Water in TomCat 255 gas tanks

[Brock]

I have a 2006 (#16) TomCat and have recently ended up with large amounts of water in both gas tanks. I first noticed the problem after Tropical Storm Ernesto surprized us here on the Chesapeake with high winds and huge amounts of rain. The first time out after the storm, one engine stalled just after getting up on plane. To make a long story short, after pumping out much of the gas, filtering the rest, and emptying the water separator over and over, I realized I had taken on at least one gallon of water in the starboard tank and almost as much in the port.

A couple weeks later another storm came along and again dumped huge amounts of rain, flooding parts of VA. Anyway, this time the port tank took on at least a half gallon of H2O (I'm still getting it out) yet the starboard tank took on just a little (all out now.) By the way, the slip is extremely sheltered on a creek off the Piankatank river so there are no waves to speak of, just plenty of rain.

Until recently I was mystified about how this much water could find its way into the tanks, but I now have a theory about what is going on. First, I noticed that the vents for each tank are mounted right below the "gutter" that channels water off the gunnel so it can't enter the cockpit. Next I noticed that the surface of the boat where the vents are mounted is angled just slightly off of vertical up toward the roof of the boat. So when the vents are mounted flush on this surface, the section of pipe that extends through the hull is actually angled down toward the tanks. When it's raining cats and dogs there is obviously a small waterfall pouring off the gunnel from the water coming off the bow, the roof, etc. and running directly onto the vents. So my theory is that the water wraps around the vent and then finds its way into the 2 holes underneath, then gravity sends it down the pipe. The starboard list of my TomCat makes the angle of the pipe even steeper on the port side, which might explain why I took on so much more water in that tank during the second storm.

I checked the one other power boat (the rest are all blow boats) at my marina which has a very similar vent and it is clearly angled down toward the water and away from the tank.

If anyone has had similar problems or has any other theories about how so much water can enter the tanks from heavy rain, please pass it on. I have ruled out the obvious things like bad gas, ethynol, loose gas caps or hose connections, etc.

Thanks,

Brock

[joeC]

Brock
I have TC#1 and have been very happy about not finding any water in my fuel system. My boat does live indoors on the trailer unless it is in use. But I have had a number of boats that would pick water up through the vents while running them. The water separators are always dry when I check them they are just Mercury spin on's. My boat has been in really heavy rains a couple of inches an hour and my problem is what to do with the water in the cockpit. In heavy rains I have to push the power on to get the stern to drop in order for the scuppers to drain. There has been almost 2.5 to 3 inches of water in the back of the boat. Keep us informed about what you find.
JoeC

[Alok]

Brock:

I have Tomcat hull #48. A couple of days ago we had torrential rain and flooding. The boat was up on blocks out in the open in a boatyard getting bottom paint put on.

Yesterday, we took the boat out for an hour in rough water at a good 25 knots. There was no evidence of hesitation or stalling. However, I will check the water separators and report back. I might also try to get a sample from the bottom of each tank and see if there is any evidence of gas/water mixing.

By the way, when the boat was "splashed" at the yard, I noticed it was sitting much lower in the water than usual. There was some water in the bilge, which is not unexpected- but both fish tanks were completely full of water! There was also evidence of entry of a large amount of water in the compartment under the transom seat. My batteries are in a pan, and there was many inches of water in the pan (a weep hole will be drilled shortly)!

I am glad that the boat is back in its covered slip...

[drjohn71a]

Oh gosh... well, it looks like I am to soon get a boat that is great, except that it is not waterproof???? in rain... Maybe we should get a portable cover to leave on the boat while asea. Alok, did you mean the fishboxes in the cockpit floor were accumulating water? Did you guys get the livewell?

Also, Alok, Is that pan under the batteries there to catch battery acid? If it is, I wonder if putting a drain hole in it is wise. John

[Alok]

Dr. John:

As I had mentioned, the boat was outside in torrential rain. Both fishboxes in the cockpit filled up to the brim with water. However, one had a set of fenders in it, so the actual amount of water was much less.

