Throttle

[tmann45]

Some primer balls have springs on their check valves allowing them to work in any orientation, other do not.

[rodbolt17]

and
some where over the rainbow. toto got a way.

villige escapes and their primers.

[zenoahphobic]

Boscoe I just used that example for illustrative purpose. I could have used others.

Nice pictures but not much in the way of instruction of use, one example slightly up and another slightly down.

If you must argue this particular example. One , I see many bulbs in those pictures facing upwards. This convention, just like a road sign with an arrow facing upwards, but you are not literally going to drive upwards!

For academic sake, find me a bulb manufactures instruction and then I'll accept the proposition. Just simple evidence (vital evidence not implied evidence) to prove your point.

[boscoe99]

I don't have a dog in the primer ball hunt. Everyone is free to position a primer ball however they choose. Or, to not use one at all. Or, to use an electric fuel pump in lieu of a primer ball.

All I will say is that for those that are having difficulty getting their primer ball to pump fuel, they might want to try holding it vertically with the outlet on top and see what the results are.

[zenoahphobic]

Thanks that point has already been acknowledged and advice well taken.

Others are however free to enlighten me (and perhaps more importantly others) about written instructions about the ACTUAL OPERATING INSTRUCTIONS from anyone.

[TownsendsFJR1300]

+1^^^^

On every primer ball I've purchased (including the Yamaha bulb most recently installed).

**The most information posted on the packaging is the arrow goes with the flow.**.

Until these recent threads, I've never heard of the arrow having to point UP to work properly (yes Boscoe, its apparently in a manual).

With that said, mine has always worked sideways (until just worn out and replaced) for 40 years with different boats / engines.

It does make sense, having the arrow "up", but as noted, once primed, its not even needed.

[boscoe99]

Boscoe I just used that example for illustrative purpose. I could have used others.

Nice pictures but not much in the way of instruction of use, one example slightly up and another slightly down.

If you must argue this particular example. One , I see many bulbs in those pictures facing upwards. This convention, just like a road sign with an arrow facing upwards, but you are not literally going to drive upwards!

For academic sake, find me a bulb manufactures instruction and then I'll accept the proposition. Just simple evidence (vital evidence not implied evidence) to prove your point.

OK, I found this. Again, from Yamaha. Yes, they did not make the bulb but it is still their position. Right or wrong. But I am not trying to change your, or anyone's, mind. Each to do as he wishes.

I am the first to poo poo a lot of what Yamaha, NMEA, NMEA, and ABYC have to say about how things are to be done. They are not regulatory in nature and are only advisory. Follow their suggestions or not.

Yamaha is not trying to reach the 99.999% who don't have primer ball issues. They are trying to reach the .001% of their users who might, or do, have a primer ball issue.

[TownsendsFJR1300]

I don't think anyone (at least myself) does NOT believe you, its already been posted here, from a Yamaha manual, that it should point up. Obviously, up is best...

I (and I think others) just pointed out, this info is (again to at least me) new...

That's why I come here, to learn and share what I do know.

I believe that filter you have shown above is what I replaced mine about a year ago with. It is 3/8" ID, looks just like that, but I don't have the packaging anymore. I don't re-call seeing anything about the arrow pointing up (but very well could have).

[zenoahphobic]

I just having a bit of a chat not having a go at anyone.

Boscoe your last bulb reference interestingly refers to a high volume and a below deck mounting. The word "mount" I might argue is getting closer to my point, previously you showed a "connect" diagram. Neither of these two examples are "operating instructions".

And I summize from the below deck installation (as a opposed to above deck as written) that it is not meant to be hand operated much at all. This brings up the point I think Townsend made elsewhere, that the up position makes for better air removal and is probably only necessary at initial "installation" and bleeding of the system.

Interestingly, we now have an example of a bulb that probably is bigger and better suited than the run of the mill that have been around for decades, primarily serving a short portable tank to engine application. So this example in part, answers my request for a better bulb on previous other postings!
Thankyou

[RayBersch]

Now what was the OP's question? How is it the most experienced guys on this site get off into the blue shy, do circles until their primer bulb collapses and forget about the guy waiting for some help?

My experience with a self closing throttle came on a jet ski - don't know if they are all that way, but let me tell you running that thing for an hour with constant pressure on the throttle got very tiring and I never used the jet ski again. In over 50 years of boating I have never had a throttle return to idle when the grip was released - that goes for tillers and remotes. Some do notch down a bit but never have I seen one return to idle.

