Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

[shane hawkins]

Just bought boat, replaced plugs with ngk's cap rotor etc... Problem is really hard to start, not sure if im setting choke properly or what, i have herd that cracking the throttle once should set it. Took it to the lake today got there and it wouldnt start, after getting it back home i found that shes getting no spark, coil wires have 10v with ignition on but as soon as i turn it over it grounds and the second you let off the ignition it goes back to 10v and trys to run? Ign switch? Also checked timing yesterday when i tryed to jump the spark advance with a wire nothing happened? So i just made sure it was @ 12deg btdc. Once it seems to catch when letting off ignition it runs great! I have downloaded the manual for this boat and it says to check resistance from coil to ground bracket and it should be infinate but i get nothing, it does read 0.4 ohms when jumping terminals as its suppose to. The exact same thing goes for the pick up. There is no kill switch.

 

[Rocky_Road]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

If you have the proper manual, look to see if you should be plugging the two wires going to the shift cutout switch together. Unless you do this, you are not in the timing mode for an EST. You will notice a definite change in the RPM's when you plug these two wires together (going to the switch, not the two leads coming from the switch).

Happy boating!

 

[shane hawkins]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

Thanks i will plug those wires together next time! No theory on the ignition issue?

 

[Rocky_Road]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

Thanks i will plug those wires together next time! No theory on the ignition issue?

If you set the timing without the shift cutout wires together, then your timing is quite a bit 'off'. Nothing will make any sense until you get the timing corrected. THEN...if you are still having the hard start condition, we can move down the probable cause list.

I had similar issues until I realized that I had did my timing without the engine being in the proper timing mode. The engine would run...but not like it should! What clued me in was the fact that the RPM's weren't changing when i used the jumper at the distributor only.

If you need a picture of the wires that I am referring to, just 'holler'!

Happy boating!

 

[boat127]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

how is the condition of the battery. put your red lead of you multimeter to the +side of your coil and the black lead to the -of coil with ignion on should be 12 volts.

 

[shane hawkins]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

If you set the timing without the shift cutout wires together, then your timing is quite a bit 'off'. Nothing will make any sense until you get the timing corrected. THEN...if you are still having the hard start condition, we can move down the probable cause list.

I had similar issues until I realized that I had did my timing without the engine being in the proper timing mode. The engine would run...but not like it should! What clued me in was the fact that the RPM's weren't changing when i used the jumper at the distributor only.

If you need a picture of the wires that I am referring to, just 'holler'!

Happy boating!

Having problems getting it to run so i can check timing, any ideas on getting it to run so i can check timing. Also when you unpluged the wires from the interupt swith what did you use to join them together? My problem right now is the signal wires going into the coil have 10v in the run position but the second you turn switch to start it loses it. The only way i can get it to run is when i let off from starting it and the 10volts come back and it catches. I also have been taking off the throttle cable and manually giving it gas so that slpit second ignition will catch! On your choke do you open throttle all the way to set? The choke dial on mine is set one notch lean. Yours?

 

[shane hawkins]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

how is the condition of the battery. put your red lead of you multimeter to the +side of your coil and the black lead to the -of coil with ignion on should be 12 volts.

It does while the key is in the run position, but when you turn key to start it looses it?

 

[Rocky_Road]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

Having problems getting it to run so i can check timing, any ideas on getting it to run so i can check timing. Also when you unpluged the wires from the interupt swith what did you use to join them together? My problem right now is the signal wires going into the coil have 10v in the run position but the second you turn switch to start it loses it. The only way i can get it to run is when i let off from starting it and the 10volts come back and it catches. I also have been taking off the throttle cable and manually giving it gas so that slpit second ignition will catch! On your choke do you open throttle all the way to set? The choke dial on mine is set one notch lean. Yours?

The two wires going to the interrupt switch have a female plug on one, and the second wire has a male plug...so they simply mate together.

As for setting the choke, all I can say is that I push the throttle full forward once to set mine...I can not speak for your setup. The base setting for the choke dial will have to found in the service manual, or maybe DonS will be reading this thread.

I wish that I could be more helpful!

 

[jminator2002]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

Hey Rocky Road, I'm having a similar problem getting my 1996 3.0LX engine into base timing mode. When I take the leads off of the shift interupt switch and join them together my engine just kills therefore not allowing me to set my timing right. could it be a short?? the wire at teh igniton module that is supposed to be green and white is black on mine, but at the shift disconnect is grean and white and the other purple. but since joining the purple and green and white together shut down my engine could I be grounding out somewhere?? if so that could be the reason my ignition module is overheating causing my engine to shut down after a few minutes of driving. What are your thoughts?

