Is a fuel primer bulb legit?

[fred4936]

As I work through everything to get the boat ready, I spotted an outboard-motor style primer bulb in the fuel line between the tank and the Racor filter. Since the boat has a Yanmar diesel, I was surprised. On the surface it looks like a good idea, but it looks more like a leak hazard, although it is dry.I just changed both fuel filters (Racor and Yanmar), and cleaned the tank. Before I put fresh fuel in it, should I get rid of the bulb? Thank you in advance!

[FPNC]

Keep the bulb, they work great for filling the Racor and pushing fuel up to the engine. They can even help diagnose a bad fuel pump. The bulbs meet USCG recreational requirements. Of which there are none. ABYC would probably whine about it.

[CassidyNZ]

Have one in my fuel line, been there for years, always works, has never leaked, I wouldn’t be without it. Mostly when these bulbs give trouble it’s because of being exposed to the elements in a dingy. Down below they last forever

[Pete7]

Standard fit on lots of Peugeot diesel cars in the 1990-2000s and made it easy to bleed the fuel system after changing the fuel filter.

Pete

[fred4936]

Thank you for the responses! I will leave it in and go with it!

[a64pilot]

Do NOT keep the bulb, they get soft, burst and none are rated for below deck use. Only use fuel line approved for below deck use, don’t use fuel bulbs or automotive fuel hose.

[chrisr]

Originally Posted by a64pilot

Do NOT keep the bulb, they get soft, burst and none are rated for below deck use. Only use fuel line approved for below deck use, don’t use fuel bulbs or automotive fuel hose.

i asked my yanmar mechanic about this a while ago, and he said same thing : DON'T DO IT !

cheers,

[Jim Cate]

Originally Posted by a64pilot

Do NOT keep the bulb, they get soft, burst and none are rated for below deck use. Only use fuel line approved for below deck use, don’t use fuel bulbs or automotive fuel hose.

As one who has used a bulb below decks for many years without softening, bursting or other problems, I can't agree with your worries relative to function. Approval is a different matter, one which is of greater importance to some folks than others.

Jim

[tkeithlu]

It's a diesel system. Diesel systems have nowhere near the concern for fuel leaks because you have to get the stuff above 150 F. before it gives off flammable fumes. The same point for gasoline is -40 C or F, hence the problem. Can you come up with a scenario of that bulb failing massively without your knowing it, and then feeding fuel onto a source of heat, such as your exhaust manifold? Otherwise, if it improves your quality of life, enjoy having it.

I've spilt close to 100 gallons of diesel in my engine room, with the engine running. It was embarrassing, but only a job of pumping it into buckets and filtering it to get the rocks out before it went back into the tank. On the other hand, I've been faced with a couple of commercial fishers who tried to pour gasoline into their tank with the engine running. We're talking about two different worlds.

[a64pilot]

Originally Posted by Jim Cate

As one who has used a bulb below decks for many years without softening, bursting or other problems, I can't agree with your worries relative to function. Approval is a different matter, one which is of greater importance to some folks than others.

Jim

On Maine Sails old site he had a “hall of fail” with pictures of things gone bad, one of them was a primer bulb that had split.
Either way it’s not approved for below deck use and any survey you get for Insurence the Surveyor ought to find it and write it up. But bottom line fuel line approved for below deck use has to pass several standards to include fire resistance, I won’t knowingly install a weak link that won’t pass the burn test, fire scares me more than sinking.
For years I just used the little lever on the engine fuel pump with no issues, last year I installed an electric pump as the factory one IP installed must have failed sometime in the past, it was installed, just didn’t work, but the electric is allowed and will keep you going should the engine driven one fail, they often fail of course by dumping fuel into the oil, so if it fails like that you will have to bypass it, and having an electric already installed, you just keep on going.
Tough to do with a primer bulb

[rbk]

Originally Posted by a64pilot

Do NOT keep the bulb, they get soft, burst and none are rated for below deck use. Only use fuel line approved for below deck use, don’t use fuel bulbs or automotive fuel hose.

^^^x2 more so if your tank is higher than your line where it can siphon into your bilge. Little bit while underway is annoying but 30-100 gallons in your bilge will ruin your day, more so if it ends up in the water.

[stormalong]

I have one in my fuel system also and have read many warnings not to have one.

A couple of points:

There are diesel rated primer bulbs. Get one and replace the gasoline version. Will it mater? Probably not.

Place the primer bulb higher than the fuel tank and make it the highest point in the fuel system. Why, you ask? Because the fuel tank is vented siphoning will not happen. If the primer bulb does fail only the fuel in the primer bulb will leak out. Although diesel fuel in the engine space and the bilge is undesirable it is not dangerous and a few ounces is manageable.

[Argyle38]

Originally Posted by a64pilot

On Maine Sails old site he had a “hall of fail” with pictures of things gone bad, one of them was a primer bulb that had split.
Either way it’s not approved for below deck use and any survey you get for Insurence the Surveyor ought to find it and write it up.

Not approved by whom? ABYC? Just curious. Never heard of any regulations about it.

I have one in my system, although it is isolated from the primary fuel line path via ball-valves. I can flip the valves and use it to help bleed if needed, then close off the valves, isolating it from the main fuel line path. Makes bleeding easy.

Never heard a comment from (two different) serveyors. Maybe because it's isolated.

Got the idea from these guys who install them on what looks like fairly large and likely Coast Guard inspected vessels:

https://www.sbmar.com/articles/squee...powered-boats/

Like others have stated, I've never had an issue with mine. It's still as supple as when new, around 13 or so years ago. if the bulb is approved for gas, diesel should be no problem. I think sunlight is much more likely to be a problem with them, but not an issue in the engine room.

Definitely something to keep an eye on, however.

[Gary Mc]

Yep have been using one for about 12 years, no issues and would not be without it.
Tried the manual lever thingy on my Yanmar and could not get it to work. The bulb works great!

[Sojourner]

After nearly burning our boat down when the electric add-on priming pump decided to catch fire offshore (good times), I swapped it for a bulb. It's great. Not quite as simple as turning a key to prime, but almost, and pretty fool proof.