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I have a 25hp envirude...It idles perfect...But, when I try to accelerate it just gets up to about 4 mph and that is with the throttle half way down.....We have changed the spark plugs, cleaned out the carb and ran sea foam through the gas.....I checked the fuel line and it is fine...Anyone have any ideas?
Jeremy
Even though you cleaned carb it sounds like plugged high speed jet.
X2 or the ball is collapsing on the fuel line.Quote:
Originally Posted by cray
When you cleaned the carb, did you remove the float bowl drain in the front on the float bowl on the bottom? if not take the carb back off, remove the float bowl on the the bottom, then remove the plug in front. The high speed jet is in that pasage but it take a special shaped driver to remove it, a pocket screw driver will do more damage than good, I would got to a hardware store and buy a torch tip cleaning tool, it will have quite a few small rat tail files in it , work them into the jet so you can see it in the bottom of the tube in the middle where the imullsion tubes go into. get it cleaned and use carb cleaner with a straw in the nozzel and spray in there then try it again.
Have you checked your fuel pump??
Hi,Quote:
Originally Posted by SeaRay
It is a brand new fuel line on gas tank.....
Jeremy
What ArcherGuy1 said.
Also the fuel pick in the tank clean?
Next would be a hole in the diaphram in the fue pump.
is it an attwood(bulb) ? got one from walmart a while back that was leaking air arround the clamps . put zip ties and pull down very tight . cured my problem . thought it was carb but a mechanic at mississippi marine in tupelo said they had seen several like this . want take but two ties to find out .
Hi,Quote:
Originally Posted by eagle 1
I bet your right..Because, I purchased mine from walmart....I plan to just replace it with a better quality one....
Jeremy
I had a similar problem with a 25 Yamaha, 2007, 2 cycle. It turned out to be a missing jet from one of the carbs. Never did find the jet down in the motor anywhere, but new jet solved the problem.
What year OMC 25hp are you talking about? I always start by checking spark with an actual air gap spark tester. It should jump at least a 1/4" air gap with a hot blue spark. Those motors will idle pretty darned good with just one cylinder functioning, but fall on their face when giving throttle under load. They'll even rev up nicely on one cylinder when in neutral.
Once again, I'd check spark. IF spark is good on both cylinders, I'd pump the fuel bulb when giving it throttle and see if it makes a difference. If pumping the primer bulb helps, it may be the fuel pump.
If it's a newer OMC and you have bad spark on one cylinder, switch the coils and see if the problem follows the coil. If not, take your powerpack to a mechanic and have him check it with a DVA meter. They're too expensive to guess on.
JMO,
JBJ
Quote:
Originally Posted by bayoumonster
Hi,
Its a 1995 engine......The fuel pump was just recently replaced....I am going to replace the fuel line from the tank to the engine....We will check the spark...I also am going to replace the walmart brand fuel line that runs from gas tank to engine.....I am hoping this is the issue....
Jeremy
I'd go back over the linkage (assuming you took carb off to clean it) and make sure it's all connected and adjusted.Quote:
Originally Posted by jcd
I am still baffled with my engine....We once again took the carb off and cleaned it really well....I also repleced the fuel line/bulb.....The engine is still acting up.....It idles just fine.....But, once you hit the the throttle shift to pick up speed....It just gets up to around 4mphs and sputters/dies....This is with the throttle half way down..
Does anyone have any ides what it could be?.....I have a buddy who thinks it could be a bad head gasket....Also, one other buddy thinks it could be a bad stator coil....
I will change the head gasket...Hopefully, that is fix....I know the stator coils can be pricey.....I really don't want to have to go back to the boat mechanic...Because, I really don't trust them....Speciallly, when they can't actually truly test if your engine is running correctly...
Also the fuel pump is working just fine..We also checked the spark on the plugs.....
Jeremy
Thanks
Bye
got spark, got fuel---sounds like the timing is not advancing when you accelerate if you've checked that then forget this message it's just a thought.
That's what I was suggesting, but he made no mention of checking the linkage. (Could be as simple as the cam roller not being adjusted correctly)Quote:
Originally Posted by wannabe fisherman
Need to remove the cover and with motor off advance the throttle and be sure the throttle is opening and the timing advance is rotating around under the flywheel to it's stop.
Of course it's hard to internet diagnose unless one hears the motor. The sputtering/dying could also be from too much fuel being dumped when throttle is opened.
In the long run it could actually save money by taking it to a qualified mechanic and letting him see it. Throwing parts (money) into it at random is never a good idea $$wise.
How did you check spark? If you just grounded the plug on the block--not correct. Each wire should produce a spark that is capable of constantly producing a hot blue spark that will jump at LEAST a 1/4" air gap. If not, it won't fire under compression with lots of non-conductive hydrocarbons in the cylinder.
If there's not any milky stuff or water droplets on your plugs, and your compression is good, I wouldn't suspect a bad head gasket.
Also, put your throttle closed and see if the throttle plate in the carb is nearly totally closed, with only a TINY gap in between the plate and the wall of the carb throat. Next, put the throttle totally open and make sure the throttle plate is totaly open. If not, you have a synchronization problem. Also, when opening the throttle, the armature plate under the flywheel should rotate, but after about 3/4 throttle it probably has already reached full spark advance and won't rotate further with more throttle. If the armature plate is not moving at all, that could be the problem(doubtful).
I personally suspect weak or no spark on one cylinder.
JBJ
Hi,
I am going to change the head gasket...If it isn't that?...I will take it to boat mechanic...I just had boat mechanic work on it last year....Paid 400 dollars and he didn't fix it....Which he never did put the engine under a load...So, you can't be 100 percent sure it runs...Unless you can actually take it out and run or have a small pool to check it in..
Jeremy
more than likelyQuote:
Originally Posted by cray
Going to change head gasket...If that isn't fix...I am going to give up and just take to boat mechanic..
Jeremy
Any professional marine mechanic will have a test tank. He will attach a test prop to the motor and put it under load. If you're going take it to a mechanic, take it to a professional---it's usually worth the little extra they'll cost.
BTW, I'd save the time and money on a head gasket and just take it to a mechanic.
JMO,
JBJ