My just-acquired 1994 Outrage 21 has a small leak in the aft end of the fuel tank. I am about to pull the tank for replacement I am considering reducing the capacity of the new tank to 95-gallons fuel capacity from the present 125-gallon capacity---which seems excessive--because the boat has a SUZUKI DF200 and the fuel economy is almost 4-MPG on flat water. Also, I am reluctant to ever fill the present fuel tank to full.
Removing 30-gallons from the aft end of the tank would seem to have some advantages:
--less condensation
--lighten the stern coming
--lighten the overall load.
Are there any reasons to not decrease the capacity of the fuel tank in a replacement tank?
Replies will be appreciated.
1994 Outrage 21 Fuel Tank Replacement
Re: 1994 Outrage 21 Fuel Tank Replacement
If your overall average fuel economy is at least 3-MPG, having a fuel capacity of 125-gallons suggests you'd have a range of over 350-miles. Unless you really like to make long-distance jaunts in your 21-foot boat, a fuel endurance range of greater than 350-miles does seem rather large.
As for fuel contamination with water from condensation forming inside the fuel tank, I don't really believe this is an operational problem. Most boating is done in a rather confined range of temperatures. The maximum diurnal temperature change during boating season is probably not very large.
Although one can wake up on a Summer morning to find dew on the boat, that water has condensed out from an enormous volume of air above the surface on which it has condensed. I have spent many months aboard my boat, waking up in the cabin on a cool Summer morning. The surfaces of the boat exposed to open air are covered in dew but there is no condensation in the cabin. That is because the volume of air in the cabin is very limited, and does not contain enough water vapor to create dew. The volume of air in a partially filled fuel tank is much smaller, and cannot contain enough moisture to cause a problem. My belief is that most water in a fuel tank gets there by being pumped into the tank with the fuel at time of purchase or from a leak in the fuel system.
As for fuel contamination with water from condensation forming inside the fuel tank, I don't really believe this is an operational problem. Most boating is done in a rather confined range of temperatures. The maximum diurnal temperature change during boating season is probably not very large.
Although one can wake up on a Summer morning to find dew on the boat, that water has condensed out from an enormous volume of air above the surface on which it has condensed. I have spent many months aboard my boat, waking up in the cabin on a cool Summer morning. The surfaces of the boat exposed to open air are covered in dew but there is no condensation in the cabin. That is because the volume of air in the cabin is very limited, and does not contain enough water vapor to create dew. The volume of air in a partially filled fuel tank is much smaller, and cannot contain enough moisture to cause a problem. My belief is that most water in a fuel tank gets there by being pumped into the tank with the fuel at time of purchase or from a leak in the fuel system.
Re: 1994 Outrage 21 Fuel Tank Replacement
I owned a 1997 Outrage 21--the same model of boat. It had a 2003 Mercury 250 EFI engine. Average miles per gallon (MPG) was in the 1.5 to 2-MPG range. Even with that type of fuel consumption I always thought the fuel capacity was a bit excessive. I often considered reducing the fuel tank size if I ever had to replace the fuel tank.
But what would the abandoned space be used for and how would one fabricate the new configuration? It's a wet space being open to the aft so I suppose storage could be increased, but it would have to be isolated in some way. But then you have a floor deck hatch of some sort to access the space, and I do not like large floor deck hatches.
The fuel tank was fine for my period of ownership so I never had to actually make a decision on it.
I never needed 125-gallon fuel capacity, but I did burn around 70 gallons one day fishing 20 miles out and trolling all day.
So for range the large tank capacity was not useful to me but the large capacity was useful in reducing the number of times I needed to fuel the boat. Most of my use was for fishing. Most fuel docks around here open too late in the morning or close too early in the day to get fuel the morning of or the evening before a fishing trip. Filling up with the 120 or so gallons at one time gave me about three trips out the inlet for ocean fishing. I was able to fuel up at my convenience instead of trying to fit it in my schedule. So for that reason it was nice to have the extra fuel capacity.
Water in the fuel via condensation in the tank is a non concern with this boat. If your fuel fill is the same as mine it was a combination fuel fill and tank vent. The tank vent was not an open vent. The tank would vent in response to pressure or vacuum. Therefore there was no air flow in and out of the tank like a regular open vented fuel system. Keep the gasket fresh on the fuel fill and you will not have water in that tank unless other fittings or the tank are compromised in some way.
