1999 200hp intermittent lose of power.

[Bob1101]

Hello all, I have a 1999 200hp mercury EFI that intermittently loses power. Idle is usually rough but motor never kills, first run of the day is usually good, boat gets on step and will run fine all day if I stay on step. Once off step and idle around, rough idle gets worse and then RPMs will only Max out at about 3200(in gear). This situation is sometimes easily corrected by placing motor in neutral and increasing throttle to 50-75%, RPMs bounce around at 3200 and then suddenly problem goes away and RPMs jump up, I quickly reduce throttle, put gear and idle is improved and boat easily gets on step once more. This problem is not always correctable by increasing RPMs as described. Entire fuel system has been checked, all fuel lines and filters have been replaced, fuel pressure is maintained at 35-38psi. Fuel injectors have been removed and cleaned, diaphram fuel pump rebuilt. With this said I do not believe I have a fuel problem? Ohms test on trigger approx 750, ohms test on stator approx 2100. Gap spark test varies from 1/4 inch to 9/16 inch on different cylinders. Oil alarm module,water sensor module, tps, air temp sensor and EFI/CEU all checked out. I would appreciate any comments/opinions. Thanks in advance.

 

[Iceman66]

Re: 1999 200hp intermittent lose of power.

Try to disconnect the two yellow wires from stator to rectifier/regulator and run it again.
If miss disappear, replace rectifier/regulator.

Remember to isolate the wires so they dont hit ground while running.

Check this link (page 89 and 90) : http://issuu.com/cdielectronics/doc...t.xml&backgroundColor=000000&showFlipBtn=true

 

[Bob1101]

Re: 1999 200hp intermittent lose of power.

Thanks Iceman66. Won't be able to run boat until this weekend, will let you know how it goes.

 

[Iceman66]

Re: 1999 200hp intermittent lose of power.

"This situation is sometimes easily corrected by placing motor in neutral and increasing throttle to 50-75%, RPMs bounce around at 3200 and then suddenly problem goes away and RPMs jump up"

DO NOT DO this , NEVER increase rpm that high without load(in gear), unless you WANT big internal damage inside your engine.

Let us know when you have tested again.

 

[CharlieB]

Re: 1999 200hp intermittent lose of power.

Spark test should ALWAYS produce a hot blue arc of at least 7/16 inch.

Any less and I begin to suspect the stator may not be producing enough voltage and I grab my DVA meter and start testing. Ohms test alone are indecisive, often failing to find sufficient fault to indicate the failing part. DVA test are very decisive.

The fact that performance comes and goes also tends to cast suspicion of the stator, it temperature windings may be shorting and loosing generation of voltage required. Running at high idle and no load may allow sufficient cooling the heat expanded windings shrink just enough they no longer contact.

Since there is NO RETURN on electrical parts you would be wise to prove the fault before ordering any electrical part.

DVA test the stator cold and record your readings. Repeat test once up to temperature. Retest immediately when the condition arises. Compare all readings to those found in the CDI Ignition Guide, if any numbers fail repeat that test to ensure the results, then order a new stator.

ISSUU - CDI Electronics Practical Outboard Ignition Troubleshooting by CDI Electronics

If your motor has an idle stabilizer connected to the Bias wire of the switchboxes, remove it, throw it away, reset WOT timing and readjust idle speed with idle timing.

 

[Bob1101]

Re: 1999 200hp intermittent lose of power.

CharlieB, thank you for the response but unfortunately I do not own a DVA multi meter. But I do have some interesting results. Iceman, I disconnected the 2 yellow wires from the stator as you suggested and noted no change, RPMs remained approx 3200 wot, in gear and under load. Next day while flushing motor on hose I noticed all 3 port cylinders were running cooler than usual. Laser type thermometer indicated temp of 97-98d on port cylinders and 115-120d on starboard cylinders . I turned motor off and disconnected 2 green wires from oil alarm module. These 2 green wires intersect the wires coming from trigger box to port coils(3). Restarted motor and within 2 min port temps were 120s and starboard temps were 140s (idle). Motor was also much improved audibly. Have never had an oil alarm sound, but do have the "beeeeeeeep beep beep beep" when key is turned on. Sounds like a faulty oil alarm module?

 

[Faztbullet]

Re: 1999 200hp intermittent lose of power.

Sounds more like you have injector/s flooding or MAP sensor problem.

 

[Bob1101]

Re: 1999 200hp intermittent lose of power.

Faztbullet, thanks for responding. Correct if I am mistaken but I believe the MAP sensor is located within the ECU which was recently sent off ,had drivers updated and I assume they inspected the MAP sensor. Injectors also recently cleaned. What is the preferred method of checking for flooding or MAP problems.

 

[Bob1101]

Re: 1999 200hp intermittent lose of power.

Faztbullet, thanks for responding. Correct if I am mistaken but I believe the MAP sensor is located within the ECU which was recently sent off ,had drivers updated and I assume they inspected the MAP sensor. Injectors also recently cleaned. What is the preferred method of checking for flooding or MAP problems.

 

[Iceman66]

Re: 1999 200hp intermittent lose of power.

What about the Engine Temp Sensor?
If to high temperature, it will limit timing to appr.3000rpm. Could it be defect?

 

[Faztbullet]

Re: 1999 200hp intermittent lose of power.

recently sent off ,had drivers updated and I assume they inspected the MAP sensor. Injectors also recently cleaned.

By whom as there is only several I trust?....What driver? the fuel pump driver?

 

[Bob1101]

Re: 1999 200hp intermittent lose of power.

Simon (California) is the person that serviced ECU. The company was Pro Marine and I do not remember what drivers were updated...Iceman, temperature switch checks out, no continuity at 215 degrees F. ?????

