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Random Quote: Honey... I'm going shark fishing on the breakers... Wanna come?
Find where the sending unit is in the tank by opening some of the hatches on the floor, take the sending unit out and with a pump and some containers suck the gas out.
I was not allowed to work on the motor yesterday. I was informed that I needed to step away from it for a day and do something else. Sometimes, in the grand scheme of things, this is good advice.
I will be checking the two lp vaccum operated fuel pumps next. If that doesn't find the problem, I will be ordering some stuff on the internet, mainly a fuel pressure guage, and waiting for that. It will take something like three to four work days. During that time I will be working on cleaning out the fuel tank, etc.
Don't see the need for the fuel pressure tool until your filters stay clean over time, and it still runs bad on good gas. The crud on them is stopping full pressure flow and delivery.
I would get a couple of junk yard engine gas pumps to pump the gas out into 50 gallon barrels with the hose discharge onto a paper towel over a piece of cloth to see if the crud is still coming out.
When the tank says 1/4 full I would then take the boat for a ride on the trailer on a bumpy road then immediately pump some more out with the transom pinted down hill to try to get as much crud out that you can.
Then I would not fill the tank more than a 1/4 and let the racors gets the rest of the crud while using it
Your filters have to stay clean and in our part of the world, have to be inspected an cleaned more frequently. Think old makeup brush.
The gas, well, I would burn it in the barrel as one gallon contaminates 1000's of gallons of water and you moved there cause its pristine right?
The funnel that Lude posted is the one I was speaking about. Standard 3rd world survival tool.
I would still be interested in the test with spraying gas into the intakes to rule out any ignition related problems. The original problem, or so it seemed, was ignition (plugs) I would like to know what happens with the boat up on plane and putting some fuel in the cylinders. If it picks up rpm you know its a fuel related issue, if it doesnt then ignition. Also you may have one or two injectors not hitting, and by spraying some fuel into each cylinder you could isolate which one could be giving you fits. Just an idea...
__________________ Aristocraft boats. building quality boats since 1946.
Stamas Tarpon 290 Yanmar 6lp
our problem with doing that spray test conclusively is that we need to be able to run the boat flat out. With the cowling off, and with the intake silencer off. Our water has been rough enough that if I do that I will definitely be splashing seawater all over the exposed motor. We need a flat calm day to coincide with us having the time to do the test.
I know the Contender fans will not all agree, but the boat also bounces around too much on plane in two foot chop for someone to stand back on that bracket in a 40 mph wind while bouncing up and down and accurately get hand held sprayer mist into the intakes in any kind of consistent and controlled manner. "Contender" logo on the side of it nothwithstanding, everybody on board is holding on with both hands under those conditions. Getting a squirt into one cylinder at a time is a hit or miss proposition. You are doing good to even hit the motor at all with it.
I would be out working on the boost pumps right now, except we are having some squalls rolling through this morning.
I think Gringo is on the right track concentrating on the fuel system. The behavior of momentarily achieving good RPM and then dropping back down sounds like a classic fuel flow problem. The more likely cause is going to be a flow obstruction, so the focus on filters, etc, is the right one. The less likely cause would be a bad fuel pump.
If there was a problem on the ignition side, it would probably never get good RPM, and likewise I think it would be very unlikely that a clogged or bad injector would work momentarily and drop off after a few moments.
When yer a long ways from parts, special tools and trusted dealers fer warranty service have something simple, abundent in the area you are and easy to service, (like a carbed 85 to 115 Yamadinger), or some such.
Me thinks a jet of some sort maybe worth cornsideration as well. I fished this summer in Prince William Sound, (in Alaska), and the "Copper River flats", where jets are used by most due to the shallow waters up there and the need to get close to shore to catch those wiley salmon.
Admittedly, most shallows were sand bars that didn't tear up yer hull like a coral reef would, but there were rock piles as well. The tides can also run 18 feet (which is unlikely in the tropical specs out in the ocean).