The boat was about 2 inches down by the stern when launched. Pumping out the water from the fishboxes and bilge was no problem. However, if the boat had been out there longer, and the bilges filled up more than they had, could the combined weight of the water in the fishboxes and bilge push the stern down enough to have water start backing up into the cockpit though the scuppers? I don't know.

We have AGM batteries (2 group 27 starting, 2 group 31 house). Hopefully, we will never spill any acid- so the weep hole should be OK. A good thought, though.

I do have to tell you that if our experience is any indicator, you will not regret getting the Tomcat. We are having an absolute blast.

[drjohn71a]

Thanks for that last comment, Alok. I am kind of like that - if the main thing the boat does is fine, a few snags here and there is no problem. John

[Brock]

Thanks for the input folks. If I'm right about the water getting into the gas tank vents, this is a serious problem that others should be aware of. Who knows, maybe this problem is unique to my boat?

I too have fish boxes that fill up in any rain, but I don't have any problem with standing water in the cockpit. I know the water in the boxes problem has been discussed in other threads by other TomCat owners.

The only other major issue that bugs me is the water pouring over the lower half of my engine covers at below planing speeds. The dealer tried to convince me this was not a problem, but sorry, I just don't think it's right. I know the newer TomCats have re-designed engine brackets and are mounted higher up on the transom. Hopefully that has solved that issue.

Dr. John, did you say you ordered the aft steering? I hope you get it. I ordered it but was actually sent the wrong boat with a different set of options. The dealer tried to convince me I wouldn't miss it. I miss it more and more every time I go out, especially when fishing alone. The dealer did offer to order another TomCat, but after waiting for a year I just didn't have the patience to wait any longer. In hindsight, it might have been worth it, since some of the earlier flaws might have been worked out by then.

Despite the above mentioned issues, I do love the boat. It is a very versatile, capable, fun, year round, fishing/family boat. Hopefully the experiences of us "crash test dummies" who bought early hulls will help C-Dory iron out the kinks.

Cheers,

Brock

[Alok]

Brock:

Reporting back as promised:

Checked my fuel-water separators today. The fuel appeared clear with no water level at the bottom of the bowl.

That was the good news. I also found that the starboard fish-box macerator was kaput. I had used it to empty out the flooded fish box after the rain just three days ago- it was working fine then.

Didn't have time to trouble shoot it today- hope it's just a breaker or an overheat switch of some type that has popped. Oh well- gives me something to do in the morning!

[Brock]

Time for an update:

I just went down to the boat and realized there was a simple way to test my theory. I disconnected the rubber hose that connects the vent elbow to the fuel tank, from the elbow. Then I took a jug of water and poured it over the vent while holding my fingers on the vent elbow below the gunnel. I also tried pouring the water down the gunnel. Yes, the water certainly is channeled right onto the vent, but I could not get any water to come down the pipe. So for me this is sort of a good news bad news thing. The good news is that maybe my theory is wrong. The water may not be entering through the vents. The bad news is I still have a mystery to solve and I'm running out of ideas. One variable I cannot add to my test (very easily) is high wind.

I am sure that the water entered the tanks during the two heavy rain events previously mentioned. Aso, these were the first and only heavy rain events the boat has been exposed to since we got the boat in March (VA had been experiencing somewhat of a drought). It definitely did not enter the vents while the boat was underway because I have yet to take the boat out in anything resembling rough water. I know the port tank took on additional water after the second storm because I removed all the water from both tanks before the storm and it immediately reappeared after the second.

I hope I haven't raised any alarm bells unnecessarily. I'll keep scratching my head and trying to figure out what's happening. Unfortunately, at this point I fully expect that water will enter the tanks again next time we get a deluge.

Tight lines,

Brock

[Sea Wolf]

The high wind may be a factor, especially at certain angles. I doubt the two tanks are interconnected, but if they were the air pressure on the windward and leeward sides sof the boat could be diffedent enough to force air in the windward side and out the leeward, carrying water with it.