As for the safety question on this issue, consider running at say 3/4 power in your average size boat and letting go of the throttle - what happens to the passengers when the boat squats in the water and suddenly slows throwing them forward with no warning - or the operator? Not pretty.

Awrightay, my opinion - reconsider your desired solution to this one event and think back to what could have been done to avoid it. Were you traveling too fast in the canal? Did you fail to see an obstacle that you should have seen? If it hit the front of your boat it probably was floating and should have been observed, if it were submerged and you ran over it and it hit your motor the motor should have kicked up and not thrown you out of your seat. You may have a friction control on the throttle but I would not loosen it so much that the engine returns to idle.

[zenoahphobic]

The advice to the OP was keep the friction hold on throttle.

In Aus all jet skis have throttles snapping back to idle. Can't imagine not.

Having done some miles on jet skis throttles are either trigger finger or more common thumb push. I don't know why no twist throttles like motor cycles.

I find finger pull most comfortable but that setup can lead to dangerous feedback. I.e. Pull to quickly sending you backwards inadvertently pulling more on throttle.

Cruise control is the way to go with sensors to detect when pilot has left into the drink.

[zenoahphobic]

I never travel on a boat if I am not in charge, unless it has a canopy. Many a time found myself caught by the canopy just before flying over the bow ?

[zenoahphobic]

I've done more reading and conclude that the written instruction to mount with arrow up, is only a double check that the bulb is facing the correct way.

The fuel line travels from the tank below deck UP to the engine. Just a double check and want for neatness - nothing to do with desired orientation for operation!

[boscoe99]

I've done more reading and conclude that the written instruction to mount with arrow up, is only a double check that the bulb is facing the correct way.

The fuel line travels from the tank below deck UP to the engine. Just a double check and want for neatness - nothing to do with desired orientation for operation!

You must be from Missouri. More reading is recommended for you.

Yamaha is almost paranoid about restrictions to fuel flow. It might be that their primer balls, and their balls only, are designed such that the check valves have very slight pressure to position them closed, so as to minimize any restriction to fuel flow within the ball. Not having as much pressure as other valves might cause the Yamaha valves to be fussy when it comes to their seating. That fussiness might cause the valve to not work as well as one would hope unless the ball is positioned vertically.

Once again, I am not saying to anyone to position their primer ball vertically. I am saying that if the dang thing is not working well then try positioning it vertically and see what happens. Might work for some. Might not work for all. There is nothing to lose and there is no cost. Once the system is primed then let the ball fall wherever it may. At that point it won't matter. The primer function is no longer in use.

The MOST common problem on two strokes

Extract from the link website above is provided below for ready reference.

Orientation

It is also advantageous if the primer bulb can be position in such a way that during priming it can be oriented vertically, with the direction arrow pointing skywards. This will allow gravity and the weight of the fuel inside the primer bulb to help with the operation of the one-way valves. If the primer bulb is oriented with the flow arrow pointing downward, gravity and the weight of the fuel in the line above the inlet check valve may spoil its operation, and the primer will not work properly.

This subtle but important point—orienting the primer bulb skyward—is often overlooked in many installation, but it really helps the primer bulb to do its job. This trick was shown to me by an experienced Mercury outboard mechanic, after I complained that the new primer bulbs he had installed did not work well. The difference in results is amazing, and just by changing the orientation of the primer to vertical, its operation is much improved. In just a few squeezes it should be possible to fill the bulb with fuel.

[zenoahphobic]

Indeed no argument about trying different orientations - good advice.

But.

Your reference reading Tony Hughes, and I quote:

"when the engine is running its fuel pump produces a suction that draws fuel past the check valve. The valves are designed so that even the modest pressure of the engine fuel pump will draw fuel past them. At idle speeds some engine fuel pumps may produce marginal pressure and may not draw fuel past the check valves"

this was written before his Installation and before his Orientation paragraph where he says "it is also advantageous during priming it can be orientated vertically",

justifying this with: "if orientated downwards, gravity and the weight of the fuel in the line above the inlet check valve may spoil its operation, and the primer will not work properly".

If you use this argument it follows: if the bulb is mounted vertically, those same gravity forces from the weight of the fuel will press down on the check valve offering greater resistance to fuel flow , that somewhat counters Boscoes reference to Yamahas paranoia .....designed check valves that have very slight pressure to position them closed.

Thus the above argument does not address the need for the suggested vertical orientation for: minimal resistance to fuel flow when the check valve is OPEN

And therefore this is an argument supporting downward orientation.

Missouri indeed.