 

[Rocky_Road]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

Hey Rocky Road, I'm having a similar problem getting my 1996 3.0LX engine into base timing mode. When I take the leads off of the shift interupt switch and join them together my engine just kills therefore not allowing me to set my timing right. could it be a short?? the wire at teh igniton module that is supposed to be green and white is black on mine, but at the shift disconnect is grean and white and the other purple. but since joining the purple and green and white together shut down my engine could I be grounding out somewhere?? if so that could be the reason my ignition module is overheating causing my engine to shut down after a few minutes of driving. What are your thoughts?

The wires that you jump at the distributor are both white.

The shift cutout wires are white/green and purple.

When you jump both of these that will place you in base timing mode.

If this 'kills' your engine, then it is probable that the timing was set without being in the correct base mode at some point...or your idle speed is set too low. If this were mine, I would hook up my timing light and jump the correct wires, and turn the engine over and see if I could get a reference point on the timing tab. With the distributor hold down loose, you should be able to rotate the distributor and try to get to the specified point. My guess is that the engine will fire, or you may have to undo the jump wires to get the engine running. Then you can do the wire jumping with the engine at idle...use the timing light...and get it dead on.

Happy boating!

P.S. The two white wires are in the picture that I posted, up at the top left corner.

 

[jminator2002]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

Ok, thank you for the tip, I just got home from work but eager to try it so I'm heading outside. I'll post my results shortly

 

[fossill]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

Take a jumper wire with aligator clips and run it from battery positive to the positive terminal on coil and see if it starts. Not familiar with your engine or setup but some engines have a start circuit in the ignition whereby more volts is applied to the coil on start and then reduced in run mode. From what you are saying I assume that power is not being applied to the coil when the key is turned to start. Might even be a key switch problem.

 

[jminator2002]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

Ok, just got in, I jumped the 2 white wires at the distributer, then jumped the wires from the cut off switch as described. Engine will not stay on. I left the 2 wires connected from the cut off switch and cranked the engine and tried to use my timing light to see if I could get a refernce point but my light will not come on unless engine is running. Back to square one. The main problem now is I can't make the engine stay on in order to put it in base timing mode. Could it be the module again?? I just bought the darn thing 2 days ago.

 

[jminator2002]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

Hey Fossil,

The engine starts, I just can't get it to stay on to put it in base timing mode so I can set the timing.

 

[jminator2002]

Re: Est Ignition Problem 1996 mercruiser 3.0LX ((((((PLEASE HELP)))))))

Re: Est Ignition Problem 1996 mercruiser 3.0LX ((((((PLEASE HELP)))))))

Sorry Fossil, my engine is a 1996 3.0 Merc LX

 

[indy440]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

I just looked through the service manual for this (since I have the same engine). Why doesnt the service manual say anything about jumping wires or switches?

 

[jminator2002]

Re: Est Ignition Problem 96 Mecrusier 3.0LX ((((((PLEASE HELP)))))))

Re: Est Ignition Problem 96 Mecrusier 3.0LX ((((((PLEASE HELP)))))))

Here is the procedure I am following, and if I try and start it with the cut off switch bypassed, it just won't start. If I connect them while it's running, the engine kills.

Mercruiser Marine Engine Timing Procedures
IMPORTANT: Failure to follow these timing procedure instructions will result in improper timing causing performance problems and possible severe engine damage.

