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I've just read every page of this post and visited your blog.
I am curious, what did your house cost? What does it cost to live there (minus the boat)? Are you retired or working from there? Is health care pretty much like your boat repair?
I need a change of scenery.
To build a house here from scratch will cost ya about $ 250-275 a square foot, plus or minus, depending on a whole lot of variables. you can buy an already built house for less. With these economics going on, you can probably find one real cheap if you shop around. Someone somewhere is looking to dump a vacation home they don't use much anymore, I guarantee.
Health care is kinda strange. That, and the costs of living in a place like this are a whole nuther thread.
MEANWHILE, for those following the whole troubleshooting thing here, I just got back from the boat with my new compression guage. All six cylinders were within 2 psi of each other,i.e they were either 112, 113, or 114 psi, and I went through twice.
Well within spec. Like new, I think.
After that, not having the manual with me, I just visually went over the ignition coils and wiring, and did not see any obvious damage. The mounting lugs on that bar sticking out of the coils have some salt corrosion on them, but otherwise the coils seem well sealed. I couldn't find any obvious breaks, or burnt areas.
okay, back to the tech manual, I suppose. See what's next to check.
I can tell ya, I sure felt a big internal sigh of relief when I got down to the last cylinder and the compression was the same as the first one. Whew.
Glad to know whatever is going on is something bolted to the outside of the motor.
Sorry Rabbitfish if I offended you. I did not get but about 10 hours sleep last night thinking about it...
Gringo and I have beat up one another and hopefully we can get to the bottom of his problem.
Compression test ... Remove all plugs, Remove ignition kill switch so you don't get shocked,Place throttle wide open. Depending on Comp gage ,ie threaded in or hold in,the hold in you will need La Gringa to turn over the starter.
Min press is 81 psi. It has only 6.2:1 comp ratio. generally you see around 120 psi.
Crank it over thru about 3-4 strokes. you could get numbers like 125 upper,120 mid,and 95 lower.Slightly out of tolerance.
Squirt some oil in the bottom holes. You may want to crank it up and let it warm up then do another compression test... A leak down comp test is better, Probably local light airplane mech may have one.FAA generally requires leak down.. I have a leak down and had a scored cylinder wall on #1 on old 200 carb TS,,highest right side. It hissed like a snake ,only had 65 psi.
Your PRV press relief valve outlet (poppit valve)looked awfully corroded. Yea it only produces about 3 psi,look at the flimsy outlet hose, but enough water press to fill the block and head for #1 cyl( upper right).It tends to overheat and score the most.Also the thermostat is slightly below the top of the cylinder.
Elec Mid fuel pump press can be measured at the schrader valve ( tire valve looking)
Probably ~45 psi. It is generally the same fitting for most car EFI press tap testing points.
I am sure someone on Provo has one of these.
You may have one of several fuel filters getting clog=only 3900 rpm.
Boat water sep(racor )....... small eng mounted see thru with water sensor , spin off( #15) .
Filter/strainer leaving mid press fuel pump going to hi press pump.
see all the fuel,vapor seperator 1 #18,#26 and fuel injection lists. 68f-13844 , 60v-24251. http://www.boats.net/parts/search/Ya...UEL/parts.html.
The mid press elec fuel pump inside VST /float tank is almost identical to a car.It has a
a filter on its bottom.It has similar auto safety features. ie it will only run for 2-3 seconds when key turned ON. The ECM sees the engine is not running so it shuts off. You have to turn the key OFF for > 10 sec to get another 2-3 run.Cars were designed that way in the event of collision severing full line. Fuel pressure would drop and engine quits thus the fuel pump doesn't keep running feeding the fire. However, we still see lots of EFI car fuel fires ,probably do to improper maintenance of hoses,o rings, etc.
As far as fuel goes; it mainly comes from refineries like Shell in Curacao , Hess ,St Croix.
It does NOT have any alcohol . That is added/blended to the fuel at Port Everglades /Ft Lauderdale.There ain't no more MTBE fuel. Your Z 300 only requires 87 octane.
Engine zinc anodes are located at various points. There are some small triangular ones in the blocks water passages,held in with phillips screw.Youwill see them when the heads are off. You generally need an air impact wrench. I bought some 20 years ago but have never replaced any.The lower transom suit case handle and rudder tab eat up the most.
