83' Evinrude problems

[jsylvester08]

Hey Everyone,
So I got a 1983 Evinrude 115 over this past off season. When I got it I had the person run a compression test on all 4 cyclinders and it was 140 on each cylinder. Now when I run it, it feels like it has no power. It starts up and when I put it to full throttle it takes almost 3-5 min to get up on plane. It also does not sound like its running at full power. After it finally gets up on plane the motor will then rev up and push the boat fine through the water. It also will only get on plane with 1 or 2 people in the boat if there are 3 people it will never have the power to get up on a plane. I have a 0sprey 200 so I dot think its underpowered b.c last year I was running a 90 which always got up even with 6 people in the boat.
Does anyone have any ideas?
Do you think I should take it to a mechanic? I try to do all the work myself but im out of ideas

Also to get it to start I need to spray starting fluid into the carb. almost everytime could this be the problem?
Thanks
JP

[pete]

wrong prop ?

[Keith Knecht]

Could be starving for fuel.  Check the fuel filter, squeeze bulb,fuel pump.

[Circle Hooked]

If you have to spray starter fluid to start it you have a choke problem for sure,might be time for a carb rebuild or replacement, that might solve alot,

[fitz73222]

If you have a water separating fuel filter change it. What boat do you have and what propeller pitch do you have? Your compression is a little high believe it or not. You could have a carbon build up issue that raises the compression because the rings are stuck and not "breathing" properly. Your engine has "pressure back" keystone style rings that actually move in and out against the cylinder wall depending on stroke position. If they can't move, part of the fuel charge is lost do to blow by that interupts the fuel scavanging into the transfer ports that feed the cylinders. So she may be "coked" up. Get some Valve Tech engine cleaner and follow the instructions on the can. Basically it is spraying this solvent into the carburator venturies until the engine stalls and letting it sit for 20 minutes and then taking it out and blowing the carbon out. It is amazing what this will do to improve engine performance. You could also have a bad coil and she is only running on three cylinders and still maintain a reasonable idle or the coil drops at high speed. you have one per cylinder. Look for cracks on the exterior. This was a big problem on these V4's. Try running the engine on a flush at night and pull off each plug wire while its running with insulated or plastic pliers and see if the coil exterior lights up like a christmas tree trying to find ground. I believe your engine has Ferrite core coils; they should be black, earlier designs were green that were more troublesome. Also try running the engine on a remote six gallon tank to begin the process of isolating wheather or not you have a fueling or ignition problem. This will get us started down the path of which issue you have. One other thing; see if the bottom two cylinder spark plugs look dry compared to the top two or vise versa. This can indicate a bad upper or lower crankshaft seal; that usually shows up as a spit and backfire at idle that can cause a lean condition at high speed and cause power loss.

[RickK]

If you have a water separating fuel filter change it. What boat do you have and what propeller pitch do you have? Your compression is a little high believe it or not. You could have a carbon build up issue that raises the compression because the rings are stuck and not "breathing" properly. Your engine has "pressure back" keystone style rings that actually move in and out against the cylinder wall depending on stroke position. If they can't move, part of the fuel charge is lost do to blow by that interupts the fuel scavanging into the transfer ports that feed the cylinders. So she may be "coked" up. Get some Valve Tech engine cleaner and follow the instructions on the can. Basically it is spraying this solvent into the carburator venturies until the engine stalls and letting it sit for 20 minutes and then taking it out and blowing the carbon out. It is amazing what this will do to improve engine performance. You could also have a bad coil and she is only running on three cylinders and still maintain a reasonable idle or the coil drops at high speed. you have one per cylinder. Look for cracks on the exterior. This was a big problem on these V4's. Try running the engine on a flush at night and pull off each plug wire while its running with insulated or plastic pliers and see if the coil exterior lights up like a christmas tree trying to find ground. I believe your engine has Ferrite core coils; they should be black, earlier designs were green that were more troublesome. Also try running the engine on a remote six gallon tank to begin the process of isolating wheather or not you have a fueling or ignition problem. This will get us started down the path of which issue you have. One other thing; see if the bottom two cylinder spark plugs look dry compared to the top two or vise versa. This can indicate a bad upper or lower crankshaft seal; that usually shows up as a spit and backfire at idle that can cause a lean condition at high speed and cause power loss.

