Rigging question

Thanks for the feedback, I forgot that a primer bulb includes a check valve. Interesting reason to put the primer on the tank side of the water separator - most times I see it plumbed in after. My motor is a newer Etec, and the rigging instructions actually say to not include a primer bulb - apparently the main pump on the motor is designed as a lift pump - which is great (no priming required), but seems to have lead to the annoying siphoning issue when you try to drain your water separator.
 
Thanks for the feedback, I forgot that a primer bulb includes a check valve. Interesting reason to put the primer on the tank side of the water separator - most times I see it plumbed in after. My motor is a newer Etec, and the rigging instructions actually say to not include a primer bulb - apparently the main pump on the motor is designed as a lift pump - which is great (no priming required), but seems to have lead to the annoying siphoning issue when you try to drain your water separator.
With any fuel injected engine you don't need a primer bulb between the filter and engine. Every boat with a gas engine should have one between the tank and the filter. It serves alot of purposes
 
Couple of notes:

1) When you drain the bowl on the fuel water separator, do you have room to get a container underneath? I would also mount the separator on a spacer so that the filter isn't so tight to the hull - gives you a bit of room if you need to get a strap wrench on it.
2) Here's a weird one. When I try to drain the fuel bowl on my water separator, it just drains/siphons everything back into the tank and nothing comes out the bowl drain. I looked this up, and its a fairly common problem. You might want an isolation valve on the inlet to the filter, but I'd be curious if others have experience with this
3) Lastly, both batteries are on starboard side. Captain is on starboard side. If you are running with minimum load/passengers, the boat will likely tilt to starboard. If you consider swapping the batteries to the other side, you will have a more 'neutral' setup.
Thx for the note... separator will be high enough up to get a container under it. I'll incorporate a bulb as mentioned (maybe x2 as there are 2 tanks ?)... and the batts are both located on the starboard side to offset the weight of the kicker (located on the port side). The pod follows the hull and will provide a fair amount of flotation - I am a bit concerned about the saddle tanks adding to the side-to-side instability ... but hopefully trim tabs will compensate for some of that.

Cheers, Oscar
 
Again, it’s what I like. The 316 SS clamps are awesome. Oetiker clamps are great until you have to take them off and I find the sizing annoying. As far as the width is concerned I still prefer it.

They are better lamps in my opinion
Can't agree. Fully circular clamps like Oetiker provide clamping pressure evenly around the hose. Gear clamps have a straight barrel section in them; at each end where that transitions to circular, you have an area of no clamp pressure and therefore the potential for fuel and air leaks. You may not see dripping fuel, but those little air leaks are usually the reason behind problems with motors losing prime and subpar fuel flow at WOT. Even in low pressure systems where outboard makers use cable ties, if you look carefully, the tie has a radiused section on the otherwise square moulding used to make the connection.

Gear clamps get you by for temporary work and testing, but are not intended for a permanent, in hull fuel system. That work should be treated like a utility infrastructure installation: use top quality materials and best practices, and it will be reliable and safe for decades. Use USCG A1 rated hose stock and proper crimped clamps, follow ABYC guidelines.

Oetiker clamps can be removed pretty easily with a slot screwdriver, but yes, they're a one time use item. And yes, you need to accurately size them, but it will be the same size for an entire hull fuel line job, so you buy a few dozen at same time and retain some spares. Replacing all lines at once and not mixing and matching material is the only thing that makes sense. Fuel system is too important to patch and band-aid.
 
I agree that any fuel system components installed below hull you would want permanent/stainless Oetiker style hose clamps - especially if the work was done by a professional shop. However, if you are just trying to redo the fuel lines on 12ft car-topper with a 9.9, I'm sympathetic to those that don't want to buy specialized tools. In that case, use a fuel injection hose clamp which provides the ease/re-usability of a gear clamp, and addresses the risks identified by @sly_karma

Widely available at any auto parts store - you just need to ask for them.

 
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If you want to get fancy and away from clamps all together can always buy some earl fittings - AN fittings, and just have everything tighten together instead of relying on gear or oetiker clamps. Russell also makes nice AN style fittings etc, or New-Line hose and fitting.
 
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Couple of notes:

1) When you drain the bowl on the fuel water separator, do you have room to get a container underneath? I would also mount the separator on a spacer so that the filter isn't so tight to the hull - gives you a bit of room if you need to get a strap wrench on it.
2) Here's a weird one. When I try to drain the fuel bowl on my water separator, it just drains/siphons everything back into the tank and nothing comes out the bowl drain. I looked this up, and its a fairly common problem. You might want an isolation valve on the inlet to the filter, but I'd be curious if others have experience with this
3) Lastly, both batteries are on starboard side. Captain is on starboard side. If you are running with minimum load/passengers, the boat will likely tilt to starboard. If you consider swapping the batteries to the other side, you will have a more 'neutral' setup.
I have saddle tanks in my boat and I’m not going to get into quoting TC or ABYC scripture because I implore people to do it themselves, I believe you either have or should have fuel tank shut offs at the tank that should be accessible. If I forget to close these valves on my boat the vertical column of fuel in the line will siphon all the fuel out of your plumbing. When I had my last survey done in 2021 the surveyor checked for these valves and their condition.
Also just to clarify ABYC are not regulations but recommendations. It’s only when they are referenced in TC regulations as compliance requirements that they carry weight so to speak.