Me Brother's welded aluminum "bow picker" was 32 feet by 11.6 feet with twin fuel injected 496 inch BBChevs with 10" Hamilton jets. It took real rough water very well with lots of freeboard and would run out at 50 to 55 kts @ wot.
The real advantage was shallow water where it could go in 2" of water if on step and maybe 1 foot if just putting along on one engine.
Those big Chevys were hungry @ wot but at a 26 kt cruise @ 3000 rpm they were not so bad.
The boat could turn like a top with one in forward and one in reverse, and it could also stop on a dime as well. Very easy to get to the beach for such a big vessel.
The engines are real simple relative to the Dinger this thread is about, (but they do have fuel pump issues from time to time as well as Gubment Motors had some issues with their fuel pumps fer some reason). The fuel in Cordova was terrible too but Racors and filters seemed to keep 'em going.
Some fishermen had single engine diesels with jets that also werked well.
Dont be scared Gringo!!!! just tie a rope around your waste and get back there and squirt it!!!
yeah, today would be good. It's only blowing about 16 mph out of the SE with 4 foot waves (WindGuru) unfortunately it's also blowing rain horizontally at the moment.
I have been working to keep the water OUT of the intakes....
Oh well. We can use the fresh water. We don't get much rain here.
Well, this thing is trying to drive me nuts. And it's getting pretty good at it. Yesterday took the two boost pumps off to check them. Procedure is to squeeze fuel bulb and see if fuel comes out of the hole on the back of the pumps. They seal against the crankcase and operate by vaccum. Well, the boost pumps didn't leak, but fuel gushed out from around the o-ring on the Yamaha onboard fuel filter. After checking with the Yamaha Guru, we discovered that this filter is 28 microns. I also discovered that you should be able to tighten the ring on it all the way so that very few threads are showing. This is as far as I could tighten it:
So, since it's between two ten micron filters...and obviously warped or something, and leaking air into the fuel system, it's essentially not doing anything useful. I took it out.
Thats much simpler, don't you think? I doubt any 28 micron boulders are getting past the Racor, so who needs this there to leak?
Thinking that an air leak in the fuel system at this filter could have been causing the other issue, we filled up our five gallon tank with fresh gasoline and launched the boat again. No change. It runs up to about 5100 or so RPM for a little while ( less than a minute, something like fifteen seconds) and then gets ragged and RPM drops off to something around 3,000. And it won't go back up to 5,000 again. Until the next day.
We dumped four oz of Sea Foam in the four gallons of gas we had left, and ran around til that was just about gone. Then we tried to make another WOT run. No change.
Well, this thing is trying to drive me nuts. And it's getting pretty good at it. Yesterday took the two boost pumps off to check them. Procedure is to squeeze fuel bulb and see if fuel comes out of the hole on the back of the pumps. They seal against the crankcase and operate by vaccum. Well, the boost pumps didn't leak, but fuel gushed out from around the o-ring on the Yamaha onboard fuel filter. After checking with the Yamaha Guru, we discovered that this filter is 28 microns. I also discovered that you should be able to tighten the ring on it all the way so that very few threads are showing. This is as far as I could tighten it:
So, since it's between two ten micron filters...and obviously warped or something, and leaking air into the fuel system, it's essentially not doing anything useful. I took it out.
Thats much simpler, don't you think? I doubt any 28 micron boulders are getting past the Racor, so who needs this there to leak?
Thinking that an air leak in the fuel system at this filter could have been causing the other issue, we filled up our five gallon tank with fresh gasoline and launched the boat again. No change. It runs up to about 5100 or so RPM for a little while ( less than a minute, something like fifteen seconds) and then gets ragged and RPM drops off to something around 3,000. And it won't go back up to 5,000 again. Until the next day.
We dumped four oz of Sea Foam in the four gallons of gas we had left, and ran around til that was just about gone. Then we tried to make another WOT run. No change.
