OX66 Problem

[dunepray]

UPDATE:
Guys this is the exact same thing I went through with the fuel lines.

http://www.thehulltruth.com/boating-...-4000rpms.html

The same fuel line Made in Canada. The inner lining wads up when you push the connectors in. Find something else.

I just came in from running her in the yard and don't seem to have any fuel issues any longer. I've got to get her on the water. The only thing that continues is a small surge from time to time. I had played again with the idle, which had been at 600 RPM and seemed to run fine. I re-set to 700+ and then it would surge to 1200, then back to around 1000 RPM. Manual says it's supposed to be at 730 +/- 30. Do you think I should have left it alone, or does it sound like something else is the issue with the surging?

Dune

Dune

[bajakeith]

surge

possible craked reed valve or intake leak..to ck for reed watch at idle for spit back and you can also place a playing card in front of intakes also with the air box off and look at the reaction.....for intake leaks,, carb cleaner with the red nozzle 0n starting from the bottom working (spraying) up...if speed increases theres you intake leak...nothing new,,nothing fancy !!sounds like your getting her close...good luck !!: PS...did ya check the TPS ??

[TownsendsFJR1300]

Just a quick note re ethonol fuel.

I was running ethonol fuel several years ago and was doing basic maintainance on my F150. I noticed some crap in the Yamaha filter at the front of the engine, I cleaned it out and started hunting as I hadn't had any issues before.

What puzzled me (and lead to the issue) was how this crap got past the transom mounted filter as large as it was. A bit more looking and I found the inside of the fuel line from the transom filter/primer, to the Yamaha filter. The innerds literally broke down into many pieces. You could pick/pull the actual inside out of the fuel line..

Luckily I got it before it got farther. I replaced all the fuel lines with marine grade fuel line and a new primer valve (as I didn't know what was left in the valve).

Since going to non-ethonol fuel, NO issues.

Another note, ethonol related. The Yamaha fuel cup expanded and would not go back into the upper mount. The dealership swapped cups under warranty and stated it wasn't unusual, the new one slipped right in!

BTW, that cup/filter wasn't fully seated. I didn't find it until the boat died going out in a canal. Priming the bulb showed where it was leaking fuel/sucking air.... (I had been about 15 miles offshore with the filter like this-engine ran fine!).

[dunepray]

Hello Again Keith and Townsends,
No, I didn't check the TPS this time, but when I get to her today I will. I have not noticed any spit back from intakes in the past. I have noticed a small amount of oil on the lower part of the throats, but assumed this was normal. I don't understand yet what a reed valve does in the intake. I look at the parts schematics at Yamaha, but so far nothing. I'll try to research for understanding. Doesn't look like an easy fix, if cracked. Keith, by spraying carb cleaner into the intakes, how does this tell you there's a leak. I would think that by spraying it would increase RPM's anyway due to the increase in combustibles into the engine. NO??? Anyway, hope to get to the bottom of it.

Townsends, ethenol fuel will never again touch a boat I own. My last boat had an E-tec motor, and ethanol fuel gummed up fuel lines, fuel pumps, and made a mess of it. The cost difference between ethanol and regular Rec-90 is about 50 cents a gallon. On a normal days fishing that breaks down to about $10-$15 difference in fuel. When you look at the cost of maintenance and repair (and your time) associated with what you saved in cost of fuel, there's no comparison. I've had charter captains say that as long as you keep going out regularly and running fuel through the motor like your car that you will be fine. I'm not willing to take that chance any longer. And, I've now checked the motor mounted fuel filter and O-rings several times with no leaks noted. So far, so good.

Thanks All,
Will Update,
Dune

[rodbolt17]

don't get bent up with reeds.
in the past 14 yrs of working with 2 dealerships I have seen 4 broken reeds.
2 on the 3 cyl and two on the two cylinder.
all were commercial and all were due to worn down props allowing engine overspeed.

oil in the throat is normal, its called spit back and its also why there is a drain hose from the air box to the intake area.\

for every 2 or 3 cyl motor I work on I probably work on 10 EFI/HPDI v6's.

I dislike little motors and prefer V6 or at least V4 or inline 4.

don't get me started on the V8.

[bajakeith]

reed valves

Rodbolt has seen more than me on reed valves as I have only found two and were both due to water ingestion...and you spray the carb cleaner on the outsides and throttles shafts when looking for vacuum leaks..do you have the blinky light for your oxxy ???

[TownsendsFJR1300]

Just an FYI, "Reed valves" are basically very flexible plates (with a stopper to limit their opening) that acts as an "intact valve". Their bolted at one end to the block, the other end literally moves open and closes depending on the crankcase pressure.

With the carb in the lower end of the engine, when the pistons moving upward, it creates a vacuum down below in the crankcase which opens the "reeds" and allows the engine to suck fuel/air from the carb.

As the piston comes down, (positive crankcase pressure), it closes and the piston pushes the mixture charge thru the ports (holes) in the cylinder walls up to the combustion chamber. There are "stoppers" to limit the reeds opening amount...

Reeds generally give the best performance (as they open when needed and close on their own) vs piston port or a rotating disc, opening (carb on the side of a motorcycle engine-the disc has a set opening and closing spec).

