1994 Force 120 HP ignition problems

I purchased a Bayliner Capris with a 1994 Force 120 HP (SN 0E093566), and did some lower end and cooling system work with help from this forum.

I removed the prop and placed the engine in a 100 gal trough. Started up fine after priming the engine and turning the key a few times. 1200-1400 RPMs in idle, and I had it up to 3200-3400 RPM in forward. Water pressure was about 3 PSI in idle. Turned engine off after about 20 mins.


Waited about an hour, then tried to start it up again, but it wouldn't run. Spark plugs and #1 and #2 were black, while #3 and #4 looked clean. I cleaned the plugs and below are the before and after pictures.


Compression test shows 145, 150, 155, 150 psi.

I have the 1992 shop manual so I can work through the voltage and resistance measurements.
I tried the spark plug test with a tester, and didn't see any sparks. But I was cranking the engine with my remote switch connected to the starter, and not with the ignition key.

This is what the voltage regulator looks like. The black, burned looking areas were there when it was purchased.
Does this look OK? Can I test it?



How do I use the remote switch to test the sparks, stator and power pack voltages, so that I do not have to turn the ignition key?

TIA,
Chandran

That black spot might be a problem, maybe not.
Usually the stator is bad in a no spark on 2 situation.

But test it.
outboardignitiondotcom has test procedures.
Since you have the factory manual use the values in that book.
Sometimes the parts have already been changed and you might have an aftermarket part.
CDI makes most aftermarket electronics for outboards.
Their test specs are different on their equipment.

I think you can use a regular analog meter to do the basic tests but need a DVA meter to do the rest.

Hook the remote switch to a hot lead(one side of the solenoid) then hook the other lead to the yellow/black lead on the solenoid.

Always have a fire extinguisher handy.

E-bay is the cheapest place to find replacement parts.
They have a great return policy and back the customer 100%

I don't see a yellow/black wire on the solenoid.
For the compression tests I hooked the remote leads to the hot terminal (red) and the thin yellow/red wire.

From my picture, how to I hook up the remote starter so that I get sparks?

My bad!! Yellow/red.
Just turn the key on and it will be in spark mode.
Make sure the kill switch is hooked up.

My 1994 Force 120 HP has the red stator with 4 wires: 2 yellow AC wires, Grn/Wht and Wht/Grn wires.
The red stator is part#398-832075-A3
There is also a stator adapter that has the blue and blue/wht wires connected to the switch box, and a black wire.


Disconnected Blk/Yellow from Blk terminal on Switch Box (120 HP):
Sparks on #1,#2,#3,#4 with gap set to 1/4".
No sparks when gap set to 7/16", the specs in the service manual.

Reconnected Blk/Yellow to Blk terminal and no sparks.
I can't seem to locate a neutral interlock switch on my engine, so I don't know if that can be the source.
It ran for about 20 mins a few weeks ago. I killed the engine, then wouldn't start...the engine didn't die when running.
I was putting the engine in gear, so maybe something shorted in the shifter, or lanyard circuit.

Disconnected Blk/Yellow from Blk terminal and did the following tests.

Rectifier/Regulator:
Resistance tests showed bad results [X]:
Red to Yellow1 = 14.8 kohms [X]
Yellow1 to Red = 48.7 kohms [X]
Red to Yellow2 = 0.0 ohms
Yellow2 to Red = Open
Black to Yellow1 = 0.0 ohms
Yellow1 to Black = Open
Black to Yellow2 = 0.0 ohms
Yellow2 to Black = Open
--------------------------------------
Stator:
Meter fluctuates. Probes connected to each other gives 0.0-0.5 ohms
Yellow = 0.2-0.7 ohms
Wht/Grn to Grn/Wht = 683 ohms
DVA Yellow AC wires = 18 V
--------------------------------------
Switch Box:
Purple Trigger to White Trigger = 0.84 kohms
Brown Trigger to Wht/Blk trigger = 0.86 kohms
Purple Trigger to Engine GND = Open
White Trigger to Engine GND = Open
Brown Trigger to Engine GND = Open
Wht/Blk Trigger to Engine GND = Open

Purple to White = 6V
Brown to Blk/Wht = 5V
Purple to GND = 2V (next 4 readings fluctuates when cranked, sometimes spikes to 10V)
White to GND = 2V
Brown to GND = 2V
Wht/Blk to GND = 2V
Blue to Engine GND = 259 V (from stator adapter)
Wht/Blk to GND = 274 V (from stator adapter)
Black to GND 264 = V ("stop" circuit)

Green to GND = 1000+ V
Grn/Wht to GND = 1000+ V
Grn/Red to GND = 1000+ V
Grn/Blk to GND = 1000+ V
---------------------------------------
Ignition Coils:
Coil#1 = 1000+
Coil#2 = 1000+
Coil#3 = 1000+
Coil#4 = 1000+


Summary:
I will replace the rectifier/regulator because it tested bad.

