Newer motor problem

[wyo307]

Hello everyone I had a friend bring me his 1992 evinrude 8hp model E8RENM yesterday. He said that it was running fine and then just died out of nowhere and he hasn’t been able to start it since. I put it on the rack and put the spark test light on it and there is no spark on the top or bottom. This motor is running a charging coil that then goes into an ignition module then into another coil to the spark plug leads. How do I go about testing each individual piece to figure out which one is the problem? I am pretty comfortable with the old point systems but this new one is making me do some head scratching. One other thought that I had this morning was it could be the kill switch so can I simply unhook it to see if that is the problem or will it not run disconnected? Thanks for the help.

[fleetwin]

OK, well this CD ignition is really pretty simple, so don’t be afraid of it…I’m pretty sure what you have there is the UFI system, in other words, the powerpack is under the flywheel.
The first few tests are very simple, first you must do the "stop circuit elimination test". In other words, when the stop button is pushed (safety lanyard removed), the powerpack’s capacitor is grounded preventing it from storing a charge, killing the ignition….I guess I should have asked about the safety lanyard first, is it installed??
In any event, on this engine, the stop circuit is easily disabled. Look for the one pin black amphenol/rubber connector near the coils, unclamp and unplug the connector, then recheck for spark.
Next, you will want to ensure the powerpack (under flywheel) is properly grounded. Look for the black lead coming out from under the flywheel, it is usually grounded behind one of the coils. Check the ground connection with an ohm meter on the low scale, should be less than one ohm….
Hopefully, one of these two tests will uncover the problem…

[wyo307]

Thank you fleetwin. I am not scared of it it is just unfamiliar to me. Yes the lanyard is installed but I haven’t checked the switch yet. Yes it is a ufi system. I am comfortable checking the switch, charge coil, and ignition coil but the power pack itself is a little confusing to me. When you say to check the ground coming off of the power pack for less than one ohm where are you testing between? I am assuming the ground and where else? I found the service manual on boatinfo so I have been reading about it this morning so hopefully I will have it diagnosed this afternoon.

Also where the ignition coil is mounted to the block which is also where all of the grounds tie in there are nylon washers behind the coil. Does this coil need to be insulated from ground except for the ground wire that comes off of the coil?

I think that I either have a kill switch or ground problem but I am trying to figure out where it would be at this point.

Thanks again for the help.

[fleetwin]

Those goofy fiber washers can cause grounding problems if improperly installed, I really don’t know what the engineers intended them for, vibration/heat resistance perhaps? There are four wires coming out from under the flywheel, unless it is the sailboat model with the three yellow alternator leads as well.
In any event, the powerpack (referred to as ignition module in manuals) has four leads coming out from under the flywheel, two orange coil input leads, one solid black ground lead, and one black/yellow tracer stop lead. The solid black lead is usually grounded behind one of the coils. I would connect the ohm meter (low ohms scale) between the black lead (while still connected to block/coil) and a good/clean engine block ground, you should see less than one ohm resistance….
Checking the stop circuit for problems is easy, simply unplug the single pin rubber connector coming out from under the flywheel, usually clamped to one of the coils…
You can not check the charge coil without removing the flywheel, there are no charge coil output tests for this engine because the charge coil leads are not accessible with the flywheel installed. So, I’m hoping you find a ground problem, or a bad stop circuit, because replacing that powerpack/module is a royal pain on these UFI motors….

[wyo307]

Thanks again fleetwin! I currently have the flywheel off of it so that I could see everything. I found in the service manual for the motor that the charge coil should have 800-1000 ohms of resistance and the ignition coil should have 0.05-0.15 on the primarys and 225-325 on the secondarys. The stop circuit is easy enough to check as well. Since it was running then died I am hoping that it is just a ground which would make the most since. On the metal piece of the power pack where the magnet on the flywheel would come by it was all rusted up so I did clean that up but other than that everything appears to be in good shape.

Can I get away with eliminating those fiber washers? I don’t understand why the power pack wouldn’t be grounded straight to the block.

I did notice as I was looking over the motor that the carb cover (plastic) had cracked where the throttle lever pivots where it rides along the mag plate making it not want to throttle up it would just move out of the way. Can I just epoxy this back into place until a new one arrives or will that not hold?

I plan on working on this motor this afternoon so I will report back with my findings.

Thanks again for your help

[fleetwin]

OK, well I’m hoping you did the stop circuit elimination test before going through the trouble of pulling the flywheel. I don’t think there are any fiber washers mounted under the powerpack/module, did you mean to say the coils? Did you remove the charge coil to check the resistance, or just unplug the leads? If you removed the charge coil, you will need the locating ring to orient it properly onto the mag plate. In any event, I don’t think it will hurt anything to remove the fiber washers from the coils. I would reuse them if they are there, just check coil strap and powerpack/module grounds after resintalling the coils and ground leads.
You will probably end up replacing that carb plastic cover, the throttle linkage puts too much pressure on it, don’t think epoxy will hold. I am hoping the lastest pieces are more durable, get ready to choke on the price though.
So again, did you check the powerpack/module ground with an ohmmeter? Did you unplug the stop circuit connector and recheck for spark?

[wyo307]

Ok so I checked the stop circuit with an ohm meter and it is working as it is supposed to. I did unplug it and recheck spark just because but there is still no spark. I did not remove the charge coil because of the positioning problems that you mentioned. I simply unplugged the leads and checked across them and it seems fine. I reused the fiber washers behind the ignition coil just because they were there (I did mean to say coil sorry). I checked the primary and secondary circuits on the ignition coil for both the bottom and top cylinders. Both seem to be within the specs that I have found for the resistance. I cleaned all of the ground tabs and reinstalled everything then checked the ground as you had stated and it is good as well. This all leads me to believe that the power pack is shot but I would like to know for sure before telling my friend that. Is there any way that I can test the power pack with an ohm meter to determine that that is the problem? It isn’t my motor I am just looking at it for a friend so he will have to buy the parts for it but I would like to know exactly what the problem is before he goes out and starts spending money.

Thanks again for the help.

[fleetwin]

OK, well first please know that simply unplugging the stop circuit is the best test to eliminate it as a cause for ignition failure. Doing the ohm meter tests are fine, but know that it can check fine on the ohm meter but still be problematic. I read that you did unplug the stop circuit and check for spark, there was still no spark, so that rules it out as a problem.
You have checked the coils with an ohm meter, certainly seems unlikely that you have two bad coils. You have checked the charge coil resistance, there is no way to check charge coil output on UFI motors. There are no resistance checks for the powerpack/module, except to make sure it is properly grounded, which you have confirmed. You could check pack output with a PRV and load adapter, but am guessing you don’t have these items. I’m assuming you checked the flywheel magnets on the remote chance they are bad. You didn’t disturb the under flywheel air gap, so that is not likely to be an issue.
So, all that being said, I feel it is safe to conclude the powerpack/module is bad. The UFI system is a pain, because you have to disassemble that mag plate to snake all the new leads. Sorry buddy….

[wyo307]

Thanks again fleetwin! I guess I will tell him that he needs a new power pack and see what we come up with.

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