Inboard engine and sail drive cockpit access hatch

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Inboard engine and sail drive cockpit access hatch

My 7.60 has an inboard Volvo Penta MD5B and 110/S saildrive. Due to the configuration of our boats, engine access has been forefront in my mind since I was first looking at mine a few months ago and nearly kept me looking for an alternative boat. There's access under the companionway stairs, but only to the front of the motor, not around it. There's also access behind the head and in the port cockpit locker, but both of those are only useful to me for visual inspections as I can't actually get my body in a good position to do any work through them. This was until I found some pictures online of cockpit access hatches that others have installed to remedy this issue.

After searching for what felt like weeks, I finally settled on a very heavy duty, all metal hatch made by Anchor Hatches. They're a Canadian company (!) who make heavy duty to very heavy duty hatches for both recreational and commercial boats. I picked it up from for the best price that I could find it for, which was about $450. That did sting a bit, but for the quality of the item that I received, I think the price was justified.

For the installation, I used a compilation of the instructions provided by Anchor, this project blog that I found for installation of a similar cockpit hatch, and my own ingenuity.

*Measure and mark out giant hole in the cockpit floor
*Cover engine with a moving blanket to keep cleanup to a minimum
*Cut giant hole in cockpit floor using an oscillating tool and a carbide blade
*Test fit
*Drill 1/4" holes for mounting screws
*Counter drill 3/8" holes through only the top layer of fiberglass
*Removed about 1/4" of core around the perimeter of the giant hole
*Filled perimeter and mounting holes with thickened epoxy and let cure overnight
*Sand everything, including flattening the non-skid where the flange will be sealed and the backside of the flange, all with 40 grit on an orbital
*Re-drill 1/4" holes through the new epoxy
*Vacuum and clean with acetone and let dry completely
*Tape off the area
*Apply heavy bead of SikaFlex 491 near the edge of the hole so it will squeeze around the corner some
*Install flange using 1/4-20 x 1.5" SS flat head machine screws, flat washers, and nylock nuts
*Remove tape and clean up

I plan on heading back tonight and will give the nuts another 1/4 turn to compress the seal while I'm starting the engine / drive work.

Before and after pics here. Sorry that I didn't take any in-process pics, but the ones in that blog that I linked above are basically the same procedure except for the choice of hardware and sealant.

Additional thoughts:
*Maintenance on the hatch is minimal. Keep the seal clean and lube it annually or when it looks like it needs it.
*I may take a grinder to the leading edge of the dogs on the hatch to give them a smoother lead in. They feel a little "grindy" when engaging now. Might just try some grease first.
*I'm definitely going to need to come up with a mat of some sort that won't hold water, because this hatch gets HOT in the sun.
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Re: Inboard engine and sail drive cockpit access hatch

Mark Williamson
Nice job! By the looks of it, and from your description, that's an essential item. Beautifully built, solid hatch.