Bouncing Tach
#1
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At higher rpm my tach starts bouncing. It's on the money and steady until about 4500 rpm. When I am trimmed out and running 5000 rpm it's all over the place. I replaced the tach and the new one does the same thing? ![Confused](/forums/images/smilies/confused.gif)
Looked for the obvious loose wire and found nothing. Could this be a sign of a bad ground?
![Confused](/forums/images/smilies/confused.gif)
Looked for the obvious loose wire and found nothing. Could this be a sign of a bad ground?
#3
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Not hitting the limiter, checked it with a tach that clips around a spark plug wire and I was right at 4950-5000 rpm when trimmed out. It starts at about 4500 and gets worse as the rpms increase. Under 4500 it's steady and accurate.
![Confused](/forums/images/smilies/confused.gif)
#4
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Location: KENT ISLAND, MARYLAND
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CHECK THE DIST CAP A BAD CAP WILL CAUSE TACH TO JUMP
JOE
AMERICAN PERFORMANCE MARINE
410-573-0057
[email protected]
JOE
AMERICAN PERFORMANCE MARINE
410-573-0057
[email protected]
#6
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Mine does the same. Merc 575SCi
replaced cap & rotor same problem.
Still looking for a cure too
replaced cap & rotor same problem.
Still looking for a cure too
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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
#7
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Mine was doing that last weekend. Spent about an hour touching every connection and trying to move every wire. I didnt find the loose groung I was looking for but when I ran the boat this weekend it was dead on. one of the plugs on the wiring harness must have been loose.