3.0L Models Only

1. Connect timing light (91-99379 or similar) to No. 1 spark plug wire. Connect power supply leads on light to 12 volt battery. Refer to Specifications ? ?Engine Rotation and Firing Order,? for cylinder numbering and location.
2. Connect a shop tachometer to engine.
NOTE: Before starting engine make sure the timing tab and mark on damper are clean. Chalk or white paint on timing mark on damper may help visibility.
3. Install a jumper wire between the two WHITE leads on the distributor. Use Quicksilver 91-818812A1, or fabricate a jumper wire using a 6 in. (150 mm) section of 16 gauge wire with two male bullet terminal ends connected.
4. Bypass the shift interrupt switch, as follows:
A Disconnect wires at shift interrupt switch.
B Temporarily join the engine harness wires together.
IMPORTANT: Do not fail to reconnect these two wires to the shift interrupt switch when timing procedures are complete.
5. Start engine and run at normal idle speed.
6. Aim timing light at timing tab, located on the timing gear cover and crankshaft torsional damper. Check the timing. Refer to ?Specifications?.
7. Adjust timing by loosening distributor clamp and rotating distributor body as required until timing mark on damper or pulley lines up with the mark on tab specified in ?Specifications.? Tighten clamp and recheck location of timing mark.
8. Aim timing light at timing tab and recheck location of timing mark. Repeat Step 7 until timing is correct.
9. Stop the engine. Torque distributor hold down bolt to 20 lb. ft. (27 N.m).
10. Reconnect the two wires to the shift interrupt switch.
IMPORTANT: Be sure to remove jumper wire before returning engine to service, otherwise timing will not advance.
11. Remove jumper wire at distributor white leads.
12. With timing light still connected, start the engine and run at IDLE. Verify that timing did advance to 12o BTDC, plus or minus 2o. At 2400-2800 RPM maximum (total) advance is obtained and should be 27o BTDC (plus or minus 2o).
13. Stop the engine and remove the timing light.

 

[indy440]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

im looking at mercruiser service manual 13 for GM 4 cylinder motors and it doesnt say anything about the jumpers in the procedure. Interesting.

Im pretty sure the procedure you posted is the correct one though, this must not be the right manual or something.

 

[fossill]

Re: Est Ignition Problem 92 mercruiser 3.0 ((((((PLEASE HELP)))))))

I just looked through the service manual for this (since I have the same engine). Why doesnt the service manual say anything about jumping wires or switches?

Because its one of the tricks we used to use in the shop when I was an auto mechanic. When you got paid "flat rate" you didn't have a lot of time to kill troubleshooting out a problem. Usually we were only alowed .5hr for diagnostics.

 

[fossill]

Re: Est Ignition Problem 96 Mecrusier 3.0LX ((((((PLEASE HELP)))))))

Re: Est Ignition Problem 96 Mecrusier 3.0LX ((((((PLEASE HELP)))))))

Here is the procedure I am following, and if I try and start it with the cut off switch bypassed, it just won't start. If I connect them while it's running, the engine kills.

Mercruiser Marine Engine Timing Procedures
IMPORTANT: Failure to follow these timing procedure instructions will result in improper timing causing performance problems and possible severe engine damage.

3.0L Models Only

1. Connect timing light (91-99379 or similar) to No. 1 spark plug wire. Connect power supply leads on light to 12 volt battery. Refer to Specifications ? ?Engine Rotation and Firing Order,? for cylinder numbering and location.
2. Connect a shop tachometer to engine.
NOTE: Before starting engine make sure the timing tab and mark on damper are clean. Chalk or white paint on timing mark on damper may help visibility.
3. Install a jumper wire between the two WHITE leads on the distributor. Use Quicksilver 91-818812A1, or fabricate a jumper wire using a 6 in. (150 mm) section of 16 gauge wire with two male bullet terminal ends connected.
4. Bypass the shift interrupt switch, as follows:
A Disconnect wires at shift interrupt switch.
B Temporarily join the engine harness wires together.
IMPORTANT: Do not fail to reconnect these two wires to the shift interrupt switch when timing procedures are complete.
5. Start engine and run at normal idle speed.
6. Aim timing light at timing tab, located on the timing gear cover and crankshaft torsional damper. Check the timing. Refer to ?Specifications?.
7. Adjust timing by loosening distributor clamp and rotating distributor body as required until timing mark on damper or pulley lines up with the mark on tab specified in ?Specifications.? Tighten clamp and recheck location of timing mark.
8. Aim timing light at timing tab and recheck location of timing mark. Repeat Step 7 until timing is correct.
9. Stop the engine. Torque distributor hold down bolt to 20 lb. ft. (27 N.m).
10. Reconnect the two wires to the shift interrupt switch.
IMPORTANT: Be sure to remove jumper wire before returning engine to service, otherwise timing will not advance.
11. Remove jumper wire at distributor white leads.
12. With timing light still connected, start the engine and run at IDLE. Verify that timing did advance to 12o BTDC, plus or minus 2o. At 2400-2800 RPM maximum (total) advance is obtained and should be 27o BTDC (plus or minus 2o).
13. Stop the engine and remove the timing light.

disregard