I've a got 1993 Force 40 that is giving me trouble. Sometimes it will work great and then it will just die and I can't start it. Then I can, then I can't again...
I was on the lake the other day and the engine just stalled. It wouldn't re-start and I had to row myself off the lake (21ft pontoon).
I apologize in advance for the long post but here are all the details:
The next day I started troubleshooting. The first thing I did was try to start it and it fired right up.
After 5 seconds or so I reduced the throttle to idle and it died. Then I couldn't get it to start again.
Compression test:
P1 = 140 psi
P2 = 150 psi
Spark test:
Nice bright blue/purple spark around 5/8" gap on both cylinders.
I realized I'd been mixing my fuel with a little too much oil. The Quicksilver oil container says 3 oz per gallon but it should be 2.6 oz per gallon.
I mixed new fuel and then began checking the fuel delivery system.
The primer bulb is in good shape. No leaks/cracks and stays firm.
The bowl is full of fuel. The pump seems to be working and the diaphragm is in good condition.
Then I found that the fuel primer valve was stuck. I pushed the manual button. After this I could hear the click of the solenoid valve when I pressed in the key.
So I turned the engine over but forgot to reconnect the spark plug wires.
Re-did the spark test and got nothing...
New ignition coils arrived 2 days later.
I connected them and the engine started right up.
This time I left the throttle open a little longer before reducing it to idle.
While fiddling with the throttle linkage I noticed it's a little sloppy. The cam was not in contact with the eccentric roller. If I manually moved the cam a little, it would move the timing linkage and the motor would get a little sputtery. I decided the timing linkage needed adjustment. I let the engine run at an idle while I thought about my next moves. Then it just died. I turned the key and it wouldn't start.
I don't recall what I checked next but in the process of inspecting the plugs and other things I managed to turn it over with the P1 spark plug wire disconnected (again).
Worried that I destroyed another coil I checked for spark. There was no spark from either coil even though coil 2 was connected to an installed plug when I turn the engine over.
Then I dug deeper into the ignition system:
It has a Thunderbolt CDI ignition with a single speed stator and adapter.
I ran the following tests in order:
Spark Test: FAIL
Stop Circuit Isolation: PASS (disconnect yel/blk, still no spark)
Switchbox Stop Circuit Test: PASS (290V at yel/blk wire)
Stator Output Test: PASS (290V)
Stator Resistance Test: UNKNOWN Measured 688 ohms. Presumed OK. Spec for original 2-speed stator says 6800 to 7200 ohms but this must be an aftermarket stator with the adapter.
Trigger Resistance Test: PASS (846 ohms)
Ign Coil Input Test: UNKNOWN (measured 0V but the manual does not specify this test. I tested with the wire still connected to the coil.)
Ign Coil Resistance Test:
P1 Primary: 0.2 ohm
P2 Primary: 0.2 ohm
P1 Secondary: 453 ohm
P2 Secondary: 452 ohm
So I think the stator and both coils are OK.
What I'd like to test next is the Trigger signal. The trigger resistance is OK but I haven't tested it's output. The manual doesn't specify a test procedure but I found that it should source 4V to the switchbox.
I have 2 new ignition coils and a new switchbox on the way.
I may have zapped the switchbox when I turn the engine over with the P1 plug wire disconnected.
Even still, before then, the engine has a history of starting right up, then dying. Then absolutely nothing. If I let it sit for a day it starts right back up.
I'm suspicious of the throttle/timing linkage as well as the trigger.
Does anyone have any suggestions?
Erik
I was on the lake the other day and the engine just stalled. It wouldn't re-start and I had to row myself off the lake (21ft pontoon).
I apologize in advance for the long post but here are all the details:
The next day I started troubleshooting. The first thing I did was try to start it and it fired right up.
After 5 seconds or so I reduced the throttle to idle and it died. Then I couldn't get it to start again.
Compression test:
P1 = 140 psi
P2 = 150 psi
Spark test:
Nice bright blue/purple spark around 5/8" gap on both cylinders.
I realized I'd been mixing my fuel with a little too much oil. The Quicksilver oil container says 3 oz per gallon but it should be 2.6 oz per gallon.
I mixed new fuel and then began checking the fuel delivery system.
The primer bulb is in good shape. No leaks/cracks and stays firm.
The bowl is full of fuel. The pump seems to be working and the diaphragm is in good condition.
Then I found that the fuel primer valve was stuck. I pushed the manual button. After this I could hear the click of the solenoid valve when I pressed in the key.
So I turned the engine over but forgot to reconnect the spark plug wires.
Re-did the spark test and got nothing...
New ignition coils arrived 2 days later.
I connected them and the engine started right up.
This time I left the throttle open a little longer before reducing it to idle.
While fiddling with the throttle linkage I noticed it's a little sloppy. The cam was not in contact with the eccentric roller. If I manually moved the cam a little, it would move the timing linkage and the motor would get a little sputtery. I decided the timing linkage needed adjustment. I let the engine run at an idle while I thought about my next moves. Then it just died. I turned the key and it wouldn't start.
I don't recall what I checked next but in the process of inspecting the plugs and other things I managed to turn it over with the P1 spark plug wire disconnected (again).
Worried that I destroyed another coil I checked for spark. There was no spark from either coil even though coil 2 was connected to an installed plug when I turn the engine over.
Then I dug deeper into the ignition system:
It has a Thunderbolt CDI ignition with a single speed stator and adapter.
I ran the following tests in order:
Spark Test: FAIL
Stop Circuit Isolation: PASS (disconnect yel/blk, still no spark)
Switchbox Stop Circuit Test: PASS (290V at yel/blk wire)
Stator Output Test: PASS (290V)
Stator Resistance Test: UNKNOWN Measured 688 ohms. Presumed OK. Spec for original 2-speed stator says 6800 to 7200 ohms but this must be an aftermarket stator with the adapter.
Trigger Resistance Test: PASS (846 ohms)
Ign Coil Input Test: UNKNOWN (measured 0V but the manual does not specify this test. I tested with the wire still connected to the coil.)
Ign Coil Resistance Test:
P1 Primary: 0.2 ohm
P2 Primary: 0.2 ohm
P1 Secondary: 453 ohm
P2 Secondary: 452 ohm
So I think the stator and both coils are OK.
What I'd like to test next is the Trigger signal. The trigger resistance is OK but I haven't tested it's output. The manual doesn't specify a test procedure but I found that it should source 4V to the switchbox.
I have 2 new ignition coils and a new switchbox on the way.
I may have zapped the switchbox when I turn the engine over with the P1 plug wire disconnected.
Even still, before then, the engine has a history of starting right up, then dying. Then absolutely nothing. If I let it sit for a day it starts right back up.
I'm suspicious of the throttle/timing linkage as well as the trigger.
Does anyone have any suggestions?
Erik
