tool Hook Up Which Show The Rpms To Hold seady at 4k or whatever RPM it was turning.
New Cap/Rotor.
What can cause this????[/QUOTE]
BILL WHY DON'T YOU CHANGE COMPUTERS AND SEE IF IT HAPPENS.
=BillR]My starboard Motor Tach Wants To Jump 400-800rpms While The Motor Is At 4k or above.
Have Ruled Out The Tach Due To swaping tachs.
Had The Scan Tool Hook Up Which Show The Rpms To Hold seady at 4k or whatever RPM it was turning.
New Cap/Rotor.
What can cause this????[/QUOTE]
BILL WHY DON'T YOU CHANGE COMPUTERS AND SEE IF IT HAPPENS.
05-31-2005 | 05:02 PM
#4
Charter Member#330
Joined: Oct 2000
Posts: 2,377
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From: CHICAGO, IL
Re: Tach jumps at hi RPMS. HELP!
Just had one at from idle to 3000 rpm all was ok over 3000rpm the tach would jump to 7000rpm traced out all the grounds, switched tachs, changed modules, checked all connection on big plug.
Landed up being a bad coil. Funny thing is the motor ran fine.
Mark
Landed up being a bad coil. Funny thing is the motor ran fine.
Mark
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06-01-2005 | 07:15 AM
#5
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From: Virginia Beach, VA
Re: Tach jumps at hi RPMS. HELP!
I have new ignition coil.
I'll try the grounding thing and swap computers.
I'll try the grounding thing and swap computers.
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BillR
'00 Scarab Sport 302 CC
'02 Cigarette Top Gun TS
'02 PQ 340
'00 PQ 280
'98 Scarab 22
'97 Baja Outlaw 20
'72 Checkmate
'65 Glastron
BillR
'00 Scarab Sport 302 CC
'02 Cigarette Top Gun TS
'02 PQ 340
'00 PQ 280
'98 Scarab 22
'97 Baja Outlaw 20
'72 Checkmate
'65 Glastron
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