Mystery water in bilge...coming from jackplate bolt?

[Somata]

Cross-posting from BCB forum...

Haven't had as much time to get the boat out the past two months, but headed up into Michigan for my yearly club trip this past weekend and noticed about 1.5-2" of water getting into my bilge when it's just sitting there. Not enough to kick on the auto bilge, but enough that the manual will run for 20-30 seconds to clear it. There appears to be a small water stain below the middle jackplate bolt on the port side. Although it doesn't seem like the amount of water I'm getting could seep in through there, I suppose it's possible. Can I back off the bolt and reseal it with marine grade sealant? And I'm guessing this can happen because of the vibration of the motor?

[Bass Cat Boats]

We don't know the year model though no doubt it requires a good seal no matter how you achieve that.

[Cajunhunter67]

Drain all the water out of the bilge area. Put the plug in tight. Back the boat down the ramp with the rear straps attached.
Back it down enough to get the transom deep in the water, but not enough to float the trailer.
Start looking for water seeping in. If you have grease pencil you can mark the bolt or bolts.
It may very well be a bilge or live well pump that is cracked or leaking. Check your hoses also. I would bet you will easily find the leak.

[RazorCat]

I have a “mystery leak” in my 07 Sabre FTD. It’s intermittent from trip to trip, but I end up with 1-2” of water in the bilge from no apparent leak I’ve found. I’ve tightened all hoses, checked all the bolts, paid attention not to get any backwash when coming off plane, but I still have water in the bilge on some trips. That’s the “mystery” part. It doesn’t occur on every trip. I only use cold packs in the ice chest on most trips, so that’s not the source.
If I ever find the culprit I’ll certainly post it for reference.

[kls2020]

Had a buddy with the same problem with a different brand of boat . We put the boat in the water with the trailer straps on and could see water running into the bilge but could not determine exactly where it was leaking in at. I suggested he take his batteries out , park his boat with the bilge downslope in his driveway , the fill the bilge full of water with the garden hose . Worked like a charm and he could see the leak from outside the boat drizzling down the transom thru a tie down eye .
A little silicone sealant around the bolt threads and problem solved . He had spent months looking for this leak that turned out to be so simple .