Full throttle and 2,500 RPM it will not go higher than that

[rd fla]

I just purchase a 98 RENKEN 1880 with a 115 Johnson. First boat I have done some work on it before putting it on the water, no gage was working and steering cable was bad, plugs and gas filter was changed and I added 10 gallons of mix 50:1 to an existing 10 gallons.
it started fine with a minor fault. With out the gears it rev perfect up to 5,000. On the first outing after going 30MPH on about 3,000 RPM it was perfect until I slow down on a no wake zone.
Know on full throttle and 2,500 RPM it will not go higher than that. it will only go about 4 MPH you do feel like the engine is like in need of air or gas, I don?t have a water temp gauge, but I can see the water coming out with pressure and not hot. The volt 13-15, nb It rev up to 5200 rpm without load (gear not engaged) and it is fine. I don?t know if this is normal when i changed the gas filter the old filter was full, when I installed the new filter it was empty do I need to fill up with gas the new filter before installing it.
Thank you in advance.

 

[jonesg]

Re: Full throttle and 2,500 RPM it will not go higher than that

All the signs say not firing on all cyl's, troubleshooting will zero in on where and why.
A timing light will quickly show if the dead cyl is sparking or not.
Its not good to rev up like that, if theres a fuel clog you're turning a cyl at 5K with no lubrication.
Do the troubleshooting without any high revving, its not necessary at all.

I would also draw some fuel into a glass bottle and let it settle, look for water at the bottom.
If you find water, syphon the tank out, empty filter/s , drain carb bowls and refill with new gas.

 

[bob johnson]

Re: Full throttle and 2,500 RPM it will not go higher than that

when it wouldnt go past 2500 rpms...have you since that MOMENT turned the key off and RESTARTED the motor?? and then tried to run full throttle again???

the S.L.O.W. warning system will limit the rpms to 2500 ...the motor will run fine up to that point...sounds like a top...but once it tries to go over 2500 it bucks and stutters..

the motor will idle perfect

this will not change until BOTH the key is turned off and the motor cools to less than 207 degrees

I am guessing your alarm didnt go off, because it wasnt working..like all the other guages were not working when you got the boat.

if you have since turned the motor off and then restarted and went out and it still wont go over 2500 rpms you have another issue.

good luck


bob

 

[rd fla]

Re: Full throttle and 2,500 RPM it will not go higher than that

Thank you for the information. I did notice that when i pulled of the old filter I did have water when I pour it into a glass. I did not think to look into it more deeply.

 

[rd fla]

Re: Full throttle and 2,500 RPM it will not go higher than that

Bob thank you for your reply, once I did expiriance the problem initialy I did stop and retry to no abail.
I just pull off the gas line hose after the filter and after the bulb. I did notice that gas was not present when I pump. I don?t know if that is normal. I did not have traces of water but I did prime the bulb to the point I had a good flow of gas. put the line back into the line leading to the engine and I started the engine and it is running fine. I will not know if this was the fix until I put it back on the water. I don?t have a light to test the cylinder i will need to ask friends. I will keep you posted.

 

[jonesg]

Re: Full throttle and 2,500 RPM it will not go higher than that

You can buy cheap timing lights at most auto part stores or even walmart, I think mine cost $27.
They come in very useful around outboards.

 

[emdsapmgr]

Re: Full throttle and 2,500 RPM it will not go higher than that

If you think you have fuel delivery issues, try constantly priming the fuel hose bulb. That will force extra fuel into the carbs. If the engine runs normally under load while you constantly prime the hose bulb, you may have a weak fuel pump. What year is the engine-hard to tell from your first post..