Erratic temp and fuel gauge

[Greyhound101]

A few months ago, I posted that my temp and fuel gauges were 'dancing' when operating the tractor at anything above an idle. I've checked my ground (even ran a seperate wire back to the battery to make sure I had a good ground) and the 12v+. My multimeter shows a voltage of between 14.5v-15v (depending on RPM)at the wiring cluster. I've measured the ground contacts on the back of the cluster and there is little to no resistance so I should have a good ground at both gauge points. In my I&T shop manual, it shows a voltage stabilizer in the circuit behind the cluster. I called the local dealer and they told me that the 4610 has never had a voltage stabilizer? What (if a non-stable voltage isn't) could be the problem? If the stabilizer wasn't $71.54, I'd go ahead and buy one and install it just to eliminate that variable. I'm stumped.

 

[chevdud97]

Is it an alternator ? If so one of the diodes in the alternator could have gone bad throwing ac voltage inline.

 

[RickB]

15V isn't doing your battery or any light bulbs that may be powered any good. I'd look into an alternator repair or replacement. 4610 does not have a oltage stabilizer in the instrument panel.

 

[Greyhound101]

The reason why I'm hesitant to think it's alternator problem is that I didn't have this issue until after the instrument cluster was re-wired due to rats eating EVERY wire behind the cluster. I'm wondering if there is a sensory wire or something that is not 'telling' the alternator where to regulate? Is the voltage regulator built into the alternator itself? I'm lost on this one.

 

[RickB]

That is what is known as "the rest of the story".
Some 4610's will have external regulators, some won't. Some may even have a battery temperature sensor as part of the charging circuit. High output voltage coud very well indeed be a voltage sensing problem.

 

[Greyhound101]

Oh boy! LOL. I wonder where an external regulator might be?

 

[RodinNS]

External regulators were mounted on the firewall/ front of the fuel tank area. Probably have Motorolla Solid State on it... IIRC it's a small box about 2"x2" or so.

Rod

 

[Anonymous-0]

You have a bad ground to the instument cluster.

 

[Greyhound101]

As said in my initial post, I even ran a new wire directly to the battery to rule out a bad ground. Resistance from the battery to all grounding points on the cluster measure near zero. I don't think a bad ground is the problem. I'm leaning more toward voltage regulation/stabilization being the culprit.

 

[kyhayman]

My 7610 low profile has the same problem on an irregular basis with the gages, voltage comes out ok though. The last time it happened there was a bad diode in the alternator. Also, get a dead battery in about a week. Finally solved the battery problem with a disconnect on the ground wire and tolerate the gage problem.

 

[JMOR]

(quoted from post at 07:15:53 06/15/10) As said in my initial post, I even ran a new wire directly to the battery to rule out a bad ground. Resistance from the battery to all grounding points on the cluster measure near zero. I don't think a bad ground is the problem. I'm leaning more toward voltage regulation/stabilization being the culprit.

Isolate the charging system causing voltage surges & influencing your gauges by disconnecting the alternator and run for awhile only on battery & observe the gauges.........same or now steady?