Wait, the starter positive lead may always show continuity to ground. They're designed to pull a high load. 100A at 12V is only 0.12 ohms. Most handheld testers are going to indicate continuity with 0.12 ohms. Some cheap meters have nearly 0.1 ohms just in the leads. The proper way to check a short to ground with a starter would be to measure the current it draws.
Unfortunately, the manual doesn't list what the normal current is, so I don't have anything to go by.
Unfortunately, the manual doesn't list what the normal current is, so I don't have anything to go by.