I hope this helps
 
Can't agree. Fully circular clamps like Oetiker provide clamping pressure evenly around the hose. Gear clamps have a straight barrel section in them; at each end where that transitions to circular, you have an area of no clamp pressure and therefore the potential for fuel and air leaks. You may not see dripping fuel, but those little air leaks are usually the reason behind problems with motors losing prime and subpar fuel flow at WOT. Even in low pressure systems where outboard makers use cable ties, if you look carefully, the tie has a radiused section on the otherwise square moulding used to make the connection.

Gear clamps get you by for temporary work and testing, but are not intended for a permanent, in hull fuel system. That work should be treated like a utility infrastructure installation: use top quality materials and best practices, and it will be reliable and safe for decades. Use USCG A1 rated hose stock and proper crimped clamps, follow ABYC guidelines.

Oetiker clamps can be removed pretty easily with a slot screwdriver, but yes, they're a one time use item. And yes, you need to accurately size them, but it will be the same size for an entire hull fuel line job, so you buy a few dozen at same time and retain some spares. Replacing all lines at once and not mixing and matching material is the only thing that makes sense. Fuel system is too important to patch and band-aid.
You don’t have to agree with me, nor was I asking you to? I don’t tell people what to do. You can get qaulity hose clamps that are not the North American breeze garbage. Have fun with your pile of oetiker clamps. Seriously, do whatever you want. Also, ABYC is a list of recommendations not regulations and some of them I don’t agree with either. Regulations are different. So cut copy paste off the internet as you please and WOT air leaks are usually from using garden hose fuel line.

Honestly if the hose is on a proper bard the clamp isn’t doing much anyways so your circumferential clamping banter means nothing.

Peace ✌️
 
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I think you guys are over thinking it. There is absolutely no need to double hose clamp a fuel line onto a hose barb this size. Whatever clamp you use make sure it's stainless that's it. Good luck trying to pull off a proper fuel line after a while it's been clamped onto a proper hose barb. Good luck trying to double clamp onto a 3/8 barb. That's just nonsense. You'll have to cut it back to reattached it 90 percent of the time if you wanna remove it anyway, so it doesn't matter what clamp you use. This is why you leave yourself slack on any type of hose. At least enough slack throughout the run to get a few inches here or there if you need it. The clamp really is just the securing it so it doesn't move. You shouldn't be compressing it to death. Tight is tight.

The reason in the industry we don't use a metric clamp, ( well my shop sure doesnt) is because it's really frustrating when you have multiple different sizes everywhere. Stick with the most common which is 5/16 in which 8mm is basically the same at that point so they both work. Oteiker clamps are what is most widely used in fuel systems within the industry. That's the system I prefer for customer fuel systems and that's on an industrial level when I'm doing large fuel systems, and I do alot of large fuel systems. DIY do what you want just make sire it's stainless. Make sure you use good materials. No need to reinvent the wheel.
 
I think you guys are over thinking it. There is absolutely no need to double hose clamp a fuel line onto a hose barb this size. Whatever clamp you use make sure it's stainless that's it. Good luck trying to pull off a proper fuel line after a while it's been clamped onto a proper hose barb. Good luck trying to double clamp onto a 3/8 barb. That's just nonsense. You'll have to cut it back to reattached it 90 percent of the time if you wanna remove it anyway, so it doesn't matter what clamp you use. This is why you leave yourself slack on any type of hose. At least enough slack throughout the run to get a few inches here or there if you need it. The clamp really is just the securing it so it doesn't move. You shouldn't be compressing it to death. Tight is tight.

The reason in the industry we don't use a metric clamp, ( well my shop sure doesnt) is because it's really frustrating when you have multiple different sizes everywhere. Stick with the most common which is 5/16 in which 8mm is basically the same at that point so they both work. Oteiker clamps are what is most widely used in fuel systems within the industry. That's the system I prefer for customer fuel systems and that's on an industrial level when I'm doing large fuel systems, and I do alot of large fuel systems. DIY do what you want just make sire it's stainless. Make sure you use good materials. No need to reinvent the wheel.
Once again you go on with your logic and reason again ship! You make an even better referee lolz.

Night
 
Keep it stupid simple. User friendly and serviceable. How's that for logic lol.

One other thing I'll add is Oteiker clamps shouldn't be used everywhere. But in a rigging situation, let's say a primer bulb in line and a fuel line going into a rigging tube or harness, they are the best. I have a rule, if you can't easily get the tool on the clamp that clamp doesn't belong there. If you can't either wiggle it free by expanding it with a small slot screwdriver or grab the outside with some sidecutters or the pinch tool then that clamp doesn't belong there..
 
You are supposed to double clamp the fuel fill hose that fills the tank. Single clamps are fine from the tank to the motor. At least that was my interpretation
 
Fuel fills, are a totally different hose and when you start going onto a 1.5inch barb or higher you gain alot of length on the barb. Not only that but you have a non expandable hose with a wire in it. So usually the fill fittings have a less aggressive barb. Meaning that they need more support. Also that's an area where they are not exactly easily accessed so transport rules say they need to be secured in a higher fashion. They have the room on the barb so it makes sense and it's no big deal. Don't put oteiker clamps on those though lol. Gear it up
 
You are supposed to double clamp the fuel fill hose that fills the tank. Single clamps are fine from the tank to the motor. At least that was my interpretation
That is how I read it as well, that was what my marine surveyor also wanted to see as well as the clamp thickness. There’s a published table that’s easy to find.
 
Ok… zip ties n’ duct tape it is 😬.

Thx for all the info and discussion, I’m lucky to have a platform to throw this stuff out and get some good feedback. Learning to take advantage before rushing down the wrong road.

Cheers… and thanks again,
Oscar
 
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