I'm also wondering if temperature or air pressure differences during the rain storm would pull anything into the tank.

Why don't you tape up or cover up with a short section of hose the vents so nothing can nter during the next storm. No water in the tank would prove that it had been entering through the vents. If so, you'll have to change or modify the vents. Why not put in a vent set up with an inverted gooseneck behind the vent so water can't go uphill and past it?


Joe.

[Brock]

Joe,

I like your suggestions. I also had wondered about temp and pressure differences during a storm and even if a syphon effect got going somehow. I did put some tape over the vents before the last rain, but it only rained lightly. Just enough to fill the fish boxes about half way! I like the idea of adding some sort of gooseneck fitting inside to stop any inward migration of water. I might go ahead and do that. May just have to wait till the next real downpour before I figure out if the vents are the culprits.

Thanks to all for your ideas. I'll update here if I learn anything new.

Brock

[drjohn71a]

Hey Brock,

Two things.... One - I am sorry to hear about the mixup on the dual station for your new boat. As you know, though, that aft station now requires the electonic Telex steering/control systems for the entire boat, so it is very expensive. I have read articles of larger craft having a portable remote control or a wired remote control working off the main helm electronic control. Having read up on that electronic system more, I feel you could rig either a remote to an autopilot, or just install the electronic Telex controls locally or by yourself. The cost is the big hurdle.

Like you, I spend most of my time in the cockpit and felt that the aft station was even more important than radar or autopilot, although I finally went for those options too.

As far as the water in fuel problem, I know this is probably not what happened to you, but... I once had a similar problem which took me weeks to figure out and fix. The water had come from the marina pump/tank system. Prob' not your solution. If the vents are the problem, I read somewhere that, using ethanol blended fuels in humid climates, you might need to cover the vents with a suction cup type thing to keep the ethanol from sucking up the water from the air and creating a water-logged level in the tank. More experienced sea ppl prob know more than I about that.

I am hoping my boat gets done on schedule with few hitches since I am planning on a cruise up the Edmonds, San Juan Island area over Christmas vacation.

good luck, John

[Dreamer]

TC owners, We have drilled two 3/8" holes in the aft corners of the fish box gutters. The boxes are sealed practically air tight and any water on the cockpit floor goes out the scupper or into the bilges where the auto pumps discharge it. The fish boxes are sealed so tight they suffer more from condensation than leakage. We pick and choose what we store there carefully.

This has worked well for us in our area. We don't get 2" or even 1" per hour rains either. I imagine once we get some camper canvas, this will be a problem of the past. Fuel filters remain clear of water. 65 hours on engines.

[thataway]

Several of us discussed this potential/problem at the Gulf Coast gathering.
THE SOLUTION is relitatively easy--and is a clam shell vent over the fuel vent. I am not sure about the water being pulled around after the heavy rains--because we have very heavy rains in Pensacola--and no problem so far. However, it can happen in heavy seas--water pushed up into the vents from the side of the boat--and I had it happen in a diesel boat.

THe clam shell shields it from the water comming in from foreward or above..

There are a number of others who have had the macerators fail. The fish boxes really need to be pumped if any water gets in the cockpit. They are not water tight, so everything I put into them, is in a water resistant container.

My engine starting batteries, are not in the battery tray anyway...so much for acid in the bilge prevention. I do get water from around the aft seat cover into the bilge. I decided to keep the full camper canvas on all of the time. Incidently I had a chance to compare a "factory" canvas for a 25 CD with the custom cover I had made--go with a custom cover! My camper canvas has the water resistant Sunbrella (costs a bit more) and has the heavy "Stratoglass" windows--fit much better and it is virtually weather tight.

Incidently my stb tank will consistantly take 10 gallons less than the port. I suspect that the vent tube is below the surface of the tank top, and is getting into the liquid gasoline--thus spurting back before the tank is full.
Most likely the vent should be foreward--which gives better venting, and less risk of fumes if using the grill. Apparently this modification has not yet been made.

[oldgrowth]