Deck plate question?

[GatorMike]

I posted earlier about water getting into my fuel tank through the fuel sending unit seal. I finally got a good tight seal on the sending unit but as a further precaution I would really like to stop water from getting through the access deck plate. I have always had a small puddle of water on top of my fuel tank even though it can no longer get into my tank I still don't like it.

So I took out the old pry out deck plate and ordered a new screw in deck plate from Amazon. I caulked and sealed it real good but guess what? She still leaks. So I put my camera inside the access with a LED light and screwed in the plate then ran a water hose over it. I'll post the video. Anyway can anybody suggest a brand of deck plate that will give me a water tight seal?

 

[mr 88]

If it's only used to check the gas tank I would put some silicon just above the rubber O ring , just enough so it does not ooze out. The only time I check out that deck plate is if I have a issue with the sending unit or gas gauge.

 

[gm280]

Could use some pipe dope and that will seal out the water but still be easily removeable. Just an idea that isn't a hardening sealer...

 

[Chris1956]

If water still leaks into your tank, sealing the deck plate is not the remedy. Water can splash onto the tank from the bilge, and possibly other places.

The tank must be sealed, and if so, sealing the deckplate is a nice to have, but not absolutely necessary.

 

[dingbat]

I have four pry out and 2 screw in deck plates. None of them leak.

To leak, you either have installation (frame) or o-ring (cover) issues.

First thing I’d try is o-ring lube. If that doesn’t solve the problem you have an issue with the installation of the frame.

The frame must be flat. Pretty common for the deck to “peak” around the cut out in the floor over time.

Install with adequate bedding material (silicon) and allow it to set a bit before snugging up the retaining screws. Be careful not to squeeze too much of material out of the joint causing the frame to warp.

 

[GatorMike]

No I have got a good seal on the sending unit now, just want to seal the deck plate as a double precaution. Later today I will try a little grease on the O-ring and tighten it down good and tight.

Like I said earlier I have the main problem cured just don't like water sitting on top of the fuel tank.

 

[Scott Danforth]

if your sending unit is leaking fumes, you have a bomb.

 

[GatorMike]

Thanks guys,
I got it to seal now. Put a little Di-electric grease on the O-ring and made a tool to help tighten the screw in lid. Doesn't leak a drop now......as for the sending unit I fixed that last week just wanted a 2nd level of protection.

 

[Grub54891]

Just a side note, if you overtighten the screws that hold the deckplate, it will warp it. Makes it leak at the gasket.

 

[Chris1956]

Mike, your fuel tank is in the bilge, right? Your bilge is not sealed, so no second level of protection....sorry.

In rough seas I have had water splash out of the bilge onto the top of my sterndrive engine, causing it to stall. The engine had a plastic water deflector over the carb, plus a spark arrestor. Water got past all of that....