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Hey there all, I have a few questions for you all. I have a 88 225 that came on a boat i recently purchased. First one is, when i take off out of the hole the power is great, but after i am at cruising rpm say around 3300 for a minute the engine starts hesitating/flutering just a little. If i give it mroe throttle it acts as if it wants to, it just cant. From the searching i have done on this board it sounds as if one or both of the fuel pumps could be bad. any other ideas i should check while i am down there tomorow. I figure if i spray some quick start in the motor while it is hestitating it will tell me its fuel right? My other question is do i need a temp gauge? the factory yamaha gauge works and the arrow is above the green thing on the gauge, just didnt know if i should connect an aftermarket unit. there is a random grey wire in the harness from the motor to behind the gauge thats not hooked to anything so i thought i could use that, but i didnt see a place to put a sender in, or know where. Any help and input into my excapades would be greatly appreciated. thanks again!!
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slopoke,
I would check the primer bulb when the motor acts up - if it has collapsed, then there is a restriction from there on back to the fuel tank - could be kinked vent hose or stuck anti-siphon valve or plugged up screen at the fuel pick-up tube.
If the primer bulb has not collapsed, try squeezing it a couple of times to see if the motor will pick up rpm. If it does, then I would suspect bad fuel pump(s).
Some owners replace fuel pumps on average every five years just as routine maintenance - you might consider it.
Also, if your motor is carbed (I believe it is), you could be experiencing stuck float valves. You might try a shock treatment with a strong detergent like SeaFoam or RingFree. If that motor was allowed to set up for more than a month w/o being run, then the carbs could be clogged up with gum/varnish. May need to do a carb kit install.
If you are going to install only one gauge for your motor, I would recommend a water pressure gauge instead of a temp guage. The pressure gauge is the best indicator of water pump performance. And your motor already has a two thermo switches mounted in the heads to give you an overheat alarm. The pressure gauge is a little more work to install, but well worth it.
The sender for both the water temp and pressure gauges go in the top of the cylinder assemblies just in front of the heads where you will find a 14mm hex ss plug. The sender for the water pressure usually goes in the port side and the temp in the starboard.
I recommend you get a Yamaha service manual for your model outboard - can order online at www.yamahapubs.com - it will pay for itself.
Good luck [img]smile.gif[/img] ,
Ken K -
thanks for the great reply. the only manual i had seen were clymer manuals on ebay, but hopefully i can get one at the website you listed. thank you for the response, oh and yes it is carbed
ScottComment
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well i went out and when it was acting up i squeezed the primer bulb and it didnt change anything but i did notice that the primer bulb did not feel completly firm. it felt almost as it does when you are priming it to first start. so i am wondering if it is before that? The boat has a big fuel water seperator on it before the bulb with one of those big replacable filters that looks like a car oil filter with a clear bowl on the bottom. I wonder if this could be the culpret, maybe it needs to be changed. when i bought the boat a few months ago the gentleman said it was fairly new, but i have had this problem since i bought it...Comment
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slopoke,
I think at this point, I would get a little six gallon tank and hook the outboard to it - bypass your main tank and big fuel filter. This would tell you if you have a problem from the primer bulb on back.
Sometimes primer bulbs go bad - they can develop cracks/leaks and allow air into the fuel line.
Inspect the bulb and hose connections carefully - any question, replace it.
If your outboard runs ok with the small tank, then your problem could be the water separator/filter. Bypass it to see if that makes any difference.
Also, if your tank is not venting properly, as I previously mentioned, then your fuel pumps could be starving for fuel. Try loosening the gas cap just enough for the tank to vent there when the motor starts acting up to see if that makes any difference (don't do this on a full tank and rough seas, obviously). Check for that anti-siphon valve also.
Good luck [img]smile.gif[/img] ,
Ken KComment
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Slop, do you see any water or junk in the clear bowl on the Racor filter? It never hurts to install a new element if you don't know when it was changed last. The random grey wire is usually a trim sender wire. Does your trim gauge work? If you don't know when the fuel pumps were changed might be worth it to install new ones as well, they're relatively inexpensive insurance.
MikeComment
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Well i figured out what the stumbling problem was. when cruising at 3200 rpm one of the venturies right inside the carborator is not pumping gas. on teh starboard side of the boat the middle carborator. it is not not a solid stream like the others it just randomly spurts a little, but not much. So now i just gotta figure out if i can clean it with it in there with a fuel cleaner or if i have to take it off. i have a keys trip in two weeks so i better hurry!Comment
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Try pulling the main jet out (the larger brass bolt looking thing screwed into the side of the carb bowl...) and spraying some Berryman's Chemtool spray (Walmart) up into the carb bowl. Inspect the main jet orifices and make sure they're clear of any debris that might block fuel flow. You might want to do that with all of 'em just to be sure. Inspect the O-ring seal on the end of the main jet and make sure they're not torn or cracked, if they are replace them (dealer item, $5 each...).
MikeComment
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ok i will definatly do that. It was So apparent when i was able to get off work early enough to take the boat out and look. just looking into the carbs while it was running and seeing the one carb not having a stream of gas was a good feeling of at least knowing where the problem was. So i will try pulling out that main jet screw tommrow and spraying that in there and hope for the best, thanks!Comment
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Thought i would do a post to let everyone know that my problem was solved with new fuel pumps. I pulled the main jets out and they all were fine so i had my dad come over and drive the boat while i played with stuff, and while the fuel primer was not collapsed when i would pump it the motor would regain RPM and run normal. So from all your great advise she is back up and running. Thanks for all the help, scottComment
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Scott,
Thanks for the feedback - glad you got it fixed [img]smile.gif[/img] .
Ken KComment
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