Lake Champlain United - Forums

I have a 9.9 Merc 4 stroke kicker with a 200 Merc ( 2 stroke) EFI main. The marina that does my work ("teed") the lines to the same tank with a lever. In other words, I can run fuel to only one engine at a time. Their logic (I believe) is that if, there was no lever (shut off), that an engine may suck air and cause major damage to that engine. The problems for me, are my kicker tends to be cold blooded until it warms up. I am essentially out of power until the kicker warms up. And also there is the hassle of going aft and switching the fuel lever to the needed engine when switching motors.
I have at least a few buddies with similar motor set ups, but their fuel lines are both active all the time. It's awful nice for them to leave the main motor running, while the kicker is warming up. This also helps them in a big wind, to just start up the main, and get their boats straightened out. They have had no issues with an engine.
I would appreciate all thoughts and help you can give me.
Thanks in advance,
Richard

Just (finally) remembered the lever or shut off I spoke of, is a swing valve in the T.
Thanks
Richard

My Yamaha dealer connected my kicker to my second output of my fuel/water separator filter and also put a shut-off in the line to the kicker. He said the Yamaha factory folks want a shut-off valve in the line to prevent the big engine pulling suction on the kicker and causing damage as it has happened in a few cases. I leave the shut-off valve always open for same reasons you speak off. If I need to operate the big motor in a hurry, I don't need to run back and open or change valves. I also often use the big motor while starting the kicker. Or in a big sudden wind (especially when playing a fish) I just might want the big engine to assit in control of my boat.

I personally don't like 3 way valves that switch between one motor or the other. I think it is an easy way to drain the fuel out of the lines to one motor or the other because you forgot to switch the valve and then you lose your prime and need to go back, switch the valve, then use the primer bulb to refill the empty fuel line before you can start that engine that ran out of fuel. In the mean time you have lost control of your vessel.

why can't you install one way check valves in each line to fix this problem?

For what it's worth, I have an Evinrude 9.9 teed off the port side tank of my boat with no shutoff and I've never had a problem. I think the only time you'd have an issue is if you ran out of gas and then the big engine could draw the fuel from the kicker, but if you run outta gas you're screwed anyways!!!

I also have a 9.9 merc bigfoot as my kicker...I placed a T in my main line and a shut off on the line going to my kicker, the only time i shut off the line going to the kicker is @ season end when i winterize the boat...never had a problem! and your right they are cold blooded so I sometimes run both motor for a few minutes to stay under power and that works fines as well.

I teed my main line passed the primer bulb to my 9.9 kicker 2 years ago. Never had a problem with either engines.
I also have a slow warming kicker, and appreciate being able to run both simultaneously when needed.
If you keep both engines in good running condition, it should not be a problem, as long as you don't run out of fuel.

Thanks to everybody for your help! These are some great ideas.
After Fishing Machine's suggestion, I called my mechanic. After a few years not being happy with the set up and as many questions about it. He finally said I could try an anti syphon valve on the kicker line, and T or Y into the main line. Kind of like what Gerry said with the addition of the anti-syphon valve. Gerry, did you T in on the motor side of your primer bulbs? BTW, I have had issues with primer bulbs since ethanol gas! Madsierra, I also like your idea of the shut off on the kicker side (and I too have a big foot) but if I leave it on, which I would, I think I would like the anti syphon option also. My mechanic is concerned for the same reasons Walt's is. Also, Gus sent me some links I will study.
Anyway, I think I have some good solutions available (thanks to you folks) that are not complicated or too expensive.
Gerry, I would like to be certain where your T's are in relation to the bulbs, using the motors for reference?
Thanks a lot.
Richard

The primer bulbs in your fuel lines to your motors actually do have check valves inside of them. That is the way they were designed to maintain the prime to the motor; but those check valves do fail often.

Anti-siphon check valve fittings are a good solution and really should be installed at the fuel/water separator filter to the fuel line of each motor. Notice I said fuel/water separator filter because I assume that every boater now has one on their boat and it also has a 10 micron filter inside it. The 10 micron fuel/water filter is the best option to protect your engines from fuel phase separation of Ethanol fuel. Yamaha requires a 10 micron fuel/water separation filter or they will not honor your warranty. They have not permitted a Yamaha dealer to install a new engine on any boat without the filter for a number of years now.