The stator seems fine by the tests.

I am now going through blk/yellow circuit.
Lanyard switch bad?
Is there a neutral interlock switch for this engine? Can't seem to see one!

The trigger voltages from the switch box terminals shows spikes 1000+ V, and the coil terminals also read 1000+ V when the engine is cranked. The Force Service Manual gives specs of 150-250 V for the coil terminals.
Is the switch box bad? The manual is for 1992 models, and refers to a different stator with blue, blue/wht, red, red/wht leads, so I am not sure what to expect.

Just to re-emphasize, when Blk/Yellow is disconnected from Black switch box terminal, I get sparks from all four coils at 1/4" spacing, but not 7/16".

Any thoughts?

Maybe ignition is OK (except for stop circuit)?

Is it OK to test run the engine without rectifier/regulator for 10-30 mins?

TIA!

Neutral safety is in the shifter.
IF??? it's turning over with the key???
Then the switch is good.
It's only purpose is to stop you from starting while in gear.

Shouldn't hurt to run, just make sure it's not overcharging too much.

If the regulator isn't the culprit?
Try over on iboatsdotcom.

What are you using for a spark tester?

Thanks for the advice. I am using a spark plug tester from Autozone, the type where you clip one end to ground and the other to the plug harness and look for a spark to bridge an adjustable gap.

I got the Blk/Yel stop wire figured out...the lanyard switch was stuck on open. I removed the plastic shifter cover, which probably moved a little when I was fooling around with the shifter when it was running.

Do you think that the 1000+ V from the switch box (green wires) going to the coils is OK? Again, the manual calls for 150-250V for my stock coils.

Just waiting now for regulator to arrive later this week.

Not sure about the 1000v
Contact outboardignitiondot com
Or CDI ignition and ask them.

Replaced the stock voltage regulator with aftermarket Celox 5-wire.


Since motor wouldn't start, I took apart the carbs for inspection and everything looked clean. Sprayed carb cleaner into main and intermediate jets and needle. New gaskets. New 5/16" fuel line secured using ss hose clamps.

There is some 1/8" or smaller fuel line between the 2 carbs and the choke. I didn't replace, but there were two places where the ends were torn so I cut them back and re-secured onto the fittings using zip ties. Carb mixture needle was closed (clockwise), then backed out 1 full turn per service manual. Settings were 1 1/2 turns ccw before I took the needle out.


Placed the engine in fast idle, pressed choke on ignition switch, and cranked for about 5 secs. The engine started and died about 1 minute later. Squeezed primer bulb, choke and cranked for about 5 secs. Same thing, engine started then died fairly shortly. I turned carb mixture needle 1/4 turn ccw (richer), then cranked the engine without choke.

Engine started, I increased the throttle to keep from dying. Motor ran about 10 mins. Water pump working, When I increased throttle, the battery gauge approached 16V, then reduced to 14+ V when idle. Engine started making popping sounds. Turned ignition key to "off" but engine was still running. Pulled Lanyard switch to kill engine.

Pulled out spark plugs and all four were black. So now I know that all pistons are firing.
Black means too rich?


Cleaned off plugs after 1 hour cool down. Started motor with choke, and it started up. Increased throttle. Motor made a lot of popping noises in idle, less so in fast idle or in gear with throttle 1/2-3/4 full. Popping noises sounds like the engine is backfiring.

So what are the suggested steps from here to tune the engine?

The carbs are synchronized, but I haven't re-adjusted the idle speed or the throttle roller (seems to be centered between marks) or timing.

Thanks!

The popping at idle is probably the air screws.
They should be adjusted in the water in gear.
The air screws control the air/fuel mix at idle.
Past idle the main jet controls the air/fuel mix.
There is an idle jet but it's preset and can't be accessed.

The synchronizing doesn't need to be done until it idles.

Update: Blk/Yel wire was disconnected under the key switch, and that is the reason that the engine did not shot down when I turned the key to the off position.

Ignition problems are solved, and I will move to tuning the engine. Thanks for the help.

http://forums.iboats.com/forum/engi...ler-outboards/616464-carb-and-timing-tutorial

Here's a link to help doing the timing and setup.

One thing about a Force or any older outboard.
The timing doesn't jump or fluctuate unless YOU do something to it.

Most you need to do is check the static timing and change the plugs.

Make sure the gas is fresh and install a see through filter between the carb and the fuel pump.

Update.

The popping noise was due to a leak in the transfer port cover underneath the fuel pump. After removing the fuel pump, the screwed were found to be loose on the transfer port. I removed the port cover and half of the gasket was missing. I knew there was a problem in this area when I was diagnosing the engine in the evening, I could see the ignition in cylinder #3 from the gap between the cylinder block and transfer port cover! Ordered a new gasket, and all is fine.

The leak in the transfer port cover did not affect the cylinder compression, but did allow air in, which leaned out the fuel mixture and hence the popping.

Well done Chandran,Happy motoring