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2000 R1100RT cutting out

Dana Hager did a great job explaining how to rebuild the HES. I am grateful for his excellent instruction sheet. So, I don't want to be disrespectful in pointing out a slightly better material choice. As I have previously posted, I am not convinced that his wire choice is the best solution.

Wire failures are generally caused by one of the 4 conditions:

1. Casing threshold temperature is too low
2. Corrosion of the wire (yes, solid copper can corrode)
3. Overload of current through the wire.
4. Movement causes breakage.

Dana's solution only addresses the first condition. I am not convinced that there isn't a corrosion problem. One way to avoid the 2nd condition is to use Marine grade wire. That is, tinned wire.

I would use an oversized wire that is tinned along with a high-temp casing (such as TFE or other material). This would address the first 3 conditions, instead of just the 1st one. You only want to do this job once.

It is also important to make sure that the wire you order is solid copper, and not CCA or CCS. CCA and CCS wire is become popular due to the economy.

Having rebuilt quite a few now here are my observations:

1) almost always insulation breakdown due to crystallization.
(the odd one is an actual sensor failure)
2) None showed evidence of corrosion although I use tinned wire as a replacement.
3) Overload is not an issue as the sensor is rated at a MAX of 40mA, any more than that and no more sensor. Typical running current is way less than that.
22ga is plenty and any bigger and the splices bulk up and interfere with installation. My favorite is 24ga teflon. Be sure to use temp rated heat shrink tubing as well.
4) I have never witnessed any wire breakage, always crumbling insulation. I cut every dud apart to find the failure

My $.02 worth based on actual history.
 
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