My last 3 boats have had a fuel/water separation filter installed on them since a dealer and marine mechanic that I respect and consider very knowledgeable told me to do this 10 years ago. If you don't have one, you are really rolling the dice!

Dodger wrote: Gerry, I would like to be certain where your T's are in relation to the bulbs, using the motors for reference?

The "T" is on the motor side.
I have only one primer bulb, pushing the fuel towards the "T" and into both engines.
I am using the Mercury fuel line connector on the kicker, so I can disconnect if I need to remove the kicker from the boat. It then blocks the fuel line from leaking when disconnected.
My boat is still in storage. I can take a picture of the connection when I get it out in a few weeks.
I intend to install a fuel/water separator filter this spring.

Trying to post a quick drawing layout of the fuel line.
It's coming.... Be patient....

Finally, got the drawing upload to work.

I have the same setup as Walt (Fishing Eagle), 2 separate fuel lines coming from the fuel/water separator filter but without the shut off valve to the kicker, both engines are Yamahas, and have not had a problem with this configuration.

Correct me if I'm wrong but the problem that could occur is fuel flow to both motors when running. When running both engines you could possibly starve one or the other engine of fuel. When idling both engines the big motor will draw more fuel then the kicker and could take fuel away it, the same when running the big engine at higher rpm's then the kicker. Then when running the kicker at higher rpm's so that it's drawing more fuel then the big engine at idle. In all of these cases siphoning is not a problem because the anit siphoning valves would be open when fuel is flowing thru them. Where the anti siphoning valves help is when your running one or the other engines, the anti siphoning valves will stop the engine which is running from siphoning off fuel from the engine which is not.

The things that you will want to make sure of are the correct fuel/water separator filter for your big engine to ensure you get the proper fuel flow and also the the correct size fuel line and don't forget to make sure it's rated for ethanol.

Pat

Pat... my Yammie dealer whom installed my Yamaha kicker said that Yamaha has had failures of some part inside the fuel pump I think on the small HP four strokes because the large engine when taking fuel created a suction and acted like a vacum to the part that failed. He told me exactly what part and where & what it was, but my senior memory can't reacall the particulars. He also said the failures were not that common but it does happen and Yamaha was requiring the shut-off valve to prevent it. The failure happens when the kicker is not running.

I don't close the shut-off valve to the kicker and leave it always open. After two years of operation of my Yamaha T8, I have not had any problem neither. Yet I have the required shut-off valve that will protect my 6 year warranty.

From my understanding and advice that I have heard from a number of marine mechanics, you should have a primer bulb located in each fuel line to each outboard. One reason is that the primer bulb is usually located reasonably close to the outboard with the primer bulb installed with proper direction of flow. Another reason for primer bulbs for both outboards is because small outboards usually have a smaller diameter fuel line than the larger horsepower outboards that require higher GPH fuel flow.

Plus I personally would want two seperate fuel lines, one for each eingine to give me redundancy if nothing else. If one of my primer bulbs fails or if one of my fuel lines gets plugged, I hopefully will have the other line and engine to get me back to shore. Having my kicker motor pushing me down the lake a 5 knots is better than trying to paddle to shore. Same reason I have dual batteries and redundant electrical systems. Yes I have a hand held VHF as well as my fixed radio too.

Thanks Gerry, a good drawing is worth a thousand words! As I said, I have one line coming off the T (above tank) to each motor. I am thinking that I will T into both lines, retaining both primer bulbs and adding the anti siphon valve to the kicker line. Pat, I think I understand your concerns about possibly starving a motor? I have 3/8" lines on both motors. If they are feeding off just one side of the 3/8" T, (which is all my swing valve allows) I can see this may be an issue. I have to say on a windy day, I have turned the valve over to the kicker side while starting that, and left the main motor running for a short time. The fuel line seems to contain enough fuel to keep it running for a while. I think, I may just find the needed fuel/water separator with two ports and do away with the three way valve. That may solve my problems?
Walt, I feel your pain with the "senior memory". It can be very frustrating!
Thanks again for everyone's help.
Richard