__________________ FL Upper Keys,33 foot World Cat w controlled upper bridge,Yam F250 w mech shift and throttles
Last edited by conehead39; 08-04-2009 at 03:27 PM.
Never replaced a Yamaha TS coil,and that is a lot of hours.
However, I have never seen the coil mounting brackets rusting like yours.
You must be ingesting salt water/salt water spray into the engine.
some how you need to cure the ingestion problem.
ie raise engine ?, install an extension plate on the upper cavitation plate, go look at some other engines ,like Suzuki.or make a bracket for the upper transom well, that will shield the upward spray.
Let La Gringa run the boat while on plane and take a look see back there.
take some more photos at various tilt positions
__________________ FL Upper Keys,33 foot World Cat w controlled upper bridge,Yam F250 w mech shift and throttles
I have had several people here tell me that the fuel does not have alcohol in it, but I don't know that for certain. I think these guys can buy fuel from wherever they like, it doesn't have to come from the US. We are on the way to the US from the USVI and N.A. And there are some independent dealers here, in addition to Texaco.
We will raise the engine, I am thinking of starting at two or three holes higher.
I paid a lot of attention to the plugs today. They were wet looking, but not fouled with the baked on salt crud that was there before. and not dripping wet, just shiny wet. The two lower plugs did not look any different from the other plugs. Of course, there is a lot less seawater getting sprayed around inside the cowling with the water pressure valve housing replaced.
I think your water ingestion is more likely coming from the exhaust side, as I described above. Seems you have eliminated all other potential sources.
Could there be a crack or failed gasket or other component at the point where the exhaust exits the power head going down into the lower unit?
Can you inspect that area without removing the power head?
If you were not down in the islands, I would suggest having a shop pull the power head to take a look.
If I let any of the shops here pull the power head, I would give it 50/50 odds of ever going back together and running the same again. Someday, I will write about the people who rinsed my aluminum fuel tank out with several gallons of water after a welded crack repair, and then left the water in the tank, re-installed the tank in the hull, foamed and glassed it back in, re-installed the console, and then put five gallons of gasoline on top of the water and called me and told me the boat was ready. La Gringa, the dog, and I got about two miles offshore into Tropical Storm Olga on our way to another island, when the Yamaha started having issues with the water in the fuel tank.
I won't go into the details of getting back to the marina in 35 mph winds with an outboard that stopped running about every seventeen thousand heartbeats. I.e. every five seconds. La Gringa drove, while I worked the manual choke. Gosh, that was just SO much fun.
And then the guys responsible had this resentment attitude about having to get all the water out of the fuel lines and carbs on my 150!! And the boat yard tried to charge me for the gasoline they pumped into the tank with the water, and then pumped back out.
nah, I think I will just forget the idea of a local shop pulling the power head.
All the symptoms you describe of lack of RPM scream clogged VST filter. Very easy to check. Pull the 3 10mm bolts that hold it to the port side of the block. Remove the 10 screws holding the top to the base. Pull the bottom off (two 10mm bolts hold on two sensors to the bottom of the VST, remove those two bolts). The filter twists clockwise one half turn and releases. Be careful, the rubber spacer between the filter and pump will fall off when you pull off the filter. Let the filter dry, and hold it up to the sun. You can tell if its clogged.
These filters are a basic maintenance item. Even if not the source of your problem, it should be changed.
68F-13915-00-00 filter
66K- 14984-00-00 o-ring for VST canister
At the same time I would also change the canister filter that is connected to the top of the VST outlet hose, that feeds to the high pressure gear driven pump.
To diagnose the problem you need a fuel pressure gauge like someone already stated. The schrader valve is on top of the VST. Hook up the gauge, run the engine until the problem occurs and record the number. If you dont want to run the engine with the cover off, remove the blank plug on the port side on the lower engine pan. This plug is used in place of a trim switch on a counter rotating engine. Run the pressure gauge hose thru the removed plug hole, and zip tie the gauge to the steering hose(s).