 

[CharlieB]

Re: 1999 200hp intermittent lose of power.

You really should invest in either a DVA meter or a DVA adaptor to use with any Volt/Ohm meter. With either of these you can check the stator and trigger voltages, also check switchbox output to each coil.

Usually when temp is down on one side of the motor it is an ignition fault NOT firing that side of the motor.

A simple spark test can show if one side is dead. This can be caused by an overheated stator failing to generate voltage for one side, or a bad Bias circuit on the OTHER switchbox blocking that switchbox from firing.

If you check when the condition occurs then do an immediate spark test. If no spark then switch the stator wires between the two switchboxes and repeat the spark test. If it is a heated stator it may cool and both sides work again but on your next occurrence it will be the other side with no spark.

 

[Bob1101]

Re: 1999 200hp intermittent lose of power.

Thanks for the info. CharlieB, I am starting to believe you are correct about the stator, and investing in a DVA meter. Unfortunately I will be busy at work until Tuesday of next week. Will update progress then.

 

[beatoangelo]

Re: 1999 200hp intermittent lose of power.

Bob I had just about the same problem with one of my 115 EFI motors. It turned out to be crude in the fuel vapor separator which was forming when my fuel actually boiled because of the proximity to the head. When the crude settled to the bottom of the separator it plugs the fuel flow. When I tipped my engine the dirt would move back from the fuel channel and all was well again. This material formed after two of the fuel filters! Drove me nuts. Had to disassemble the entire system to clean out the dirt and place a heat shield between the vapor separator and the cylinder head. Problem solved! Not sure if this is it or if you have the same fuel vapor separator set up but if you run into a wall it is worth a try to see if there is anything in the separator.

 

[Bob1101]

Re: 1999 200hp intermittent lose of power.

Beatoangelo, thanks for the reply but I do not think I have a fuel problem. I have a fuel pressure gauge temporarily installed. Pressure is a steady 36psi. I also have a clear fuel filter mounted between high pressure fuel pump and fuel rail to check for air bubbles. No air is ever visualized. I have a DVA adapter ordered and should receive it tomorrow. I believe this will help me diagnose the problem.

 

[CharlieB]

Re: 1999 200hp intermittent lose of power.

CharlieB, thank you for the response but unfortunately I do not own a DVA multi meter. But I do have some interesting results. Iceman, I disconnected the 2 yellow wires from the stator as you suggested and noted no change, RPMs remained approx 3200 wot, in gear and under load. Next day while flushing motor on hose I noticed all 3 port cylinders were running cooler than usual. Laser type thermometer indicated temp of 97-98d on port cylinders and 115-120d on starboard cylinders . I turned motor off and disconnected 2 green wires from oil alarm module. These 2 green wires intersect the wires coming from trigger box to port coils(3). Restarted motor and within 2 min port temps were 120s and starboard temps were 140s (idle). Motor was also much improved audibly. Have never had an oil alarm sound, but do have the "beeeeeeeep beep beep beep" when key is turned on. Sounds like a faulty oil alarm module?

The oil alarm module compares spark impulses to impulses of the rotation sensor on the oil pump. When it 'sees' a difference it sounds the oil alarm.

I still think you need to do a simple spark test, with and without the oil module green wires connected. If there is reduced spark with the module connected then I would begin to suspect the module defective.

Have you ran the boat with these wires disconnected? Did this restore performance?

 

[Faztbullet]

Re: 1999 200hp intermittent lose of power.

Idle is usually rough but motor never kills, first run of the day is usually good, boat gets on step and will run fine all day if I stay on step. Once off step and idle around, rough idle gets worse and then RPMs will only Max out at about 3200(in gear). This situation is sometimes easily corrected by placing motor in neutral and increasing throttle to 50-75%

Classic symptom of overrich due to injector/s problem .

 

[Bob1101]

Re: 1999 200hp intermittent lose of power.

Faztbullet, recently removed injectors and sent them to "Injector rx" in Houston. They tested, cleaned and retested. Results where good. This had no change in engine performance. CharlieB, spark test revealed the following. No spark on any cylinder at 7/16 gap; spark noted on all 3 starboard cylinders at 5/16 gap; spark noted on port cylinders at 1/4 gap and as low as 3/16 on cylinder #4.(#4 cylinder= port middle cylinder??) Audible change noted when starboard plug wires removed, no audible change when port plug wires removed. Port cylinders not firing.....also, ran boat with green wires from oil alarm module removed and results were questionable. First run of day motor running bad (exactly as explained earlier) with green wires connected. Disconnected green wires and after increasing rpms in neutral problem gone and motor ran well. Ran motor for 30 min stop and go and remained good. Connected green wires ( attempting to reproduce problem) and motor ran fine for an hour and then problem returned....????? I finally received my DVA adaptor today and plan to check and post peak voltage tomorrow . Any specific instructions on this would be appreciated. Currently researching this and detailed info not readily available. Thanks in advance...

 

[CharlieB]

Re: 1999 200hp intermittent lose of power.

Get the CDI Ignition Guide

ISSUU - CDI Electronics Practical Outboard Ignition Troubleshooting by CDI Electronics

Follow their easy directions to the letter.

The stator 'may' be getting weak, not generating sufficient voltage for a 7/16 hot blue arc.

The DVA will prove one way or another.

Is there an idle stabilizer module wired into the White Bias wire of the switchboxes? If so, REMOVE it completely, then retest everything. You will need to reset your WOT Ignition timing to 21 degrees while cranking. Some say 23, I like 21 with the rotten fuel we get.

Always remember there is NO RETURN on electrical parts. That DVA meter will decide, just test correctly, retest to confirm before ordering any parts.