I have a 98 250DA. Replaced battery with larger size so of course I had to install larger battery hold-down and drill some holes to mount it. I am also replacing wall mounted battery charger which has different mount hole pattern than previous. My question: How thick is the wall and floor in the bilge? Am I creating leaks? What is proper method for mounting stuff with screws in the bottom of this boat ? Thanks.
Drilling screw holes in the bilge
- Thread starter stwischu
- Start date
It all depends on where you're doing the screwing. For the "shelf" where the batteries are, just use the same length screws that you pulled out and stay in line, longitudinally, with the screws where they are now. Do that and you're 100% good.
For the new charger, you should have noticed glassed-in wood on the hull side that the charger was mounted to. Same thing - stay with the same length screws you removed.
For the new charger, you should have noticed glassed-in wood on the hull side that the charger was mounted to. Same thing - stay with the same length screws you removed.
mwph
Well-Known Member
- Jul 8, 2008
- 3,229
- Boat Info
- 1998 250 DA
- Engines
- 7.4L, B3
Dennis - I'm surprised you didn't suggest some sealant in the old holes just for good measure.
Overkill?
Overkill?
rondds
Well-Known Member
- Oct 3, 2006
- 8,859
- Boat Info
- 2001 380DA
- Engines
- Merc 8.1s (2008)...Hurth ZF 63 V-drives...WB 7.0 BCGD (2013), Garmin 8208 & 740 MFDs, GMR 24xHD dome
Definitely copious sealant. And don't overtighten. You'll get a sense of how thick the "floor" is when you drill it but you don't want to strip out the material.
Nope, not at all. I guess I figured that was a "given".
And there's the whole "chamfering" of the hole thing - but then, none of the holes that are currently there were chamfered. But that's not to say one can't do better than original. However, given the original line of questioning, I didn't want to get too technical, either.
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Thanks for the info. And don't hold back on the suggestions. I was thinking that if I knew the panel thickness, I could drill an oversize flat-bottom blind hole and put in a stainless threaded insert, potted with epoxy adhesive. But that would be overkill I think.
I think so, too. BUT, the shelf/panel thickness is not that thick, anyways. Maybe 3/16" or 1/4"? Maybe less. Not entirely sure, though, as I've never measured it. You should be able to figure it out by checking out one of the current holes that you removed a screw from.
Counter sinking/chamfering:
http://clubsearay.com/showthread.php/17850-Need-to-drill-a-hole-in-my-boat-help