A drop in pressure doesnt always mean a clogged VST filter. It could also be faulty fuel lift pumps. Two octagon shapes behind the VST. If the diaphragms are played, or torn, they cannot keep up with the fuel demand from the float inside the VST.
You may want to look under the cowling for evidence of water ,droplets.
see if there is a leak from the engine both cold and hot.Check it running cover off.
Go run it briefly then stop and remove the cowling.The aft part of the engine tends to get droplets
more than front. there are some apron drains. Put some water in it a see how fast it runs out.
Is the cowling to apron gasket good.
If spark plugs still have SW,then plug up the upper hoses going to the intake crankcase coolers.
It won't hurt it. It will be like a Z250 which doesn't have them.Maybe 20 less HP at WOT.
__________________ FL Upper Keys,33 foot World Cat w controlled upper bridge,Yam F250 w mech shift and throttles
To build a house here from scratch will cost ya about $ 250-275 a square foot, plus or minus, depending on a whole lot of variables. you can buy an already built house for less. With these economics going on, you can probably find one real cheap if you shop around. Someone somewhere is looking to dump a vacation home they don't use much anymore, I guarantee.
Health care is kinda strange. That, and the costs of living in a place like this are a whole nuther thread.
MEANWHILE, for those following the whole troubleshooting thing here, I just got back from the boat with my new compression guage. All six cylinders were within 2 psi of each other,i.e they were either 112, 113, or 114 psi, and I went through twice.
Well within spec. Like new, I think.
After that, not having the manual with me, I just visually went over the ignition coils and wiring, and did not see any obvious damage. The mounting lugs on that bar sticking out of the coils have some salt corrosion on them, but otherwise the coils seem well sealed. I couldn't find any obvious breaks, or burnt areas.
okay, back to the tech manual, I suppose. See what's next to check.
I can tell ya, I sure felt a big internal sigh of relief when I got down to the last cylinder and the compression was the same as the first one. Whew.
Glad to know whatever is going on is something bolted to the outside of the motor.
Not sure whether this has been suggested. Quick and dirty spark check. Run the motor with 5 sparkplugs connected, 1 disconnected. Keep rotating the 1 disconnected through all 6 sparkplug positions. If you have one bad coil, in one of the 6 test situations, the motor performance won't change despite the sparkplug not being plugged in. In all others test situations, the performance will change because you'll have two cylinders not producing. Where the performance doesn't change, that is the cylinder that you might not be getting any spark (or fuel).
What a bunch of great ideas. Thanks. I'll be trying to isolate the problem to fuel or electrical next, I think. While keeping an eye on the lower plugs especially for any further signs of water. We are also going to raise the outboard a bit, stop letting that HPDI play "Maid of the Mist", except in sea water. This stuff is caustic, caustic I tell you!!
All the symptoms you describe of lack of RPM scream clogged VST filter. Very easy to check. Pull the 3 10mm bolts that hold it to the port side of the block. Remove the 10 screws holding the top to the base. Pull the bottom off (two 10mm bolts hold on two sensors to the bottom of the VST, remove those two bolts). The filter twists clockwise one half turn and releases. Be careful, the rubber spacer between the filter and pump will fall off when you pull off the filter. Let the filter dry, and hold it up to the sun. You can tell if its clogged.
These filters are a basic maintenance item. Even if not the source of your problem, it should be changed.
68F-13915-00-00 filter
66K- 14984-00-00 o-ring for VST canister
At the same time I would also change the canister filter that is connected to the top of the VST outlet hose, that feeds to the high pressure gear driven pump.
To diagnose the problem you need a fuel pressure gauge like someone already stated. The schrader valve is on top of the VST. Hook up the gauge, run the engine until the problem occurs and record the number. If you dont want to run the engine with the cover off, remove the blank plug on the port side on the lower engine pan. This plug is used in place of a trim switch on a counter rotating engine. Run the pressure gauge hose thru the removed plug hole, and zip tie the gauge to the steering hose(s).
A drop in pressure doesnt always mean a clogged VST filter. It could also be faulty fuel lift pumps. Two octagon shapes behind the VST. If the diaphragms are played, or torn, they cannot keep up with the fuel demand from the float inside the VST.
Cory
5 star cert. Yamaha Tech.
