Let me start off by saying that there was probably no repair manual that was written specifically for your 1986 Pinnacle Motorhome. Not enough individual brand and model RVs are sold annually to warrant any publisher from trying to sell a Maintenance and Repair Manual that is solely written for individual, year, make and model RVs. In other words they would not sell enough Maintenance and Repair Manuals to make money.
The good news is that the majority of equipment that is installed on an RV is universally used by all RV manufacturers. So there are quite a few general RV Maintenance and Repair Manuals on the market. There are also Maintenance and Repair Manuals written for the different types of chassis used by RV manufacturers. So what you are looking for is a good General RV Maintenance and Repair Manual.
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