ok , got my oil problem solved with check valve, thanks for all the replys. when i am ready to blast off and go to full throttle i have about a 1 -2 second delay , and after i have fished for a while sometimes it may have a 4 -5 sec. delay. i have changed the filter and it is still doing it. could this be from the ethonal . filter looked fine but it really feels like it starves for fuel on take off. after it is up and running it has no problems. thanks for any advise.
2018 Skeeter FX20
Yamaha 250 SHO
Delay could be due to the prop that you are using? Please provide specs. I have the same motor on my Stratos Magnum 21XL and there is minimal delay. If you are using a prop requiring "vent plugs" then that might be the problem? Have read of well documented problems with Ethanol due to fuel line deterioration, but generally the restriction seems to be on the top end. If you have not replaced the fuel lines from the tank to the motor with the newer "Ethanol" resistant lines, then that is a great place to start. Don has documented the performance degradation issues due to the ethanol fuel. Would be wise to change the lines and bulb to up to date Ethanol resistant. JMHO though. Might also want to make sure that the fuel line bulb is "solid" after motor has been started and continues the same throughout the day. Just a few thoughts. More experienced Techs(I am not one) will also help out I am sure. Good luck.
thanks for the reply, i dont think it is a prop issue b/c the rpm's will not build up . i saw the post on the fuel lines . i am going to start there and see what happens. also i did not think about the primer bulb . i have only had this boat 3 weeks, this may be a stupid question , but do i need to prime it up before running. this is my first merc ! i had yammi's before . i love this merc , extremely strong!
2018 Skeeter FX20
Yamaha 250 SHO
Yes. Make sure that you prime the bulb before starting the big motor. I have been lazy in the past(shame on me) by not priming the bulb and the motor would stall. Always a required good idea to prime the motor with fuel. If you have any more specific questions about the motor, we have a great bunch of knowledgeable guys on this board who own the same motor. Killr Bee(SP?)(Richard) is the resident Guru IMHO when it becomes a question about mods. Good luck. Great motors IMHO.
thank you , this could possibly be alot of my problem! i will still replace the fuel lines as this upgrade was not done. thanks again!
Modified by ccole at 5:34 AM 8/8/2010
2018 Skeeter FX20
Yamaha 250 SHO
Stay with the Mercury OEM parts, I prime my 01 250xb at launch and it is good for the rest of the day.
If the prop is not vented properly or is too big--in the summer heat especially 95+hot and hi humidity---they will not build rpms quickly-- they gotta breath to turn up R's. Full tanks, full live wells and tooo much gear in the summer will kill the hole shot and make you think it's the motor. I have experienced this before. good luck
Mine was doing the same thing and had someone suggest for me to check the screen that is in the brass fitting above the fuel regulator, I removed the screen and found alot of trash caught behind the screen and in the fitting, so I cleaned it out and went to run it and that fixed my problem on the holeshot.
What fitting are you referring to that has this screen ?
All EFI motors have about a second delay before the motor will spool up. The computer has to read all the sensors and the open injectors for fuel to flow through the motor. But you have to make sure you keep the exhaust vent above the water when idling a 3 liter. If not it will cause the motor to load up and when you punch it the motor has to clear itself out before it will turn up. The vent is in the back center of motor by the tell tell better known as the pee hole. Trim the motor out some til that hole is above water whenever you are idling the motor and tuck it just before you go to plane out.
Another thing I have always done with my EFI motors is about every 4 tanks of gas I put a bottle of gumout fuel injection cleaner in the tank. Keeps the system in top working order. Get it at any parts store or wallyworld.
Richard
Mine has a brass fitting above the fuel regulator that is held in by 2 phillips screws, remove the screws and pull the fitting apart and there is a screen on the brass side. It is not hard to pull off but just aggrevating to get to because of the gas lines being in the way.
Stanford...can you post a picture of the fitting you are refering to?
"Give a man a fish and feed him for a day...teach a man to fish and, he'll lay out of work, miss dinner dates with the wife....and live happily ever after"
"He, who dies with the most toys, wins"
Here is a pic showing where to find the filter...
Thanks but looks nothing like my 300X .
Is this the 250xb set up ?
Thanks 492slayer, that is the one that was causing my trouble.
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by 492slayer »</td></tr><tr><td class="quote">Here is a pic showing where to find the filter...
Mark,
Nice Simon motor. Don't mean to hi-jack but what's the deal with "no bleeds" out of the cylinders ? I always wonders about Erics motors not having bleed lines that way. How's the MAD intake work for ya ? I'm reworking one right now that I'm going to try out on a 250 EFI motor. Anything special or tricks you'd care to share with me..............
Thx,
Gary
Growing old is inevitable, growing up is optional.......
S.W. Ohio
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by ccole »</td></tr><tr><td class="quote">ok , got my oil problem solved with check valve, thanks for all the replys. when i am ready to blast off and go to full throttle i have about a 1 -2 second delay , and after i have fished for a while sometimes it may have a 4 -5 sec. delay. i have changed the filter and it is still doing it. could this be from the ethonal . filter looked fine but it really feels like it starves for fuel on take off. after it is up and running it has no problems. thanks for any advise.</td></tr></table>
DEFINITELY check you fuel lines (better yet, REPLACE them with OEM - EPA approved lines and bulb).
MAKE SURE you're pumping your primer bulb firm BEFORE EACH AND EVERY engine start.
As for the question about "no bleeds"..... the bleed system on a "stock" motor is designed to remove, and re-distribute "puddled-unburnt" fuel at lower RPM's.
Perhaps Eric doesn't intend for this engine to be idling much.....
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Gary, this actually was someone else's motor with the oil injection removed. Eric sent this pic out to all his customers a few years back to check the filter. I had the MAD EFI when Eric originally built my motor in 2006, and I changed over to the Simon Intake when Eric developed it.. I have the original prototype intake for the stock 3.0L cowls. As far as the bleed lines, they are all there, they are just routed off the other side of the block. If you notice the red lines in the pic, they are bleed lines off the top of the block.
Is this something I should check on my xb? The screws and spacers on whatever that is in front of this filter will have to be removed to get at the screws on it. I don't wanna screw something up.
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