More propane outboard questions

[john6206]

Hi Everyone - After two years of second guessing I finally pulled the string on the Mercury 5HP SailPro propane outboard. Cost almost as much as I paid for the boat - but hopefully it's more reliable than the old motor. My first impressions are positive, it's quiet, started easily, got me where I was going, no cloud of blue smoke or oil slick on the water . . . all good things.

Now I'm wondering about fuel and fuel storage. I was glad that a single 1 lb can of gas got me out to the lake and back to the marina - that was nerve wracking, the marina is not my first choice of where to run out of gas. I think I'll be using 1 lb camping fuel bottles for the rest of this season, but next year I'd like to do something different.

So my questions for propane outboard users:

What size tank do you use?
Where do you store your tank - when you are on the boat, and when you are not?
If you were going on a three day cruise - planning to sail maybe 50-60 miles, how much fuel would you bring along?

I think I'm leaning toward the fiberglass 11lb tank, taking the tank home with me when I'm not on the boat, and finding a way to secure it to the cockpit floor - just below the tiller - when I am on the boat.

Any thoughts?

 

[Jim26m]

Hopefully, you will be transporting that 11 lb tank, tightly secured, in the back of an open pickup truck.

 

[john6206]

I was planning to chain it to my bumper and drag it down the freeway.

 

[john6206]

I apologize for the snark.

It seems that there are a number of people who believe that there is no safe way to use, store or transport propane. And yet, millions of people use propane for there backyard barbecues, and generally speaking, grilling is not considered a dangerous hobby (I’m a charcoal guy myself).

I am fully aware that propane can be dangerous, but so can gasoline. if you have a motor on your boat, presumably you are burning something.

According an industry website ( don’t remember what it was called) you can safely transport up to 4 canisters of propane in a car or SUV, as long as none of them are over 45 lbs of gas.

I'm talking about one 11lb tank.

I’ll make sure it’s secured.

 

[chuckwayne]

I use a Coleman "T" adapter case that holds 2-1lb bottles. works well, gives more range as well as flow. I also can use the 4.5lb std steel tanks that Escape uses for cooking. On the 216 I lash the Coleman housing to the sugar scoop and store below when moored. I'm not impressed with the composite tanks because not only are they ungodly expensive, but they also have to be recertified every 5 years - and I couldn't find anyone that does that.

 

[Jim26m]

I was planning to chain it to my bumper and drag it down the freeway.

I guess I had that one coming... fire suppression engineer - can't turn it off.

 

[sesmith]

I bet you're really going to like that motor. We have a 2.5 HP Lehr propane outboard for our dinghy and like it a lot. We just use the 1lb cans for the dinghy, but I think your idea of using an 11lb tank is a good one. Just make sure it's stored outside or in a vented propane locker if your boat has such a thing. You may want to install an inline filter if you go the bulk tank route .

 

[sesmith]

they also have to be recertified every 5 years - and I couldn't find anyone that does that.

I had to go to a propane dealer (the kind that fills bulk household tanks) to get our aluminum tank recertified. It's an oddball size to fit the propane locker on our Catalina, so no swapping it out easily.

 

[Capt jgw]

I like the standard 20# grill tanks. They're cheap and almost every gas station in the country has an exchange setup, should be one within walking distance of anywhere you might stop. Yes, the tanks are steel and will rust, but if you're exchanging them they won't be in the boat long enough to rust much. You get a new or repainted tank every time you swap, and you'll never have to worry about recertifying them. In fact I once took an old expired tank in and they never even looked at the date, they just gave me a new one. They typically have only 15# from the exchange, I think they do that to make the price comparable to getting one filled with 20#. They say it's for safety but I don't buy that. Should be the same adapter as the 11# to fit your motor.
They won't fit most of the factory built propane lockers on boats, but if you are retrofitting you can do anything you want with the size of the locker or mounting options. I built mine to hold two tanks side by side.

 

[john6206]

I don't have anything like a propane locker on my Capri - 18. Originally I thought I could use the fuel locker - it is sealed off from the cabin, and vented at the bottom of the door to the cockpit - very near the scuppers. If you spill water in it, it drains away pretty quickly.

The actual regulations, however, say gasket-sealed top, and thru-hull drain from the locker directly to the outside - and something else I think that I can't easily retrofit into my Capri. Also, at 11.5 inches tall it's just too short for almost all propane tanks - there is an aluminum, horizontal-mount tank that would fit - but it's nearly $400 - and the locker still isn't quite right.

So I'm resolved to have this tank take up space on the cockpit floor. I think right under the tiller it won't be much in the way.
It also means I now have a relatively huge fuel locker with nothing in it. I'm sure I can find a bunch of junk to cram in there (I can always use 10 or 12 more hanks of rope).

 

[john6206]

With my gas motor, I always took way more gas than I needed on a multi-day cruise. I would typically take 5 gallons of gas on a three day cruise and when I got back I'd pour 4.5 gallons of gas into my car.

I need to know that if stuff goes sideways and I'm on the water I can get back home. I consider an fuel a safety item. So what I really need to do is figure out how many motor hours I get per 1lb bottle of fuel, and then figure out how many motor hours I'm comfortable with on a cruise.

 

[john6206]

I guess I had that one coming... fire suppression engineer - can't turn it off.

Well you have a resume, I'd be dumb not to listen to you.

Having spent almost as much on this motor as I did on the boat - I'm interested in operating it the safest way possible. I went with a Capri-18 instead of a 22 or 25 because I didn't want to buy a truck.

 

[jviss]

I built mine to hold two tanks side by side.

Wow, 40 lb. of propane! My two 10 lb. tanks last me about two years, maybe more. But then, I'm only cooking with it, it's not for propulsion.

 

[GSBNY]

Luckily my O’Day 192 has a vented fuel locker that will fit two 4.5lb steel tanks perfectly.

Worthington Steel Refillable Propane Cylinder, 4.25 lbs.

Worthington Refillable Propane Cylinder is used for powering RV appliances, grills, and other propane accessories.

www.campingworld.com

I did make the mistake of running out of propane last season because I wasn’t paying close enough attention.

 

[chuckwayne]

I have an adapter for 1lb tanks and I always carry several - just in case! the only disadvantage to propane is it's hard to know when you're running low

 

[john6206]

@GSBNY i looked at so many tanks and never found one that would fit. That one seems really close, but I bet it’s still a pinch too tall.

I bought the composite 11lb tank. Hopefully it doesn’t take up too much space in the cockpit. As a bonus, I’m sure I can find something else to cram into the fuel locker.

 

[john6206]

@chuckwayne i got the adapter and I’ve been using the one pound cans until my 11lb can comes in from backorder. I was a bit surprised by the amount of ice that forms on the can, and by the pressure when I unscrew the can.

im pretty sure one can would get me out to the lake and back, but I’ve been swapping cans before I make the return trip because I really wouldn’t like to run out in a busy marina.