1969 evinrude 85hp ignition question

[kmivens]

Hello, I have a 1969 85 hp evinrude that I picked up a couple of years ago and I have never been able to get it to run correctly. It will start and run well when cold, but after it has been running about 10-15 minutes, it will begin to sputter and miss and will eventually die completely and will not start. If I leave it about 1/2 hour it will start back up and run fine for a few minutes and eventually die again. I did replace the waterpump impeller as soon as I got the engine and it does not appear to be overheating.

This engine has had a conversion from the original amplifier type of ignition to an automotive car coil ignition and I am wondering if this could be part of the problem. I was recently given an amplifier and coil from an old 60 hp johnson that my uncle had and I am wondering if anyone else here thinks that converted ignition system may be part of the problem. I have not yet done a compression test and I will be doing that this weekend as well.

I don't know if the parts that I was given are any good as they have been sitting in storage for about the past 20 years. Does anyone know of a test that I can do on these parts prior to installing them that would determine if they are faulty or not.

Any input into this would be greatly appreciated. Thanks.

 

[Joe Reeves]

Re: 1969 evinrude 85hp ignition question

If the engine has been converted to automotive ignition... keep it that way!

If you pump the fuel primer bulb (acting as a manual fuel pump), does the engine continue to run?

 

[kmivens]

Re: 1969 evinrude 85hp ignition question

If the engine has been converted to automotive ignition... keep it that way!

If you pump the fuel primer bulb (acting as a manual fuel pump), does the engine continue to run?

I don't believe so. If I pump the bulb after it has quit, it will still not start. However, I have not tried to pump the bulb while it is still running to see if that corrects the problem. I will check that out this weekend when I am up at the cottage.

 

[Joe Reeves]

Re: 1969 evinrude 85hp ignition question

I don't believe so. If I pump the bulb after it has quit, it will still not start. However, I have not tried to pump the bulb while it is still running to see if that corrects the problem. I will check that out this weekend when I am up at the cottage.

Error here, corrected in post #6.

 

[kmivens]

Re: 1969 evinrude 85hp ignition question

If that doesn't help and the engine still quits running as you've explained... quickly remove the spark plugs and check for spark. If no spark, do the following test.

(Battery Capacitance Dischage Powerpack Test)
Various OMC Engines - 1968 to 1972)
(J. Reeves)

Purchase a small 12v bulb at your local automotive parts store (the 12v bulb is to look like a flashlight bulb, not a headlight bulb). Solder two wires to that bulb, one to the side of the bulb (ground), and the other to the positive point. You might use a bulb of a somewhat lower voltage to obtain a brighter glow... just a suggestion.

Remove the spark plugs. With the key in the on position, make sure that you have 12v going to the pack at the terminal block (purple wire). Now, connect the ground wire from the bulb to any powerhead ground. Connect the wire from the positive point of that bulb to the powerpack wire that is connected to the coil wire on the terminal board (blue wire).

Crank the engine and observe that bulb closely (CLOSELY!). If that bulb glows even the slightest bit, the powerpack is okay. It may be a very dim glow... just so it glows! If it doesn't glow, the pack (amplifier) has failed.

Thanks Joe. Does this mean that you are recommending that if I have a poor spark that I should install the amplifier and coil onto the engine and replace the auto conversion system? If the spark is good, is there anything else that you can think of that might cause this. Someone mentioned to me that bad engine seals may be a culprit, but I have not heard about that.

 

[Joe Reeves]

Re: 1969 evinrude 85hp ignition question

Thanks Joe. Does this mean that you are recommending that if I have a poor spark that I should install the amplifier and coil onto the engine and replace the auto conversion system?

Oh Geeeze!... I got sidetracked as I was simply referring up to the year and hp of the engine instead of keeping to the conversion. I'm going to chalk that up to a senior moment, sorry.

Please disregard anything I mentioned pertaining to the old solid state ignition, and instead do the following:

If the engine stops running even though you have been pumping the fuel primer bulb constantly, quickly remove the spark plugs and check for spark.

NOTE: You can use a medium size philips screwdriver (#2 I believe) inserted into the spark plug boot spring connector, then hold the screwdriver shank approximately 1/4" away from the block on that model to check the spark.

If no spark at the plug wires, test the spark from the coil by removing the coil wire from the distributor and holding the brass threaded end of it 1/4" away from the powerhead when cranking the engine.

If no spark directly from the coil, first check to see if you have the proper voltage applied to the (+) terminal of the coil. If you have voltage but no spark, suspect a faulty coil. If you do not have voltage, find out why.

If on the other hand, you DO have spark from the coil but not at the plug wires, suspect either improperly set points, a failing rotor, or a distributor cap with an intermittent short.

The normal setting of the points of this model if it was still using the solid state ignition would be as follows.

The points must be set to .010 but no wider than .010..... BUT in some instances due to a possible slight inaccurately machined crankshaft lobe or a slight offset of one set of points, a setting slightly less than .010 would be required as follows.

Whether the crankshaft has two or three lobes, when setting the points, check the setting of the points on each individual lobe by rotating the crankshaft by hand.

You may find that setting one set of points to .010 on one lobe, then turning the crankshaft to the next lobe, the gap measures .011 or .012 (too wide). This is where you would need to close that gap down to the required .010. A gap too wide can result in a ignition miss when throttle is applied.

Bottom line, pertaining to the point setting at the various lobe locations____ .010, .010, .009, is okay____ .010, .010, .011 is not!

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However, due to the conversion, should the above create a problem, try setting the points on the high lobes so that a .020 gauge will go thru but a .022 will not.

Perhaps other members who have made the conversion will jump in here with their comments pertaining to whether the gap setting of the points needed changing or not. I don't see why it would BUT..................

 

[kmivens]

Re: 1969 evinrude 85hp ignition question

Thanks Joe. I will check these things out this weekend. Much appreciated.

 

[kmivens]

Re: 1969 evinrude 85hp ignition question

I did a compression test on the weekend and the results were:

Cyl1 - 112 PSI
Cyl2 - 120 PSI
Cyl3 - 115 PSI
Cyl4 - 112 PSI

I started the motor and ran it for a few minutes and the usual problem started and it quit and would not start. However, I noticed that it was not turning over very quickly and that it might not be charging properly. I put another fully charged battery in and the boat started and ran without a problem. I determined that the rectifier had blown and I guess the battery discharged to the point that it could not provide enough juice to keep the ignition running. I put another rectifier in and it seems to be running much better; I ran it for about a 1/2 hour yesterday without the motor quitting.

However, I do have a bit of a high speed miss which I am attributing probably to the points or perhaps the rotor/cap. I tried adjusting the points but that did not seem to make a difference. Is there any way of testing the cap and rotor to see if they are defective?

 

[Joe Reeves]

Re: 1969 evinrude 85hp ignition question

The high speed miss is usually due to the critical point setting... give it a try as mentioned above when you have time.

I recall doing such a test a few times (cap & rotor) but it was using special equipment.