Battery Tray Installation Quick Question - Ranger 520C

[gte331r]

Any warnings before drilling pilot holes for the new battery tray for the cranking battery?

Own a 2017 520C. Thanks to help here upgraded my dealer cranking battery from a Interstate 27 to a 31 X2 AGM. The battery tray was for a 27, so I've purchased a 31 size to fit the new battery.

The batteries sit on a flat, but I have no idea what is under the flat, and I can't see under there to confirm. Gas tank? Something vital? The dealer holes don't align, so I will need to drill new ones. I plan to silicone the old holes and use a little silicone as well when hand tightening the screws.

Before doing an "easy" install and drilling pilot holes, I wanted to make sure I didn't make a BIG problem but accidentally putting a hole in something that never should have a hole. Any and all advice / warnings / tips or a simple green light welcome. Any danger areas on the battery flats? Thanks!

[jc2bg]

The short answer is, don’t go farther toward the outside of the boat or use longer screws than were used originally and you’ll be fine.

[gte331r]

Thanks. BTW - Dealer only put in 2 small screws. Little surprised they have hung in there.

[sjcorpst]

Any more length than what is needed to just pierce through the bottom material is length that isn't doing anything to hold. I used four 1/2" stainless screws, the same size as what the factory put in.

[gte331r]

Any more length than what is needed to just pierce through the bottom material is length that isn't doing anything to hold. I used four 1/2" stainless screws, the same size as what the factory put in.

Thanks

I just get worried about piercing through into something else! I can't see what is underneath the flat due to the way Ranger molded the inside of my 2017 520C - total mystery. My luck I would puncture the gas tank or wiring.

[Welaka]

I just upgraded my battery. I cut the end out of the 27 tray and put a piece of foam at the end of the battery. Fits nice and tight, moves less than it ever did. I didnt want to drill holes either. I cant see it going anywhere

[gte331r]

In case helps someone else out down the road, I wanted to circle back and close loop to say I installed a 31 battery tray to accommodate new 31 sized cranking battery I bought with no problems. Previous tray was a 27 sized. Original part was a TH Marine tray, so I stuck with the same brand. But due to hole alignment, I was only able to use 1 of the original holes already in place. Drilled 3 more using 1/8” bit and carefully went just far enough to drill through fiberglass at bottom. Used 1/2” long screws - same size as used in original. Everything went fine.

Aside - it still remains a mystery what is underneath the battery flats. No way to see due to sealed fiberglass on sides going all the way to the bottom of the transom to provide no view whatsoever. There was a brief moment I wondered if somehow part of the gas tank was in play, but as best I could tell digging in forums, the gas tank is underneath the seats...? Plus I figured Ranger would have warning labels everywhere as clearly an area battery trays would be screwed in. All I can say is I didn’t smell any gas after drilling the holes (ha). My guess is that area underneath the batteries is for floatation and filled with spray foam. Just a guess (2017 520C).

[Cestratton]

Tanks are under the seat, that area is all foam unless you go INCHES and go through the hull but that'll take quite of bit of drilling.