Augoose
Lieutenant Junior Grade
- Joined
- Mar 21, 2010
- Messages
- 1,223
This is a 1989 4.3 mercruiser w/alpha 1
Yesterday I noticed my tach giving inaccurate readings. At idle, its accurate. After a few moments when I get up to speed where it should be in the 2000- 2500 range, it will read about 3800 or so. Then if I slowly increase speed, the tach will slowly increase as well, going above 4000, however I'm certain the engine is not running nearly that fast. Then if I drop speed just a little bit, the tach seems to drop back down to the expected range of around 2700-3000. I'm nowhere near WOT during these tests. Engine seems to be running fine the whole time. On Saturday, the tach was behaving completely normal.
Could this be a bad gauge?
Any suggestions as to where to look for faulty connections? I examined the manual for my engine and it looks like I have wires leading from the gauge to ground, ignition switch, alternator and coil. I'll check for good connections at all those locations but is there anywhere else to look?
Thanks
Yesterday I noticed my tach giving inaccurate readings. At idle, its accurate. After a few moments when I get up to speed where it should be in the 2000- 2500 range, it will read about 3800 or so. Then if I slowly increase speed, the tach will slowly increase as well, going above 4000, however I'm certain the engine is not running nearly that fast. Then if I drop speed just a little bit, the tach seems to drop back down to the expected range of around 2700-3000. I'm nowhere near WOT during these tests. Engine seems to be running fine the whole time. On Saturday, the tach was behaving completely normal.
Could this be a bad gauge?
Any suggestions as to where to look for faulty connections? I examined the manual for my engine and it looks like I have wires leading from the gauge to ground, ignition switch, alternator and coil. I'll check for good connections at all those locations but is there anywhere else to look?
Thanks