range hood

Well that would depend on if there's something causing it to short out or partially short out. Do you feel heat anywhere...being generated..or is their a smell of smoke? Why not just replace the fan motor and/or replace the wiring?

Does the voltage jump to 120 when you turn 'em off

Or Bema, by "hard wired" do you mean there's no switch that wold let you do so

Or by "…use range hood…" do you mean it's somehow disconnected when not in use

no smell of smoke and what wire I can feel is fine I do plan on rewiring but the attic here is well over 100 degrees in the summer and want to wait till the fall

90 volts is the what the main wires read on the meter the only on off switches are the ones for the light or fan

Sorry Bema if I seem dense but you've made ref to "...every other thing…" being at 120 v so by "main wires" at 90 v I assume you mean those leading to the hood. I also assume that light and fan must be the only loads on the hood. So what voltage do get with just the fan off? or just the light? or both?

The range hood should have an accessible junction box. Disconnect the circuit from the hood and then take your voltage reading. If you then read 120V as you should, the problem is in the hood and not in the attic. If you do not want to fix the hood now, leave it disconnected and cap off the wires.

sorry it took so long to get back to ya every other thing refers to those on the same circut breaker at 120v just the wires that feed the hood range are at 90v

sorry it took so long........I did access the junction box and it is there that the 90v occures in the lead wires from the circut breaker every thing else on that circut breaker reads 120v

Okay Bema the problem is clearer. Poke around with your voltmeter to find that missing 30v. There might be for instance (1) a miswiring that places an intervening load in series with the hood hot wire or (2) more likely an open circuit in neutral that connects the hood return instead to earth ground

Very, very unlikely the wiring is okay but (3) you'll find this 30v divided between the two. That is for instance 15 v from main hot to hood hot and 15 v between main return and hood return, caused typically by a short in the motor. In this case however one would expect wires to the hood getting very hot

Did you disconnect the wires to the hood and then take your reading?
What else is on that circuit?