So I recently purchased a 94 Aquatron 1800 with a 3.0 Mercruiser. Supposedly the boat had an issue where it wouldn't start back up when hot after it had been shut off and the PO had it diagnosed by a "professional" who said it needed a distributor. I knew from the start that that wasn't a possibility, maybe a ICM or a coil, but the distributor itself having that Issue was 99.9% improbable. Fast forward after I got it home and did a little diagnosis of my own I found a fuel pump that wouldn't pump and after disassembling it I found a nasty mess and bad ignition switch. Fixed those and it fired right up, I'm assuming that there were no weird noises as this is my only my 2nd boat and the other has never even been cranked since I've owned it. It sounds decent from just idling on the muffs, no noises that I haven't found to be normal from reading. However it's idle is rather weird. When I first got it running I disconnected the throttle from the carb and adjusted it to around 700 or so as per my reading of other topics. Cranked it up the next day and it was around a 1k after warmed up. I can't seem to get the idle to stay the same, it will fluctuate between 700-1000 rpm's. I was thinking that maybe it could just be dirty and need to be freshened up but like I said I know nothing about these motors. The motor itself bounces around a bit more than I think it should although I've read that the 3.0's were bad about roughish idling. I'm looking for a little more knowledge on what my next steps should be. I haven't put it in the water yet, if all things go as planned it'll be on the water Wednesday. Hopefully someone can point me in the right direction so when I get it in the water I can get it dialed in.
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