[ausnoelm]

I have just read this entire saga from start to finish (again) I think the time has come to take it to someone who knows what they are doing, you are getting fixated on certain things and fooling around with bits here and there, that method usually does not fix the problem, but it can empty your wallet, and introduce a lot of new faults.

[dunepray]

Hello ausnoelm and all,
FINAL UPDATE: No Worries. At least for now... )
I think I got it. I was still losing a little pressure at the ball, and she started surging again. Couldn't figure it out at first. Pulled all the fuel lines again and I physically blew back on the main tank line and it was good. Then, blew back on the outbound side of the water seperator. Not good. I could feel a leak. Then I pulled the Racor water seperator. Guess what? The dang seal around the top of it had a crack in it. I've never seen that happen before. I had just bought a new Racor a short time ago. I had to buy a new filter at West Marine because they don't sell just the seal. Took the seal from the new one and replaced the old one. Got it all back together and she fired right up. I put all the test harnesses on her again. TPS was set perfect. O2 the same. The blinky light was giving me a 33 at first but after the engine warmed, cleared itself up. I think I'm good to go. AND, you are absolutely right, that with all the messing around I've been doing, I'll be a lot better prepared to handle anything out on the water, if something goes wrong.

Someday I hope to be able to help someone like you guys have. I hope you know by now that I don't give up on problems. I WILL WIN!

Tight Lines,
Dune

[bajakeith]

w/s seal

always install a new filter with oil on the seal !!

[TownsendsFJR1300]

Hello ausnoelm and all,
FINAL UPDATE: No Worries. At least for now... )
I think I got it. I was still losing a little pressure at the ball, and she started surging again. Couldn't figure it out at first. Pulled all the fuel lines again and I physically blew back on the main tank line and it was good. Then, blew back on the outbound side of the water seperator. Not good. I could feel a leak. Then I pulled the Racor water seperator. Guess what? The dang seal around the top of it had a crack in it. I've never seen that happen before. I had just bought a new Racor a short time ago. I had to buy a new filter at West Marine because they don't sell just the seal. Took the seal from the new one and replaced the old one. Got it all back together and she fired right up. I put all the test harnesses on her again. TPS was set perfect. O2 the same. The blinky light was giving me a 33 at first but after the engine warmed, cleared itself up. I think I'm good to go. AND, you are absolutely right, that with all the messing around I've been doing, I'll be a lot better prepared to handle anything out on the water, if something goes wrong.

Someday I hope to be able to help someone like you guys have. I hope you know by now that I don't give up on problems. I WILL WIN!

Tight Lines,
Dune

The EXACT same thing happened on my neighbors 20 CC with the 200 yamaha. And he did use oil on the filter gasket installing it. His died while we were out on it fishing. I got to sit in the rear of the boat pumping the primer bulb to keep the engine running until we got home. NOTE, his filter (with water separator) was partially exposed to the Florida sun for part of the day, I suspect the heat and time, just broke down the rubber seal...

BTW, I currently have a water separating filter hung on the transom(as previously posted). Obviously there are TWO rubber gaskets, one for the filter to housing, the other, for the see thru to filter.

When I upgraded the filter, (the old one had low hours) I saved the standard, cartridge filter, drained it, then stored it in a Zip lock bag as a spare I keep under the console. Should I spring a leak, the plastic crack, (or have an issue), etc, spin off the old, spin on the spare..

[dunepray]

ANOTHER UPDATE:
Well guys, it seems that problems still exist. I've had the engine running fine for awhile, but it seems to eat Low Pressure Fuel Pumps like popcorn at the ******. I've been through 6 since August and can't figure out why. When they are working right, the motor runs fine. When I'm between 4300-5000 RPMs I can feel it when one of them goes. I lose a few hundred RPMs immediately. When I get in I immediately pull all three and invariably one will be leaking. Not from the back (block side), but always from the front two seal and bladder. The bladder is not torn, and all the leakage is coming from around the screw holes where you can see the torn rubber. Has anyone experienced this before? HELP

This link will open photo of what I'm talking about.
XFINITY - Email currently unavailable

TIA
Dune

[rodbolt17]

are they Yamaha pumps?
what is the pump part number?

[dunepray]

LPFPs Keep Failing

Hi Rodbolt,
Sent you PM.
2002 OX66 SX225TXRA
6E5-24410-03-00 LPFP Part #
6E5-24435-00-00 Gasket
6E5-24471-00-00 Diaphram

Always OEM
Thanks
Dune

Rod,
Just thinking. I'm wondering if I have a timing issue with motor that causes a sneeze, and thus overpressure to pop these LPFPs. I've done Sync & Link (all throttle plates closed), set TPS (with throttle arm off #1 throttle body), then set idle. In the recent past I've had issues with rough idle and surging which I can now say were from LPFPs leaking. I didn't learn this until after I pulled them and found front seal leaking. Replaced with new LPFP and problem fixed. Then I would try WOT and pop another LPFP.

[rodbolt17]

ign timing wont cause a lean sneeze.
lean A/F mix in the crankcase will or excessive combustion gas blowby past the rings.
have you tried a cyl leak down test?