I recommend just leaving it be and replace with a like kind tank. Easiest thing to do and the extra capacity will be there if some day you choose to sell and a buyer desires the original fuel capacity.
Enjoy the boat it is a great one!
Rich
But what would the abandoned space be used for and how would one fabricate the new configuration? It's a wet space being open to the aft so I suppose storage could be increased, but it would have to be isolated in some way. But then you have a floor deck hatch of some sort to access the space, and I do not like large floor deck hatches.
The fuel tank was fine for my period of ownership so I never had to actually make a decision on it.
I never needed 125-gallon fuel capacity, but I did burn around 70 gallons one day fishing 20 miles out and trolling all day.
So for range the large tank capacity was not useful to me but the large capacity was useful in reducing the number of times I needed to fuel the boat. Most of my use was for fishing. Most fuel docks around here open too late in the morning or close too early in the day to get fuel the morning of or the evening before a fishing trip. Filling up with the 120 or so gallons at one time gave me about three trips out the inlet for ocean fishing. I was able to fuel up at my convenience instead of trying to fit it in my schedule. So for that reason it was nice to have the extra fuel capacity.
Water in the fuel via condensation in the tank is a non concern with this boat. If your fuel fill is the same as mine it was a combination fuel fill and tank vent. The tank vent was not an open vent. The tank would vent in response to pressure or vacuum. Therefore there was no air flow in and out of the tank like a regular open vented fuel system. Keep the gasket fresh on the fuel fill and you will not have water in that tank unless other fittings or the tank are compromised in some way.
I recommend just leaving it be and replace with a like kind tank. Easiest thing to do and the extra capacity will be there if some day you choose to sell and a buyer desires the original fuel capacity.
Enjoy the boat it is a great one!
Rich
Re: 1994 Outrage 21 Fuel Tank Replacement
I can think of two possible considerations before reducing the tank capacity. Resale may be affected for a buyer who intends to use the boat for offshore fishing. A good thing about a large fuel tank is that the boat can be used for a good long while between fill ups so you can buy a lot of fuel when the price is down and only enough for your short term needs when the price is up.
Butch
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msirof2001
- Posts: 86
- Joined: Sun Oct 18, 2015 11:23 pm
- Location: Southern California
Re: 1994 Outrage 21 Fuel Tank Replacement
I had a 1995 21 OUTRAGE for over 20 years. Same "great" hull for model years 1993-1997. By the way, the fuel tank for the 1993-1997 21 OUTRAGE is 122 gallons, not 125. Sorry - I'm an accountant.
In those years, four-cycle engines were in cars. Power rating for the 21 OUTRAGE was 150 HP minimum to 300 HP maximum. Typically, these were sold with single 200- to 250-HP two-cycle engines, or twin 150-HP engines if you wanted 300-HP. I had a Yamaha 200 two-cycle and got 1.5-MPG to 2.5-MPG depending on load and conditions. I felt the 122-gallon fuel tank was adequate in most cases, but when offshore fishing and in rough seas I often came back to the dock with most of the fuel gone.
In 2013, I repowered to a Yamaha F200XB. Somewhere on this site I posted mileage statistics. With a light load, I was getting approximately 4.5-MPG. One time I had several people out on an offshore fishing trip and after traveling 60-miles south and then trolling, we found ourselves headed home directly into a 20-knot headwind with short duration two to four-foot chop. I think I was an inch shorter by the end of that day. Despite the four-cycle engine--which got great performance in optimal conditions--the mileage was in the 1 to 2-MPG range in that slop and chop and with the heavy load. With bad conditions, the mileage didn't drop a little--it tanked. The heavy load dropped my mileage from 4.5 to 3.3-MPG in good conditions. I ended up going into a marina 12-miles short of my home port to get some fuel because I wasn't sure I was going to make it.
Therefore, I believe that for offshore fishing, you can never have too much fuel capacity. I would rather be prepared for when the conditions are significantly worse than expected and you need to get back to port. I think a lot of the published performance tests use optimal condition like a quarter-tank of fuel, calm conditions, little wind, no transducers protruding, horse jockeys with empty stomachs driving. Consider that the exception. Reality is you probably will need all of that capacity one day.
