Logo
FULL SITE MENU

Tachometer not working properly

B

brian79cj

New member
I have a new to me 1986 225 Four Winns with a 5.0 mercruiser 230 hp Alpha 1 . All my gauges work properly except the Tach. When turn key on the tach pointer goes well below zero. When running what I think is close to WOT it says approx. 1200 RPM. Does anyone know if this is a tach problem or a wiring problem? I cannot find a matching replacement. I would hate to replace just the tach and not have them match. Any help would be appreciated.
 
Some tachs have a switch on the back for different number of cylinders.I have heard that if you cycle the switch and then select the proper range it can solve the problem.Connection at coil maybe.
 
In my opinion if those are the stock guages your not going to find a matching tach that works properly. You can do the switch thing and if it works that is just a bandaid, that means moisture intruded the guage and it will fail again. You can get a complete set for reasonable on ebay I have been happy with the set of faria guages I just went to their website and got the kit number and they look great.
http://www.ebay.com/itm/Faria-Euro-...ash=item3d402ee66a:g:2jYAAOSwDrNZXRdU&vxp=mtr
 
I checked and cleaned coil wires, turned selector switch in back, jumper wire from coil to tach. The tach still is all over the place. It's time for a new one. Thanks for help guys.
 
Faria gauges are well made. Needed an electronic gauge to replace the mechanical one on mine when I had the engine swapped 11 seasons ago. Found a used on on ebay that I bought "to get me thru the rest of the season". ( The promised reengine project that started end of Feb and promised launch N/L/T May30 didn't get splashed until Aug 20!) Still on the boat and working perfectly. Not an exact match stylistically with the original or other gauges, but complements them nicely.
 
Back
Top