Evinrude 70 - No power in the water

[RoscoeP]

I really need some advice.

I have a '92 Evinrude 70 2 stroke. The VRO has been removed for several years and used to run great but now I have no power when I give it throttle. It sat for a couple years before I inherited it so I knew some work would be necessary. I was on the boat the last time it was used before storage and ran like a champ. I have been around boats for many years but I am certainly no expert but this has me stumped.

Here is what has been done:
* completely cleaned the tank
* brand new fuel lines (others were old)
* brand new fuel/water separator
* carbs (3) rebuilt by a qualified mechanic (not me) and were never hooked up to fuel until after cleaning of tank and new lines
* compression of 118, 119, 117
* great blue fire to all plugs
* several wires replaced because they just looked like they needed it

Symptoms:
A quick turn of the key and the motor fires right up in the driveway on the hose AND fires right up when in the water. After idling out of the ramp area and give it throttle the engine simply bogs down. It does gain a couple of rpm's but will not run right. I never payed attention to the tach but my guess is that 2k rpm max. Put it back on the trailer, pull it out and I can get more rpm's (never rev'ed it very high but higher than what I get on the water). Starts so easily and idles without missing a beat but won't plane a 15' boat. Two weeks ago I did get it to run properly one time for a few minutes and then after slowing down I could not get it to go again.

I have been trying to figure this out for several weeks and I am thinking of taking it and starting my own reef with it.

What am I missing?

Thanking all of you in advance.

 

[glenn property of pam]

Re: Evinrude 70 - No power in the water

does the fuel bulb get firm before starting and does the motor react if the bulb is squeezed.
Does the advance lever move with the throttle (check when not running)
Pull the air cover and do the carbs open fully when throttle is at wot (check when not running)
what do the plugs look like do they look the same or is one cleaner or wetter than the others.
If you have a timing light and a friend at 2k with throttle set a little higher is there a pulse of all 3 spark plug wires.
Any alarms? should bleep when you turn the key on.
Any missing hose between the carbs especially on the primer system or any air leaks before the fuel pump.

If the fuel system was rebuilt there is a chance that dirt can still get in the carbs so you can not rule the carbs out just because they were rebuilt. Basics you need fuel/air/compression/spark/timing on all 3 cylinders as 2 cylinders is not enough.

 

[Tripp Halbert]

Re: Evinrude 70 - No power in the water

pull one plug at a time while trolling. If one is removed and nothing changes, that cylinder is your problem. Worked for me the other day..

 

[willy007]

Re: Evinrude 70 - No power in the water

Does the primer bulb stay hard? Fuel pump may have worn out.

Side note: If it has been sitting for a few years it wouldn't hurt to change the impeller in the water pump

 

[RoscoeP]

Re: Evinrude 70 - No power in the water

Does the primer bulb stay hard? Fuel pump may have worn out.

Side note: If it has been sitting for a few years it wouldn't hurt to change the impeller in the water pump

Bulb stays firm- not as hard as when I stop squeezing, but stays quite firm.

Impeller was changed and pees like a race horse.

edit: I got a new fuel pump so I am going to rule out that the pump is wore out.

 

[RoscoeP]

Re: Evinrude 70 - No power in the water

pull one plug at a time while trolling. If one is removed and nothing changes, that cylinder is your problem. Worked for me the other day..

Did this in the driveway and there is a noticeable difference on each cylinder. I did not try it while on the water.

Should I even though I notice the difference while on the hose?

 

[xjdriver]

Re: Evinrude 70 - No power in the water

Make sure timing is advancing, all the way to stop at wot

 

[RoscoeP]

Re: Evinrude 70 - No power in the water

does the fuel bulb get firm before starting and does the motor react if the bulb is squeezed.
Does the advance lever move with the throttle (check when not running)
Pull the air cover and do the carbs open fully when throttle is at wot (check when not running)
what do the plugs look like do they look the same or is one cleaner or wetter than the others.
If you have a timing light and a friend at 2k with throttle set a little higher is there a pulse of all 3 spark plug wires.
Any alarms? should bleep when you turn the key on.
Any missing hose between the carbs especially on the primer system or any air leaks before the fuel pump.

If the fuel system was rebuilt there is a chance that dirt can still get in the carbs so you can not rule the carbs out just because they were rebuilt. Basics you need fuel/air/compression/spark/timing on all 3 cylinders as 2 cylinders is not enough.

All my typing disappeared so here it is again.

* The bulb gets hard when squeezing, loosens up just a bit but remains firm when running. It does not go limp or vacuumed shut.
* The advance lever does move with the throttle.
* The old plugs looked good. I matched them to pictures I found online of various conditions of plugs. Since the new plugs have some time on them I checked them and they look to be on the same path - appear to be operating properly.
* No timing light
* There is one short beep when I first turn the key to the run position. After it is running there are no other alarms going off.
* All fittings are hooked up and each hose is connected in a uniform manner.
* I have been very diligent in re-doing the fuel system and I am very confident that it is not a fuel issue.

The last item I would like to check with the fuel system is how do I check to ensure that all carbs are supplying the same amount of fuel?

I am thinking it has to be an electrical issue.

I know how to test a spark plug wire to see if it is good. How do I check the plug wire from the power pack? How do I check the power pack and what should the readings be?

What and how do I check to make sure there is enough juice getting to the power packs and what should these readings be?

Thanks again.

 

[RoscoeP]

Re: Evinrude 70 - No power in the water

Make sure timing is advancing, all the way to stop at wot

I will check this but right now I am out of town.

Thank you.

 

[Watermann]

Re: Evinrude 70 - No power in the water

Have you got the new fuel pump on yet? It sounds to me like the diaphragm is ruptured or maybe just turned into a piece of leather from age. While you have the pump off be sure to check the vacuum hole isn't plugged up.

 

[RoscoeP]

Re: Evinrude 70 - No power in the water

Yes, the pump is on. It seems that I get enough fuel into the carbs. But I would like to somehow test how much fuel is coming from each carb to make sure that the same amount of fuel is being supplied to each cylinder.

 

[Tripp Halbert]

Re: Evinrude 70 - No power in the water

if you have blue spark on all, then id say its safe to assume your coils and power pack are operating properly. To answer your question about still testing it on the water....its good you can notice a difference with each plug so this is probably not your problem then. the motor will show its true colors in the water though. hmmm, well i know you had carbs rebuilt, but this definitely sounds like a high speed jet problem.

 

[Chinewalker]

Re: Evinrude 70 - No power in the water

Have you pulled the plug wires to check to see if the motor is running WHILE you are trying to give it the gas under load? It's possible the mid- or high-speed range carb jets are plugged. Checking while on the hose won't tell you much...

 

[Tripp Halbert]

Re: Evinrude 70 - No power in the water

Yep i agree, pull plugs under load. Bring rubber gloves haha.

Also, have you put your hand over each carb to see if each one kills the engine? Not really the greatest way to test problems but atleast you can tell how much vacuum, if any, the carb is creating...

 

[RoscoeP]

Re: Evinrude 70 - No power in the water

I sure thank you for the suggestions and will try these suggestions and report back.

Keep the ideas coming.