In those years, four-cycle engines were in cars. Power rating for the 21 OUTRAGE was 150 HP minimum to 300 HP maximum. Typically, these were sold with single 200- to 250-HP two-cycle engines, or twin 150-HP engines if you wanted 300-HP. I had a Yamaha 200 two-cycle and got 1.5-MPG to 2.5-MPG depending on load and conditions. I felt the 122-gallon fuel tank was adequate in most cases, but when offshore fishing and in rough seas I often came back to the dock with most of the fuel gone.
In 2013, I repowered to a Yamaha F200XB. Somewhere on this site I posted mileage statistics. With a light load, I was getting approximately 4.5-MPG. One time I had several people out on an offshore fishing trip and after traveling 60-miles south and then trolling, we found ourselves headed home directly into a 20-knot headwind with short duration two to four-foot chop. I think I was an inch shorter by the end of that day. Despite the four-cycle engine--which got great performance in optimal conditions--the mileage was in the 1 to 2-MPG range in that slop and chop and with the heavy load. With bad conditions, the mileage didn't drop a little--it tanked. The heavy load dropped my mileage from 4.5 to 3.3-MPG in good conditions. I ended up going into a marina 12-miles short of my home port to get some fuel because I wasn't sure I was going to make it.
Therefore, I believe that for offshore fishing, you can never have too much fuel capacity. I would rather be prepared for when the conditions are significantly worse than expected and you need to get back to port. I think a lot of the published performance tests use optimal condition like a quarter-tank of fuel, calm conditions, little wind, no transducers protruding, horse jockeys with empty stomachs driving. Consider that the exception. Reality is you probably will need all of that capacity one day.
Current: 2017 Everglades 295cc, Previous1: 1995 Boston Whaler Outrage 21, Previous2: 1974 Sevylor Caravelle 3-man liferaft.
Re: 1994 Outrage 21 Fuel Tank Replacement
msirof2001 wrote:...With bad conditions, the mileage didn't drop a little--it tanked.
This usage of tanked seemed quite interesting to me, as it talks about the fuel tank and how the level of the fuel in that container dropped quickly or tanked, making almost a nice pun. This led me to read further about the many meanings of tank as both a noun and a verb. I found this delightful and comprehensive summary of those usages:
https://www.nytimes.com/2008/04/20/maga ... ire-t.html
To get back to boating and away from language use, I recall a similar situation. We had to make our way upwind in some rather ugly waves, and the boat's fuel economy dropped to about 1-MPG. I had just bought some very expensive fuel at about $6-per-gallon, and the thought occurred: it is costing me $6-per-mile to move this boat, a figure that seemed excessive considering the modest size of the boat.
Re: 1994 Outrage 21 Fuel Tank Replacement
Thanks all for the input on my plan of tank size reduction.
Jim: thanks for the "Getting Tanked" article. I'm feeling like the boxer who has given up and take a flyer onto the canvas--well not quite yet.
Turns out this large (122 gallon) tank was not well enough supported in the bilge. It was resting on 1/2-inch-thick rubber strips placed at two-foot centers. In three of those bearing points the fiberglass was cracked and displaced. Needless to say a fine spot for water intrusion.
I have the bow up high and thru hulls opened up and few holes drilled in the bilge to shop-vac water out. Hoping to dry it out as much as possible this winter, make the glass repairs, and hope for the best.
Any advice on prepping the bilge area for fiberglass work?
I'm concerned about the gas and oil tainted surface being a problem for bonding with new resin, either epoxy or polyester.
Jim: thanks for the "Getting Tanked" article. I'm feeling like the boxer who has given up and take a flyer onto the canvas--well not quite yet.
Turns out this large (122 gallon) tank was not well enough supported in the bilge. It was resting on 1/2-inch-thick rubber strips placed at two-foot centers. In three of those bearing points the fiberglass was cracked and displaced. Needless to say a fine spot for water intrusion.
I have the bow up high and thru hulls opened up and few holes drilled in the bilge to shop-vac water out. Hoping to dry it out as much as possible this winter, make the glass repairs, and hope for the best.
Any advice on prepping the bilge area for fiberglass work?
I'm concerned about the gas and oil tainted surface being a problem for bonding with new resin, either epoxy or polyester.