I’m at a loss - Evinrude 40

[flyingscott]

A 40 HP on a 15' boat should sing and move at about 32.5 MPH-----If it does not then some trouble shooting needs to be done.----Just had somebody drive 4 hrs for me to look at a motor.-----Trouble shooting found that one of the " new " parts he put on was defective.----Replaced it with a good used part and he is on his way happy as can be.

I will call BS on that kind of speed on that old of a 40 hp.

 

[Keegan7]

I will call BS on that kind of speed on that old of a 40 hp.

Well I have locked 30 mph on gps with just me in the vessel, so it’s not bs at all.

 

[KJM]

Have you ever tried the motor out of the water on a hose? Does it still act the same?

 

[Keegan7]

Have you ever tried the motor out of the water on a hose? Does it still act the same?

No because it’s not under load, but I haven’t necessarily revved the motor up really high on muffs before.

 

[racerone]

Testing for this issue is a waste of time on a hose.-----They bark and roar and sound great running on 1 cylinder.!

 

[Keegan7]

Testing for this issue is a waste of time on a hose.-----They bark and roar and sound great running on 1 cylinder.!

Yeah you’re not wrong, but this is not a matter of misfiring. I’ve ruled out that out already by pulling the wires while it’s under load.

 

[Keegan7]

Have you ever tried the motor out of the water on a hose? Does it still act the same?

I just tested it with the muffs and yeah it actually does the same exact thing it does in the water.

 

[tphoyt]

Maybe I missed it but have you run with a timing light yet or done a link and sync?

 

[jimmbo]

A 40 HP on a 15' boat should sing and move at about 32.5 MPH-----If it does not then some trouble shooting needs to be done.----Just had somebody drive 4 hrs for me to look at a motor.-----Trouble shooting found that one of the " new " parts he put on was defective.----Replaced it with a good used part and he is on his way happy as can be.

32.5mph? That sounds a little high, but with one of the prop rated engines(post 84/85), I would expect about 28-29mph

 

[Keegan7]

Maybe I missed it but have you run with a timing light yet or done a link and sync?

Yes I have ran a timing light and it’s perfectly in time. No I haven’t done a link and sync, but the cam roller is on the mark where it should be and the butterfly’s open as they should.

 

[tphoyt]

I have an 02 40hp on my homemade 18’ plywood skiff that will clock 35 on the gps on flat water.

 

[jimmbo]

Yes I have ran a timing light and it’s perfectly in time. No I haven’t done a link and sync, but the cam roller is on the mark where it should be and the butterfly’s open as they should.

When people are asking about the Timing Light, they are not necessarily asking about the Timing, but that have you used it to detect an Intermittent Miss of the Ignition.
As for the link and Sync... You need the correct Service Manual(preferable Factory) to get the proper settings and adjustment procedures.
Related to the Link and Sync, are both carbs fully closed at Idle?

 

[tphoyt]

The timing light would be for looking for a miss.
Nothing to do with the timing.
A proper through link and sync procedure may help you to be sure butterfly opens when it should as opposed to how it should. You have nothing to lose by doing it.

 

[Keegan7]

Yes

When people are asking about the Timing Light, they are not necessarily asking about the Timing, but that have you used it to detect an Intermittent Miss of the Ignition.
As for the link and Sync... You need the correct Service Manual(preferable Factory) to get the proper settings and adjustment procedures.
Related to the Link and Sync, are both carbs fully closed at Idle?

Yes and they are fully open at WOT, how do I check for an intermittent miss?

 

[jimmbo]

When you tested for Spark? Could it jump a 3/8" gap consistently?

 

[Keegan7]

Nothing to do with the timing.
A proper through link and sync procedure may help you to be sure butterfly opens when it should as opposed to how it should. You have nothing to lose by doing it.

Yeah I just don’t have the manual to do so, and it’s not very hard to observe that the butterflies are opening and closing as they should.

 

[jimmbo]

Yes

Yes and they are fully open at WOT, how do I check for an intermittent miss?

Try using a Timing Light, and observe the flashes

 

[Keegan7]

Try using a Timing Light, and observe the flashes

I’ve used a timing light. Am I looking for a missing flash? If that’s the case then there’s none. The light pattern was very consistent.

 

[jimmbo]

On both cylinders?

 

[jimmbo]

What do the Spark Plugs look like?