EFLAN

I Have A 1987, 31' Formula F-311 Sr-1. I Have A Problem With Water Accumalating Under The Step Below Deck. After Cleaning Out, It Comes Back. It Is Not Coming From The Builge Area, But Seems To Be In The Front Hull. Water Tank Is Empty And Not Being Used. Does Anyone Have Any Suggestions On Where The Leak Could Be??? Any Guess????

handfulz28

Search the Formula Forum. Suspects include screws holding the windshield need to be re-sealed, water sloshing forward from the bilge, spray through the deck joint (behind the rubrail)...
Next time you drain/clean it, put a plug in the drain hole that goes back to the bilge. That will help elimnate the sloshing forward theory. Also, depending how much water gets in there, the area forward of the step, under the floor, tends to hold water and takes a few tries to dry out completely.

Prater

Pull all the screws from the windshield one at a time and add sealer to the threads. Or pull the windshield and reseal the base. My 357 has the same problem. I also had to reseal around the front lift point on the deck.

LetsGo

Is you speedometer working...
Just a hunch, check the tube going to the speedometer...

US MUSL

I had the same problem with my 1986 272 SR1. I used clear sealant any place on the windshield where there was a gap that would allow water in.

Thunder Struck

This would be the problem. Pull the windshield and reseal. I had to do it as well. '89 Formula F311.

88formula223

all good advice, another place where the gas tank comes out of the floor silicon that all the way to the bildge. like handfulz said search the Formula section its been covered many times

WARPARTY36

I had the same problem on a 223 and 272. Good to hear I wasn't the only one.

srl520

I had this same problem that started last year. I was told that it could be caused by any of the above reasons and there was more, but we have not had rain her for 100's of days(lasvegas). This is what I found.
I noticed water leaking in from a small pin hole in the front floor of the cabin. After a summer of this and shampooing and cleaning carpet, if finally is ruined. I decided I was going to have to tear into the floor and find out where it is coming from.
Under the floor is filled with foam. I cut much of the foam out and vacumed out the water. had to get everything dried out. I could not find anywhere that water could be comming in from. I should of taken the boat to the lake at this point.
I decided to fix the problem by drilling small holes at the bottom of all the stringers so that the water could drain back into the sump under the step.
I put new plywood floor in and glassed over the floor.
Took her to the lake and she still leaks water in from somewhere. Water slowly accumulates under the step.
The next step I took was to re-gel co the front of the keal, since the gel had worn thin from beaching on the sand. I was told that water can seep through the bare fiberglass.
I still have water coming in.
I think I am going to have to tear the floor up again to find out where this is coming from.
As far as your problem, not good. Once the water gets under the floor and fills in all the voids and finds a pin hole to get out into the cabin, you are screwed. There is no way for the water can get back out from under the floor.
I have pic of the whole project that I will post when I get back home.
I then had to replace the carpet. This is a whole nother post and major project that I have pic of.
I will find where the water is coming from eventully.
The only thing left I can think of is there is water under the floor where the gas tank is and it is leaking through small hole in the front bulk head. Formula Tech says there is no way water can get from the bilge through 2 bulk heads to reach under the cabin floor.
Maybe this is why my boat/trailor scaled out at 14,700 lbs and I have lost 5mph over the last year.

WARPARTY36

I thought mine might have come through the deck hatch???? Even on the trailer I had water under the step every time it rained and got tired of vacuming the water out. I never did figure it out. Sounds like one of those mysteries of life.