I looked at that VST filter when I had that apart last week. I did not take it all the way off, dry it, etc. I just swivelled it out and looked through it. It looked clean to me, but it was still wet with gasoline at the time. But I coudl see through it. We're talking about the thing that is more like a strainer than a filter, right? Can I just clean that somehow? There won't be another one here in the TCI in stock anywhere.
I did not take the canister filter off the outlet of the VST. I could not figure out how to get it loose. I broke off that strange hose clamp Yamaha uses on the inlet side of that filter, and replaced it with a hose clamp. That's the point where I discovered no fuel was coming out of the VST at the time. But the other side of that filter has some kind of a metal sleeve arrangement on it, instead of a hose clamp. I messed around with it for only a couple seconds, and it wasn't immediately obvious how to get the filter off the hose. Then I cranked the engine and saw that no fuel was coming out of the VST, so didn't pay any more attention to that filter.
After all the attacks I am almost scared to offer any ideas,,,
Gringo just a thought, on my motor I have a rev limiter in the computer system that shuts the rpms down when the computer senses a warning condition, sometimes I hear the alarm sometimes not, The motor will start fine, idles fine start to get up on plane, and run fine all the way up to the limit, I think it's around the 3200 rpm mark also, after it gets to that rpm you can still push the throttle further but nothing happens.. Between 0 to that limit there are no symptoms of trouble until you hit that rpm setting. I found my problem to be a loose wire connection under my console, I guess it had come from one of the sensors..... not sure which one. Does your motor have a rpm limiter on it???
Another member also had the problem with the prv valve cover breaking on his and he said the it filled up the lower cowling while he was running and the water couldn't drain out fast enough, and after he fixrd it there were no more problems....
Again I am not trying to tell you what's wrong with yours, just offering other ideas to check..
I looked at that VST filter when I had that apart last week. I did not take it all the way off, dry it, etc. I just swivelled it out and looked through it. It looked clean to me, but it was still wet with gasoline at the time. But I coudl see through it. We're talking about the thing that is more like a strainer than a filter, right? Can I just clean that somehow? There won't be another one here in the TCI in stock anywhere.
I did not take the canister filter off the outlet of the VST. I could not figure out how to get it loose. I broke off that strange hose clamp Yamaha uses on the inlet side of that filter, and replaced it with a hose clamp. That's the point where I discovered no fuel was coming out of the VST at the time. But the other side of that filter has some kind of a metal sleeve arrangement on it, instead of a hose clamp. I messed around with it for only a couple seconds, and it wasn't immediately obvious how to get the filter off the hose. Then I cranked the engine and saw that no fuel was coming out of the VST, so didn't pay any more attention to that filter.
The filter in that clear cannnister needs to be replaced every year. There is also a water sensor in the bottom of that cannister and an will alarm will sound if it collects enough water. You just have to unscrew the black top part of that cannnister (i use a large pliars) and then pull the clear cannister down and it will pop out as well as the filter. Its a bitch to get back in place in the cold weather becuase that cannister can swell/expand but i doubt you have to worry about that where you live. Maybe you have some water in there and its limiting your RPM's???
__________________ 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 guess it's possible, and I will check it. Again. I have emptied that clear filter at least three times during all this. No signs of water in the fuel. I also got rid of the old Perko solid brass or bronze filter that came with the boat and replaced it with a new Racor.
Does anyone know the trick to getting the canister filter off, the one between the VST and the high pressure pumps? It's got this little metal sleeve thing on it and I cannot figure out how it works. I know it will be obvious once I get it off the first time, but I have twisted, pushed, and pulled that sleeve and nothing comes loose.
I guess it's possible, and I will check it. Again. I have emptied that clear filter at least three times during all this. No signs of water in the fuel. I also got rid of the old Perko solid brass or bronze filter that came with the boat and replaced it with a new Racor.
Does anyone know the trick to getting the canister filter off, the one between the VST and the high pressure pumps? It's got this little metal sleeve thing on it and I cannot figure out how it works. I know it will be obvious once I get it off the first time, but I have twisted, pushed, and pulled that sleeve and nothing comes loose.
Sorry but i thought u said that you could not get it off. I guess we are talking about 2 differrent filters!!
__________________ 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
