Voltage Regulator / Rough Idle ??

[rbaratt]

Has anyone heard of a voltage regulator causing a rough idle? I saw a post on the internet that showed a merc running rough and "sneezing" and the owner claimed it was the voltage regulator. The post said it is often accompanied with erratic tachometer readings and burnt yellow wires. I do not see any burnt wires to my regulator but I often have tachometer readings when I first start up that are approximately double what the actual RPM's are. I know the tachometer picks up its signal from the regulator. I am fighting with a rough idle condition but I do not want to throw a $150 regulator at this unless it is really causing the issue.

 

[Chris1956]

Disconnect the VR and insulate the yellow wires, and see if the idle smooth's out. The tach gets it signal from the stator charging coils.

What motor are you working on?

 

[rbaratt]

Would I disconnect just the two yellow wires or all the wires to the VR? It's a 75 elpto, 2001 model. Thanks for your help.

 

[Chris1956]

you only need disconnect the yellow wires, I would think.

 

[rbaratt]

Thanks, I did this yesterday and it still ran rough, this weekend I will check some of the basics, timing compression, etc.