Yamaha F200 new hiccup

[RDJ]

Had my '03 F200 develope a hiccup the last couple of weeks I can't figure out. This motor has been a pleasure to own and has performed flawlessly for several years now but I got a fuel problem all of a sudden that is sporadic.
Two weekends ago while prefishing on a Saturday I had the motor stall on me twice due to being fuel starved when getting up on plane. I had been running the boat at all speeds all morning and still had plenty of fuel when all of a sudden when I went to make a move and put the throttle to W/O to get up on plane the boat stalled shortly after planing. It didn't die but was sputtering at idle so I shut it down and went back and checked the ball and it was flat. Pumped the ball hard and motor started right back up and acted as though nothing had happened. An hour or so later it did this again when moving but once the ball was reprimed it was normal operation. After the second time I probably ran 20-30 more miles throughout the rest of the day running at all speeds from W/O down to pulling cranks with my T8 and it never did it again. I had a similar thing happen a few years ago but it was a constant loss of fuel flow and found that the small inline fuel filter on my T8 had a cracked housing and was losing fuel system vacumn. A new filter fixed the problem. I thought the same thing might be wrong so that night I changed the T8 filter (I always pack a spare now) and on Sunday we prefished for about 6 hours without a problem so I felt confident I had fixed the problem. I went back to the lake midweek to prefish a few days before our tourney and for 3 days of hard fishing the F200 never missed a beat. On Saturday after 1/2 a day of tourney fishing including a 20 mile run or so to one of our spots we filled our limit out and decided to run back north about 35 miles to check a spot for Sunday. When I put the throttle down to leave the motor again stalled and was left sputtering. I went to the splash well and primed the flat ball hard and again the motor started up instantly and idled perfect. We took off and made a 50 minute run at 3/4-full throttle with no issues for the rest of the day. On Sunday the motor performed perfectly and never hesitated once so I am really struggling to think what could cause this intermitent loss of fuel flow? It's only stalled 3 times out of 6 1/2 days of fishinng with no pattern to this happening. The only thing I found common to when it happened is that it was during the hottest part of the day on the two hottest days we fished on. It was in the mid 90's both days. Could this be some kind of vapor lock due to hot weather? It has not done it in the first half of the day when temps are cool. I would suspect that either the F200 or T8 ball might be bad if it did if more frequently but it is so sporadic its hard to think thats it. I am tending towards some sort of vacumn leak or vapor lock as I noticed the T8 ball was also flat on two of the occasions. It's kind of a ghost but I need to chase it down before I get stranded on the water.
Any suggestions from you motor guru's?? I would appreciate any and all input or thoughts.
Thanks, RJ in Montana

[detownsend]

I had same problem on my f250. ended up needing to replace the fuel and bulb from the tank outlet to the motor. somehow it had a small air leak and the motor would lose prime. changed line and primer bulb, alls well.

[MarkG]

When you say the bulb was "flat",,do you mean collapsed?

If so, it almost sounds like either the tank vent could be partially blocked ,or the fuel line prior to the primer bulb has some sort of restriction in it. Are there any in line filters or strainer screens in the fuel tank that might need serviced? Also check for kinked or pinched fuel line going back to the tank.

[RDJ]

By "flat" I meant that the primer bulb was void of fuel. As though the source upstream (between it and the pickup) of it had been cut off or blocked and drained the line. I am kind of wondering if the check ball in the F200 primer bulb could be going bad and it doesn't close and fuel drains back into tank but it isn't noticed while running due to constant fuel flow when motor is in use. Only after stopping and shutting F200 down (fuel pump off) is this flow interupted? After this stalling within a few pumps of the bulb it was picking up fuel like normal and primer bulb would fill up to firm as normal. Weird part was it may not do it again for a couple of days. The first time it stalled it did it twice that day a few hours apart (after 1 1/2 days of prefishing) then nothing for rest of day or for the next 3 days of prefish til it did it again. After this 3rd time it primed right back up and motor fired right up and it ran fine for the next 1 1/2 days til tourney was over without a hiccup. As stated, it only did it 3 times in 6 1/2 days of fishing so it is quite random. I am assuming it is the beginning of something worse if I don't find where its losing prime or is becomming blocked. I plan on tearing into the fuel system this week, I just know how hard it is to find gremlins that happen on an occasional basis.
As far as the layout of my fuel system. I run a '03 Skeeter 1950 deepwater series. Two fuel tanks (29gal,23gal). One pickup from each tank runs into a tank selector valve in stern access. Selector valve is 3 pt. (2 "in" lines & 1 "out" line). The "out" line runs from the selector valve to a fuel/water seperator filter system (spin on filter). This filter system is also 3 pt. (1 "in" line & 2 "out" line). One out line from the filter housing runs to the F200 (with inline primer bulb) and the other out line from filter housing runs to my T8 (with inline primer bulb).
Its a great fuel system and has been flawless except for the one time mentioned in my initial post when the small plastic T8 fuel filter (under cowling) cracked and caused a vacumn leak. I tore the entire system apart several times from the tank to both motors over the course of a week before I found this. There was no sign of problem prior to the F200 stalling recently. On all 3 incidences I had either driven boat to fishing area with F200 (2 occasions) or been running my T8 (1 occasion) just prior to stalling with no issues. All seemed normal til I went to move after fishing for a while and went to full throttle and the boat would stall just as I reached plane. As posted initially, I could re-prime the fuel lines and motor would start and run as though nothing was wrong and would show no sign of problem for rest of day or even a couple days then out of the blue it would do it again. In those 6 1/2 days of fishing the motor never skipped a beat or missed (except shutting down incidences) and was ran at all throttle levels from idle to W/O and included runs of anywhere from a few minutes to 40 miles between stops and restarts.
This one is going to be a PAIN I am anticipating.. I would almost rather it just failed completely rather than this every few days thing. Its hard to find the problem if it isn't happening!! I guess all I can do is go completely through my fuel system again and clean pickup screens and replace fuel/water seperator filter and maybe change both primer bulbs and see how it runs the next time on the water.

[Tim_Kelly]

I think you might be right and the non return valve is intermittantly sticking open.

[detownsend]

Dude, don't beat yourself up on this. I had the exact same issue with my yammie f250. I spent weeks chasin gremlins from the fuel tank all the way to the motor. I know it sounds simple but start simple. Replace the line from the pickup tube and the primer bulbs, It cured my problem going on 2 years now.

[RDJ]

That is where I intend to start... thanks for the input and help..I am sure you saved me a lot of grief and time and it is appreciated..I'll let you know the results. Probably won't get to the water for a couple of weeks so won't get to test repairs til then. Thanks again..RJ in Montana

[T Mac]

Good thing it messed up...I heard you stayed put and won the tourney. ;)
You might have run away from the fish... LOL.

I know a really good Yamaha shop over in Townsend, MT... that can diagnose and fix it.
I have no idea what it is at this time, Rob.

[RDJ]

No, the motor didn't keep us close!! The fish did! Had no intention of running any farther than we did. A couple made the haul WAY south but this year we stayed above the 70 mile marker..Got smart and spent more time fishing than driving!!

[RDJ]

Good thing it messed up...I heard you stayed put and won the tourney. ;)
You might have run away from the fish... LOL.

I know a really good Yamaha shop over in Townsend, MT... that can diagnose and fix it.
I have no idea what it is at this time, Rob.

Thanks Terry for reading through it. I'll try a few simple things and if it persists I'll get a hold of Brian or Dave and see if they can take it in. Sounds like Detownsend above has gone through this already so hopefully something simple will fix it..See ya, RJ