Since this problem began after you added the relay for charging the camper battery, you might want to temporarily disconnect your modification, just in case it is loading down the battery and preventing the starter from getting enough current. I consider this an unlikely scenario, think you probably just have a "tired" solenoid as others have said, but it's worth eliminating that possibility while you're checking all the grounds and such.

__________________

"Buster" in the '95

Our all-Diesel family
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