This is making me start to research sailboats.
I mentioned that way back on page 10. They have to be seated perfectly to not cause a vacuum. Any humidity or cold weather will make it expand and contract and make it difficult to put back in place. I changed my filter in december and couldnt get it back on. I brought it in the house for a few hours and went back in fitting like a glove. If the bottom of that cannister fills with enough water an alarm will sound. What did you do with the wires? Just taped them off and let them hang? Does the alarm sound with them unpluggged? What did you use to splise those 2 fuel lines together, piece of pipe? Just curious and good to know for the future in case mine fails!!!
__________________ 2006 Skeeter ZX24 Bay
2006 Yamaha 300 HPDI
2010 Ford F-150 FX4 5.4
Team: EAT-SLEEP-FISH---~ <)))))<
Trying hard to become a 1%er www.ramseydoor.com www.raynoroverheaddoor.com
I put my VOM on the water sensor to be sure it was normally open. It is. There is a little floating ring inside the filter. It floats on water. When it gets to the top of it's travel, the switch closes. I strongly suspect it's something like a magnetic reed switch. Anyhow, being normally open, it's no hassle to just unplug it and tape the connector. It's already secured pretty well.
I used a double fuel line barb to hook the two hoses together. made for splicing fuel and air lines. There is no internal pressure on that part of it.
I was just down at the local boat stuff store half an hour ago, looking for stuff to strip the bottom paint ( $ 95 a gallon?? Interstrip.) and saw a little Racor inline filter that is ten micron. If I could find one a bit finer I might stick it in there instead of the double hose barb thing.
But having a 28 micron filter between two ten micron ones is like putting chicken wire between two pieces of screen. Doesn't make sense.
I imagine Yamaha includes that initial filter for those people who operate out of portable gas cans without boat filters like the Racor or Sierra. It filters the incoming fuel for big hunks of debris, although 28 microns is still pretty small. But if you have a good filter seperator that is already finer than that....
You don't need it.
I suppose you could tap the bottom bowl of the Racor and thread that sensor into it if you still wanted a water alarm....extend the wiring, etc. Water in the fuel has not been the problem here.
I do. I put a new Racor in while I was waiting for the poppit valve parts that self destructed. That's why I don't feel the least bit nervous about taking that troublesome Yamaha filter out of there. It's for people without Racors.
I am contacting sailing schools....they have courses that in a week will get you ready to bareboat charter 42 ft. catamarans...WITHOUT HPDIs on them!!~!
Is the fuel tank vent line still clear and unplugged? Maybe the motor is creating a suction in the tank? Open the fill a little to see if there is a suction?
That's good thinking, but I have been running fresh gasoline from a Texaco station in a five gallon plastic jerry can straight into the Racor. Not using the fuel in the boat, or the boat's tank. No vent issue, the fuel line ( new) is dangling in the tank full of gas.
A yamaha micron 10 is as sufficient as a racor micron 10?
__________________ 2006 Skeeter ZX24 Bay
2006 Yamaha 300 HPDI
2010 Ford F-150 FX4 5.4
Team: EAT-SLEEP-FISH---~ <)))))<
Trying hard to become a 1%er www.ramseydoor.com www.raynoroverheaddoor.com
The little screen filter on the bottom of the VST pump is ten micron. The Plastic filter I took of is 28 micron. Since the fuel is going through a ten micron Racor before it even gets to the motor, the Yamaha twenty eight micron was not doing anything. Plus it was causing problems, swelling up. Probably due to the ethanol in the fuel. The thing was a pain in the posterior, anyhow. I kept it, if I ever need to reinstall it. But I am thinking more along the lines of putting another Racor or other 3 or 5 micron after the present Racor ten micron.
Plan tomorrow is to run out (weather permitting) and try squirting fuel in the air intakes again. But this time while running wide open.
