Seapro 2003 22’ WA Fuel Tank Capacity

[gpag]

This is a follow-up I posted regarding some engine problems I was having. I thought my 2003 Seapro 22’ walkaround had a 104 gallon fuel tank and have been operating using that capacity. While getting the engine issue fixed I discovered that the tank was almost empty. I expected it to have about 70 gallons. When I filled it up today the tank only took 45 gallons.

Does anyone else have this boat? What is the fuel tank capacity?

[freezerfiller]

According to RNR marine's website, it should have a 105 gal tank.

[gpag]

Anyone know how the vent line runs on this boat? I need some help clearing the vent line
I removed the vent cover and tried blowing into the vent but it seems blocked. When I take the gunnel plate off I can see the vent hose where it connects to the thru hull but can’t see how it runs and where it is attached to the tank. I’m assuming that gas is blocking the line. There as no debris in the vent cover. Would blowing compressed air through the vent clear it? Any ideas on how to fix this?

[gnrphil]

There will be an access plate of some sort at the front of the tank, I'm not sure where it is on a WA. You will see the fill and vent pipes there, should be straight across from the fill and vent ports on the gunnel.

[gpag]

When you say front of the tank, do you mean bow or stern end. There is a plate under the batteries to get to the pickup.

[gpag]

Aug 14, 2019 6:35:06 GMT -6 gpag said:

When you say front of the tank, do you mean bow or stern end. There is a plate under the batteries to get to the pickup.

Re-reading your reply, I know the access point you mean. Is it ok to blow compressed air through the line from there back to the tank?

[tigerhead]

I don't think I would risk blowing compressed air into the vent hose. Blowing toward the tank could have an undesirable result.  I've heard of everything from someone blowing a mud dauber nest into their tank, to blowing the hose loose from the tank, to rupturing the hose or even the tank. Those tanks aren't designed to take much more than static head pressure.  If I could get the vent hose loose from the tank, and blow from the tank to the vent outlet, then I might consider using compressed air.  

Harbor Freight sells a nylon electrical fish tape that would probably navigate the majority of your vent line. May not make the turn into the tank, but it would give you some idea where your blockage might be. Or if you have some heavy duty weed eater line laying around, you could use that to probe the line. 

[freezerfiller]

I think the weedeater line is a good idea. It probably is a mud dauber nest or something similar. It's probably not far from the vent so if you can disconnect the hose from the thru hull. I don't know if your vent has a p-trap in it, but that might also be the cause. mine looks like this.. www.amazon.com/Attwood-Corp-16711-TANK-P-TRAP/dp/B002IVAFYA/ref=sr_1_4?keywords=attwood+fuel+vent&qid=1565799644&s=gateway&sr=8-4

[freezerfiller]

Aug 14, 2019 6:35:06 GMT -6 gpag said:

When you say front of the tank, do you mean bow or stern end. There is a plate under the batteries to get to the pickup.

There should be a tag right near your sending unit/pickup that states the tank capacity.

[tigerhead]

Freezerfiller,

If his vent looks like the one you linked, I wouldn't think a mud dauber could get in there.  You mentioned a pee trap.  Is that a pee trap, or is it a ball check?  If it's a ball check that would explain why he can't blow back through the vent.  

[gpag]

This isn’t a new problem. I believe it was an existing issue when I bought the boat that wen undetected until now.

I have the same kind of vent as you freezerfiller. I think I found the problem. The vent hose appears to sag, allowing gas to pool in the line. I’m thinking that if I shorten the hose at the vent I can get it to run more vertically and eliminate the sag. What do you think? If I did that, would have he gas run not the tank.

[gnrphil]

At this point I would first disconnect the hose from the vent and blow some air through from the hose side to see if the vent is blocked, does fuel exit the vent when you're filling up ?
Could we see a picture of the boat on the trailer while hooked up to your tow vehicle please.

[gpag]

I took the vent off the hose and tried to blow into the hose. Lots of resistance and fuel bubbles out when I stopped. Reassembled the vent and went to see if I could add anymore gas. Gas quickly came out the fuel hole, not the vent. The photo shows the boat on the trailer at the station.

[gnrphil]

OK that looks good, obviously there's a blockage in the vent. I find it hard to believe the the vent hose is blocked, I'd suspect the vent itself. Remove that and stick the hose through the hole and try to fill, it should make no difference if there's fuel in the line as it should be pushed out, that's what mine does and I've never had fuel blow back out of the fill port. Unless it's kinked somewhere of course but I'm sure you may have seen that by now.

[gpag]

When I had the vent off I blew through it, there was zero resistance. I can’t imagine the fuel line is kinked as I was able to put in 40 gallons.
I want to make sure I understand how a vent system is supposed to work. As the fuel enters the tank from the fill hose, air in the tank is displaced through the vent, making room for the fuel, correct?
The way a boat sits on a trailer, when the fuel enters the tank it would run to the back of the tank, the low end, meaning that the vent hose would need to be attached at the other end of the tank, the high end, so that it doesn’t get blocked by the incoming fuel until the tank is full. Is that correct?

If the vent hose is attached to the front of the tank I don’t see how I could get to it.

[gnrphil]

That is correct, I would be surprised if your tank differs from mine, on mine the fill and vent are at the front of the tank (facing the bow). One would assume (which isn't always a good thing) there would be access to said fittings, I don't know where said access is on a WA model. Is there something where you step down into the cabin maybe ?.

[gpag]

I have been cross posting this issue on “The Hull Truth” to get as much feedback as possible. I have to say, with the exception of gnrphil who posts this n both sites, you guys are the better source. For this issue anyway. The last THT suggestion was maybe the tank is full.
I went out today and used about 7 gallons. Later , I’m going to remove the vent, pull the hose out the hole to make more of a diagonal to the tank and see if that helps.

[gpag]

Ok, so that didn’t work. I pulled the vent off the hose and pulled the hose up through the access hatch as far as Water I could. I blew into the hose and som gas came back. At the station, T started filling very slowly but gas came out of the vent hose after a few seconds. I then used the tongue jack to raise the bow so it had a higher angle to make sure whatever gas in the tank flowed to the back; no change.

Tomorrow I will pull the back tank access plate under the batteries and see if I can see where the vent hose connects. If that fails then it has to go back to the shop.....unless anyone has any other ideas. This seems like it wold be an easy fix, if I had access.

[Juan]

I just read this so I'm commenting late. Maybe I need to re-read the thread cuz I'm not sure I understand what's going on. Is it hard to add fuel without it gushing back out of the fuel fill port? Have you checked the fill and vent lines for crimps?

[gnrphil]

Ok so fuel is coming out the the vent hose, good it's not blocked. If fuel will go into the fill hose and come out of the vent hose I only see two possible reason why it won't take much fuel.
1, the boat is bow down and not level trapping air at the rear of the tank thus not allowing fuel to completely fill the tank. Although boat looked OK on the trailer.
2, Gas tank is in fact full.
It's a simple system unlike modern boats with the new EPA crap, there's really not much to go wrong.
FWIW I prefer this type of vent, www.amazon.com/Seachoice-18561-Degree-Thru-Hull-Connector/dp/B0064MURL0/ref=asc_df_B0064MURL0/?tag=hyprod-20&linkCode=df0&hvadid=343985504572&hvpos=1o22&hvnetw=g&hvrand=11910793838310702375&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9011267&hvtargid=pla-783064120256&psc=1&tag=&ref=&adgrpid=69358348055&hvpone=&hvptwo=&hvadid=343985504572&hvpos=1o22&hvnetw=g&hvrand=11910793838310702375&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9011267&hvtargid=pla-783064120256