1978 V20 Steplift trying to find leak?

BeachBum · #1 10-18-2011, 10:46 AM

I would like to start out by saying I am so thankful to have found and became a member of this website.

I just purchased a 1978 Wellcraft V20 steplift with an outboard 200hp Mercury Mariner hanging off the back. Just trailered her from Hinesville GA to her permanent home in St Augustine FL last weekend. Needless to say that was a journey both fun and scary. This is my first big boat and she needed some TLC to get moving on the trailer ie... new tires, bearing and buddies ect......

My brother and me just took her out Sunday on the ICW and she roared. just a few stall outs in idle as many people with mariners have said thats routine for this motor.

Now to my problem: When we started the day out in the AM the bow was sitting up high, nice and pretty taking on no water at the transom not even at put in. As the day progressed the bow got lower and lower and preformance was hinderd from around 40mph to about 32mph. At pull out time once the boat was on the ramp and out of the water upon pulling the drain plug atleast 8-10 gallons of water drained out. My question is to anyone that has had a similar problem could throw some advice my way on how to start the leak search process. I also want to ask about some fuel tank issues as we had to run with an external fuel supply tank being that the onboard tank is unhooked. Do you think this is because of a leak in the tank? If yes then how would one safely go about confirming that?

Thanks In Advance
BeachBum

Blue_Runner · #2 10-18-2011, 12:00 PM

Welcome to the site. My first thoughts are that 8 - 10 gallons of gas would not cause that kind of drop in performance. Water weighs in at 8 lbs per gallon so even at 10 gallons that is only 80 lbs.

Trying to find the leak - If it were me I'd probably get down under the boat and do a good visual inspection looking for cracks or gouges. Not sure of your configuration on the 78 but you might let the exterior dry completely and fill the plugged bilge with 10 - 20 gallons of water and see if you notice any dripping out around the thru hull fittings or drain plug. It wouldn't hurt to put some marine sealant around all fittings that are below the water line while your at it. The next time you take it out you can see if it made a difference.

About the tank being unhooked - where is it unhooked? Can you ask the previous owner why it is unhooked?

Wolf · #3 10-18-2011, 02:51 PM

I have a 1978 V20 cuddy, Blue Runner is correct 8 to 10 gallons is insignificant. If you have a leak it can only becoming from a pretty major crack or from one or more thru hulls.As far as the fuel tank being unhooked it is about 99% chance the fuel tank is shot. The way to check for leaks is to pressurize the tank with compressed air it should hold 3 psi for 30 min. DO NOT exceed 3psi. I replaced my tank 2 years ago. Not to bad of a job of course the foam is a bit of a pain to dig out. If there is a lot of water in the bow it would cup up the cuddy drain. I live right down the road in Daytona Bch. If you would like we to email you a few pictures of my tank replacement private message me your email address.

RWilson2526 · #4 10-18-2011, 03:27 PM

Welcome aboard....agree with the others that 10 gallons shouldnt do anything to performance....you might want to check though that you arent still carrying water in there....my boat doesnt start draining until i get it at least a 6x6 under the trailer jack stand and get it all the way up.....cant imagine that you are still carrying that much more water but its worth a look. If you noticed the boat sitting lower though I cant imagine what else it would be.

After checking the outside for the obvious get it nice and dry in there and next time you launch immediately open the hatch in the stern, lay on your bellly and get your head deep in there a with flashlight....you should either see it coming in somewhere back there or at least see it running from the bow into the back.

i4110peter · #5 10-18-2011, 08:04 PM

Welcome to the group. I have a '73 V20 Steplift. Mine is an I/O. I have always had water issues and not been able to locate source. I won't go out unless my bilge pump is functioning. I was out for the day Saturday and ran the pump 3 time to evacuate the water. I may try to find source of the leak this winter.

lathehand · #6 10-19-2011, 06:14 PM

Welcome to the site .Great choice on your first bigger boat. This is the best place to get all the info you'll need.
It may be possable possable water from storeage is trapped up under the cuddy.You may be able to look with a flash lite in the anchor rope locker and see if there is standing water.

bradford · #7 10-19-2011, 09:34 PM

Welcome to the Cult. Like others have said, I would check all the thru hulls carefully, as well as the engine mounting bolts, bow eye, livewell plumbing and if you have an access hatch in the splash well. Leaks usually don't get better with time. Glad you joined the site.

reelapeelin · #8 10-20-2011, 08:31 AM

If water was rough while you were out and doing turns, you could be taking water between the cap and hull...my old '74 separated that seam about mid ship and would get very wet turning in rough water...walk around the boat and actually try LIFTING the rub rail...I'm not saying pull out...lift UP...

Also, that's around the time Wellcraft started putting belly tanks in these boats...bow-heavy sounds like you might be getting water up front as BR and RW suggest thru a fitting and it's not draining UNDER the tank...lots of water staying up front could keep the bow down...

As suggested, look CLOSELY all under the hull along the lifting strakes for splits thru the hull...

If you have plastic thru-hull fittings that don't look bad from outside, get inside and wiggle the hose at the stem and make sure they aren't cracked at the flange...let us know how this comes out...

randlemanboater · #9 10-20-2011, 09:06 AM

If I remember right, some of the early V's had a marine head in the cabin with a through hull...am I right or just dreaming?

I'd get a handle on any water comming in before you spend much time on the water, and install a bildge pump pronto!...or at least wear your PFD.

jasoncooperpcola · #10 10-23-2011, 08:53 PM

Did you use the in floor livewell? They leak like its going out of style.

I left two screws out of a thru hull "clamshell" under the hull and within an hour the boat was limping. There was a lot of water coming thru two screw holes. And then my bilge pump wasn't working either. Turned out being a bad switch in a $150 switch panel.

To find a leak you could fill the hull with water and look for water coming out.