WOW
You are DA MAN (and he's one of OUR members)    

[Woodinator]

What fitz said X2.  I've got a ton more questions before I can throw a few more detailed suggestions your way, but I agree you need to eliminate the obvious first.  Do NOT use starting fluid.  Has no lubrication and can damage your engine.  Mix a spray bottle of premix fuel if you need to prime her more than what your solenoid can do on its own (...and have you verified that your solenoid does pump fuel to the carbs when you depress the key switch?  140 compression is definitely too high.  Should generally be between 110 and 120 for proper operation.  Do the valve tech treatment for sure.  Does the engine idle smoothly and evenly?  Is the problem only noticeable when trying to throttle up and get on plane?  If so, then most likely high speed jets in carbs. However, since it's hard to start it I'd guess it probably doesn't idle too well either.   Once you've run off a separate fuel tank to eleminate supply problems, then verify spark at each cylinder.  If spark is good, then high probability you just have a fuel delivery issue.  I, f not, then your culprit is probably a plug-wire, coil, or powerpack.  The only other obvious thing that comes to mind is timing. Make sure your linkage from the throttle arm to the stator under the flywheel is still attached and functioning properly.   In my experience, the hard starting problem is the key piece of evidence and means it's probably some sort of fuel delivery issue.  I've blown cylinders and screwed up timing linkages and these engines still started easily when fuel was still getting to the cylinders.  

Sorry if any of these items are elementary for you.  Just need more info and don't want to skip over too many "should be obvious" items and waste time or money chasing something more involved.

Fitz-thanks for the crank seal pointer.  Didn't know that one!

[akbridge]

It sounds to me like to big of a prop.  What RPM are you turning at wide open throttle?  Is your throttle linkage adjusted correctly and seeing wide open?

[Boatdood]

If you can stand another opinion I have one.

Compression tests are nothing more than a suggestion. A good result is not a guarantee any more than a bad result is, but the most important thing to note is that the numbers are extremely close on all cylinders indicating that the cylinders and rings are OK. Note the word "indicating". Problems have a way of hiding, but I'm betting compression and ring related problems are not the issue here.

To comment on the coking and carbon issues; they are certainly prevalent on these engines and my prior comment is not intended to discount that fact in any way, only to say that in this case I don't think it's the cause of the low power.

So what is the cause? Frankly we don't have enough information yet to do anything more than speculate, but it's fun to speculate sometimes. If it's not compression we move on to fire and fuel. It's simple enough to remove one spark plug wire at a time to see what happens. If it runs worse, it was firing on that one; no change and that one's not working, but remember this can be either fire or fuel related. At least if you find a cylinder that's not working you know where to start looking. If you're careful and lucky you can insert a screwdriver into the spark plug boot and check for fire by letting it jump a gap to ground. It should jump up to 1/2". If the cylinder is dead but getting fire the cause is looking like fuel.

Moving on to fuel the hard to crank may or may not be related to the loss of power. The cranking circuit consists of a series of tiny fuel lines and nipples where fuel is sprayed into the intake. This is actuated by a solenoid which opens a valve. A failure of any part here can cause hard cranking but once the engine gets started and warmed up that system is out of the picture and can't cause the loss of power unless it sticks in the on position. That's not happening here.

I doubt if this is a fuel delivery problem. Fuel delivery is a problem that develops as the engine tries to maintain power rather than being obvious from the outset as the case seems to be here. We could have a fuel starvation problem though resulting from clogged high speed jets in the carbs or some other issue. A quick way to check for fuel flow through the carbs is to remove the breather from the front of the carbs and run the boat into the sun. Sunlight shining down the throat of the carbs will allow you to see the fuel flow. It should be even between each throat, and the amount of fuel flowing through there at high speeds will scare you.

Jumping back to fire for a bit though it's possible that the timing is not advancing. If I remember correctly these engines have a spring loaded advance lever and a stiff bearing on the timer base can hold the timing back. That pretty much kills the power but it's one of the easiest fixes.

I may have missed something but this ought to give you some things to look at.

Good luck with it.