Miss/ misses on a 97 200 hp Ocean Pro

dingbat

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My mechanic is trouble shooting a problem on my motor and just isn’t getting anywhere. He says he’s never seen anything like this in all his years in the repair business.

The symptoms are as follows: There is an intermittent miss in the #1 cylinder at idle and an all out miss in #1 and #5 cylinders once you reach 5K rpm. Everything else in between seems to check out OK.

He’s swapped out the power pack, the stator seems to check out and the magnets on the fly wheel seem to be in good condition. Now he’s guessing maybe it’s the timer base. Any ideas?
 

Walker

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Re: Miss/ misses on a 97 200 hp Ocean Pro

Clean the coil grounds. Is this a saltwater motor??
 

dingbat

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Re: Miss/ misses on a 97 200 hp Ocean Pro

Yes, It's a saltwater motor.

All of the coils and ground plates have been replaced.

Looking at the manual it appears that there is a charge coil for each bank. Wondering if it's not a charge coil going out although he says the stator assembly checks out.
 

Walker

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Re: Miss/ misses on a 97 200 hp Ocean Pro

Have you done a spark test while its acting up?
 

dingbat

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Re: Miss/ misses on a 97 200 hp Ocean Pro

That's how he finally narowed down the problem. It will drop #1 at idle from time to time but drops out both at #1 and #5 constantly at 5K and above. Everything in between seems OK
 

clanton

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Re: Miss/ misses on a 97 200 hp Ocean Pro

Check the engine wiring harness where it connects to the control harness. The connector with the black yellow wire, sometimes this will arc to the black wire causing the misfire. You will see the the burnt spot on the inside of the connector. You can test the pack, stator, and timer base with a meter, no guessing. There are 2 charge coils for the ignition and a charge coil for the logic in the pack. The first test should be the pack output to the ignition coils, if this is OK, check the timer base output, 2 sets of sensors 1 for quickstart and 1 for run. Follow instruction in OMC manual. The basic test are done at cranking rpms, then retest with engine running at the misfire rpms.
 

dingbat

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Re: Miss/ misses on a 97 200 hp Ocean Pro

Quick update.
The power pack and timerr base have since been replaced with the same results. Everything else disabled at the power pack. Noticed that the key had been sheared at one time so we cleaned up the shaft and retorque the flywheel, The problem now shows up on both banks so messing with the flywheel has seemed to only worsen the problem. New flywheel on the way so we'll see what happens.
 

clanton

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Re: Miss/ misses on a 97 200 hp Ocean Pro

You said everthing else disabled at powerpack. You have 2 charge coils and 1 power coil supplying power to the pack, if you leave the power coil disconnected, the pack logic will not work. The logic shifts the timer sensors from start to run. Flywheel may be problem, but you should be testing output voltage with meter.
 

dingbat

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Re: Miss/ misses on a 97 200 hp Ocean Pro

Thanks for the comeback. Any input at all is appreciated at this point.

All voltages out to coils are within specification and have been verified using two different sets of meters for good measure. Some anomalies where seen thus the swapping of the power pack and timer base. Have not messed with the stator as of yet since all the voltages from that assembly seem to check out.

At idle #1 has an intermittent miss and then every thing runs normally up to 5K RPM and everything goes haywire. The miss was originally confined to #1 and #5 cylinders but has since deteriorated and now affects the opposing bank of cylinders as well
 

clanton

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Re: Miss/ misses on a 97 200 hp Ocean Pro

What is the power coil output at cranking rpm? What are the timer sensors output voltage and ohms. Remember there are 12 timer sensors, 6 for starting, 6 for run. Power pack output to coil? charge coil output.
 
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Re: Miss/ misses on a 97 200 hp Ocean Pro

seahunter said:
My mechanic is trouble shooting a problem on my motor and just isn’t getting anywhere. He says he’s never seen anything like this in all his years in the repair business.

The symptoms are as follows: There is an intermittent miss in the #1 cylinder at idle and an all out miss in #1 and #5 cylinders once you reach 5K rpm. Everything else in between seems to check out OK.

He’s swapped out the power pack, the stator seems to check out and the magnets on the fly wheel seem to be in good condition. Now he’s guessing maybe it’s the timer base. Any ideas?
 
Joined
Nov 26, 2006
Messages
6
Re: Miss/ misses on a 97 200 hp Ocean Pro

Hello I had the same problem and found rpm dropping while trimming. the problem wound up being a bad flywheel. the inner trigger magnet was bad.
 

dingbat

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Re: Miss/ misses on a 97 200 hp Ocean Pro

clanton said:
What is the power coil output at cranking rpm? What are the timer sensors output voltage and ohms. Remember there are 12 timer sensors, 6 for starting, 6 for run. Power pack output to coil? charge coil output.
My mechanic has done all the testing and didn’t relay specifics but he's assured me that everything tests out within spec and that he has the required 130-150V at the coils. From what I understand of the system I’d be looking awfully hard at the stator assembly but he seems to have passed on that stating it checks out OK.

If this fly wheel doesn’t resolve the issue he’s now swapped out everything with the exception of the stator.

The cost just keeps going up and my fish are moving sourth... fast :(
 

clanton

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Re: Miss/ misses on a 97 200 hp Ocean Pro

The power coil doesn`t make 130/150 volts at cranking rpms.
 

JUSTINTIME

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Sep 2, 2006
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Re: Miss/ misses on a 97 200 hp Ocean Pro

i heard flywheel is key but do not know

if u get volts to coils then stator is OK

it goes stator=powerpack (CDI)=coils
triggers fire the coils
 

dingbat

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Re: Miss/ misses on a 97 200 hp Ocean Pro

Installed a new flywheel. Problem solved.8)8)
 

Captain NEMO

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Dec 16, 2006
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Re: Miss/ misses on a 97 200 hp Ocean Pro

wow great to here that....
good job....now go catch those fish and post up some pictures..
 

dingbat

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Re: Miss/ misses on a 97 200 hp Ocean Pro

yamamarinetech40 said:
Wow, I wish I was YOUR mechanic....would love a pool.

4 hours of labor and a fly wheel at cost doesn't buy much of a pool the last time I checked. o:)
 
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