150 evinrude, update!

[Chinatown317]

I am still reaching my rev limiter at about 45 mph, 26 pitch prop annnnd i still have a lot of throttle left.
Any ideas on how to get more speed, 55ish mph?

 

[faztbullet]

Boat type and rpm?

 

[Oldsaltydog]

What are your actual RPM's? With RPM's and speed, we can determine if you're getting prop slip, which it appears you might be.

 

[Chinatown317]

Boat type and rpm?

88 Bumble Bee V178
1991 Evinrude Intruder
14.5 X 26 3-blade ss prop

 

[Chinatown317]

What are your actual RPM's? With RPM's and speed, we can determine if you're getting prop slip, which it appears you might be.

With this 26 pitch prop, i gained about 4-5 mph.
New prop, 5300-5500 rpm, 45-47 mph
If i go much higher in rpms, i am assuming i hit the rev limiter

 

[Chinatown317]

88 Bumble Bee V178
1991 Evinrude Intruder
14.5 X 26 3-blade ss prop

150 Evinrude

 

[faztbullet]

Not even close to limiter... post a pic of engine mounted on transom

 

[Chinatown317]

Not even close to limiter... post a pic of engine mounted on transom

Let me know if you see something out of place

 

[faztbullet]

Looks good....are you using the trim?

 

[Chinatown317]

Looks good....are you using the trim?

Motor trim, yes. Right around 5500-5700 rpms, the motor just loses power.... get off the gas and it goes just fine.... runs good @5200 all day long, but that is 40-42 mph.

 

[faztbullet]

When you say it losses power ..does rpm stay the same and speed drops or does rpm and speed drop together?

 

[Chinatown317]

When you say it losses power ..does rpm stay the same and speed drops or does rpm and speed drop together?

RPM's drop quickly and speed starts to drop obviously. But the RPM drop is quick/drastic!

 

[Chinatown317]

RPM's drop quickly and speed starts to drop obviously. But the RPM drop is quick/drastic!

When you say it losses power ..does rpm stay the same and speed drops or does rpm and speed drop together?

Any new ideas or thoughts?

 

[racerone]

Lower the motor.-----Verify RPM reading on your tachometer.

 

[Chinatown317]

Lower the motor.-----Verify RPM reading on your tachometer.

It's not blowout from the prop being out the water.... the motor has been dropped to the lowest setting and moved up until i got blowout at highest trim. Then dropped back down

 

[faztbullet]

Sounds like its dropping a cylinder/s. Could be ignition or fuel supply to carb/s

 

[Chinatown317]

Sounds like its dropping a cylinder/s. Could be ignition or fuel supply to carb/s

Dropping cylinders sounds like what it is doing! But why? And what is the fix?

 

[Chinatown317]

Sounds like its dropping a cylinder/s. Could be ignition or fuel supply to carb/s

Most everything has been rebuilt or replaced on the motor minus the stator. I am wondering what the motor acts like if the stator starts to go bad?

 

[racerone]

If you are convinced it is the stator , then spend more beer tokens on parts.----Testing , trouble shooting is a forgotten art I think.

 

[Chinatown317]

If you are convinced it is the stator , then spend more beer tokens on parts.----Testing , trouble shooting is a forgotten art I think.

I dont know! I am learning all this as i go, hence the reason i am here asking the knowledgable! It is losing power on top end..... all the fuel system has been touched? Not sure if it is loss of spark or what.

So, any help is appreciated!

 

[racerone]

Run with a timing light.---One cylinder at a time.------See how spark behaves when motor falters.

 

[faztbullet]

Also have someone manually pump the bulb when it acts up as could be VRO pump weak. Highly doubt its stator

 

[Chinatown317]

Thanks you guys.... i will update as soon as i can get some data!

 

[kevinj]

If you think it's ignition related then follow the OIS2000 troubleshooting guide. AS Faztbullet said, also have someone pump the primer bulb when it starts happening. If the fuel pump as a weak diaphragm or if you have a restriction in the fuel system this should overcome the delivery problem and you'll get full power.

https://www.go2marine.com/Product-Guides/MFR/CDI/johnson-evinrude-1991-2006.pdf

 

[Chinatown317]

If you think it's ignition related then follow the OIS2000 troubleshooting guide. AS Faztbullet said, also have someone pump the primer bulb when it starts happening. If the fuel pump as a weak diaphragm or if you have a restriction in the fuel system this should overcome the delivery problem and you'll get full power.

https://www.go2marine.com/Product-Guides/MFR/CDI/johnson-evinrude-1991-2006.pdf

Helper and timing light acquired! Taking boat to water in a min! Will update w new findings!

 

[Chinatown317]

New data from the run today!
Idled motor, spark on all 6 cylinders
Ran boat in water w/ my son squeezing the primer bulb at "stubborn" point, no change. Still lost power.
Hooked timing light up to each of the 6 cylinders and all acted/showed the same.
Boat got to 5300 rpm, 40ish mph, and wouldnt go anymore, still w about 1/4 throttle left.
TIming light was consistent on all cylinders......

Note to self, raise the trolling motor before testing!

Maybe this helps........