Hey folks, this motor has a powerhead remanned 2 years ago installed by my mechanic (he had it on his personal boat when I needed it, he's a good friend) - compression was supposedly all good. The old motor would rev to about 5500 rpm and 52 mph. Now it wont rev but to 4500 RPM at 37mph, and has started missing / sputtering above 4000 rpm. Occasionally, it will choke throttling on plane. Same prop / lowers. Replaced plugs, vro / fuel pump assemble, new bulb, fuel water separator, cleaned carb jets, fuel filter clean, fuel in separator clean as can be. I have a remote tank filled with fresh fuel I am going to try to see if it's a blockage from the main tank, which might explain the missing, but what about revs? What else may be happening? power pack maybe?
thanks!
John
a cracked fuel line maybe?
When was the last time it ran ? I say you have a fuel related issue. Were the motor / carbs winterized ? If fuel has been sitting in the carbs for any time it would be good to get them rebuilt. Especially with the crap fuel you all have when it comes to storing it. Could be a plugged high speed jet.
I'd double check your compression again on all of the cylinders and then spark and finally evaluate the fuel supply. I had a 2005 Johnson 225 Ocean runner on my old Mako and it was the worse motor I ever owned. Had the power head rebuilt under warranty VRO failure, finally had to disconnect the VRO when it was out of warranty and it still was a lemon. Good Luck with it. OMC's nightmare years. Finally the FICHT investment put them under and they sold out to Polaris. After that, I went diesel inboard. I'll never go back to outboards as I don't need to go fast anymore. I was a Johnson /Evinrude fan all of my life until then.
Brings back memories (won't get into good or bad). I chased a misbehaving 95 Ocean Runner 200 for a couple years swapping out plugs/wires/coil packs, replacing fuel filter & rebuilding carbs & debunking cylinders trying to get another few hrs on it. Compression was down on 1 cylinder (~ 70psi) but it still ran. Then one day wouldn't fire so after all that I Figured the power pack went so I gave up.
I would second checking compression because if that's bad probably time to move on. If it's good you'll eventually find it. Good luck.
Thanks folks! will try all the above....
Jeff, I run the boat at least three weekends a month, and only ethanol-free 93 octane in all my boat; also add Staybil in winter anyway. I've run seafoam through it also.
carb with high rpm issues = high rpm jets clogged.
I was having similar issues with my little honda, my buddy asked me use Sea Foam.
All clear now, I am sold, I run Sea Foam in everything now :-)
thanks folks!
on it....
Was hoping to get another couple years out of it then repower with four stroke Zook. I have DF175's on my Mckee Express and love them. The Oceanrunner is on a Daugherty Yachts (first year) Edgewater 1800 Marlin I purchased in '04. It gets the majority of my boating use, and is still in really good shape otherwise- I have rewired / replaced electronics, T Top canvas, and cushions and keep everything covered when not in use, and it gets a bath after every use.
yup, clogged high flow jets. sometimes you can use the straw from a broom to clean them if plain carb cleaner spray does not work, but usually carb cleaner alone will do the trick!
Have carb cleaner and broomstraw! I like this one-cheap and easy! Thanks Boss! Will try that first up. Then a few unrelated electricals from bouncing around.
More fishing, less mechanicing!!!!
Quote from: thorhammer on March 24, 2020, 02:03:09 PM
Thanks folks! will try all the above....
Jeff, I run the boat at least three weekends a month, and only ethanol-free 93 octane in all my boat; also add Staybil in winter anyway. I've run seafoam through it also.
Dang! Your doing it perfect as far as your fuel. If it was no more than a 500 - 1000 RPM drop with out the sputter & choking out during acceleration we could say it was spark being you lose 500 or thereabouts for every cylinder that's not firing. I could be wrong, it does sound like a simple fuel problem... Jeff
I just got done helping chase down a fuel delivery issue on my buddies 125 Eforce 2-stroke. Your symptoms sound remarkably similar. He actually had fine debris that was hindering the needle/seat assembly on one carb so that he wasn't getting full fuel flow to the bowl and would quickly starve of fuel. - John
With cars change spark plugs again I don't know how many times advance sold me a bad plug,,,, ??? and 1gallon of racing fuel to every 10 gallons for fuel problems,,,,,,,,, ;D
Hey John, have you checked for fuel fracking? I had that problem after they started using ethanol in with gasoline. Dominick
Quote from: Dominick on March 27, 2020, 06:48:33 PM
Hey John, have you checked for fuel fracking? I had that problem after they started using ethanol in with gasoline. Dominick
Is that when ethanol dissolves the inside of the gas tank?
-steve
While running at speed, partially cover each carb with your hand or fingers one at a time. This should figure out which cylinder is acting up- it'll be the one where the engine doesn't drop in rpm or power.
If there is a clogged jet, this additional vacuum can pull the blockage through and immediately rpm and power will increase.
I'd start at running it off a portable tank like was your original plan. Keep it simple and verify each step.
Quote from: BradH on March 28, 2020, 12:19:05 PM
If there is a clogged jet, this additional vacuum can pull the blockage through and immediately rpm and power will increase.
This is good advice . Works very well a lot of times. Done this to get others motors running right on The River. Comes up at the beginning of the season, after people run their boat first time from winter storage or have let gas sit untreated in the tank for weeks or months... Jef
Quote from: Dominick on March 27, 2020, 06:48:33 PM
Hey John, have you checked for fuel fracking? I had that problem after they started using ethanol in with gasoline. Dominick
Hey Dominick, I only run ethanol-free high octane in all the boats, I had a really nasty problem in a previous boat before we could get the good stuff. Changed fuel water separator JIC but what came out was pristine.
UPDATE: ran the boat this week and the sputtering above 4000 has stopped- I'm going to guess I ran enough fuel / stabile / seafoam through that some varnish or debris got gone. Runs smooth enough now, just still wont go above 4500...to be continued...we have shelter in place starting today so may be a bit before I can get back after it.
Are there ports on the carbs you can spray carb cleaner through? I saw some engines with those ports where you can insert a plastic nozzle of a the carb cleaner and clean er out.
side note: my little 2 hp honda was stored with gas all winter and it gummed up, sea foam did not cut it. I called a buddy and he said try Chemtool, but I need to be careful with chemtool as it is not kind on rubber parts.
Can you take off the plugs for each cylinder and take a peek at them, the color might shed some light if it not getting enough gas and running lean etc.