2004 200HP Dies Coming Off Plane

[TMANN]

This is the same motor I swapped to EFI. Have since put everything back to orignal as I kept having issues. Motor has the same issue with carbs/efi.

2004 200hp 200XL Carb Serial # OT946483

Motor starts and idles great. Will blast off and run to WOT the first run no problem. When coming off WOT the motor stumbles at 3800rpm, tach instantly shows 2000rpm, then the motor dies.

It will instantly fire right back up then bogs trying to come on plane. Sometimes it will push thru and comes up running to wide open strong. I have checked spark when this happens and show all 6 firing with a timing light at idle. Also good resistance on the trigger coils hot.

Have tried different flywheel, stator, trigger, coils, and voltage regulators since I had them from another motor. Coils seem to be in spec with dva checks. Have also inspected exhaust tuner, rebuilt pulse pump, different plugs, and portable tank.

The control modules are different carb to efi so I have a hard believing that's my problem also.

As always thanks for any input other than unbolting this thing in 100' of water.

[leonreno]

Did the EFI form have an alternator or a stator? Have you tested voltage when this was happening? Wonder if it could be an over voltage issue somehow. Reeds checked I assume? Could be a timing problem also, have you done a link n sync?

[TMANN]

The efi motor is a 40a stator style setup also.Link sync was done and reset timing 4* to get the idle right. I reinstalled the original carb reed blocks which looked good.

I feel that it's a timing problem. I haven't had an extra person to work the throttle while I've had the problem for me to get a timing light on it and inspect the linkages.

The trigger doesn't appear to be binding.

I haven't checked voltage at the motor with a fluke when this happens. Volt meter at dash stays at about 13v.

I did try Turing off my main battery switch but no change still bogged and would not get over about 2200. Turned the switch back on and idled for a few mins. Then it came up on plane and brought me back to the dock, died off plane again, fired right back up and idled fine until on the trailer.

[EuropeanAM]

Check for timing bouncing around when it gets hot (helps to index off each cylinder so you can check all six... a timing tape will make this pretty simple).

Verify clean bias jumper between the two switchboxes (also verify whether you do or don't have a knock module).

Clean or replace grounds for both switchboxes.

Try a separate keyswitch harness

Monitor actual battery voltage at the battery when this is occurring to make sure voltage never exceeds 14.6 VDC.

[TMANN]

This is a cdm motor. I have checked to verify the bias circuit was functioning. All the grounds are reading .3 or less to different portions of the block.

I'm going to rig up a different harness and do some voltage checks when this snow clears. I'll get a timing tape ordered also.

Thanks for your help!

[JOE54]

mtr not starving for fuel is it / lean ?????

[EuropeanAM]

Might also try checking for fuel restriction (tee into fuel line as close to pulse pump as possible, monitor vacuum on line- it should not exceed 2.5" hg at ANY engine RPM or running condition).

Something as simple as a fuel tank vent that's restricted, plugged, or has liquid trapped in a low point of the hose can cause this.

[TMANN]

Took the boat for a run yesterday. Forgot my vacuum gauge, so that didnt get hooked up. Voltage stays around 13.3 to 13.6 normal or during the issue. When it shutdown I unhooked the tach signal, temp sensor, and the kill ckt. Motor ran perfect for 5-6 runs coming off plane then went back to same old thing. Maybe just a coincidence. Haven't tried a separate keyswitch harness yet, should have one soon.

[JOE54]

its possible to bypass key switch to isolate to mtr problem

[TMANN]

I pulled the voltage regulators off yesterday. They had been on the motor for about two weeks and originally came off the donor efi motor. I had swapped them as part of trying to rule things out but never actually tested them because i was on the water.

One of those regulators is certainly bad. The remaining 3 I have seem to test okay. Possibly one of the originals may break down when it's hot. Might not be my issue, but finally found something broke.

[JOE54]

fingers crossed , but skeptical

[TMANN]

Alright. Replaced the voltage regulators. Definitely charging better, consistent 13.7v. I replaced all the fuel lines and primer bulb. 3/8 all the way to the T. I had been running off a portable tank. Still stalls Coming slowly off plane. I can come of plane quickly no problem.

Another thing, this motor has always been jerky powering up. Not a smooth consistent climb up the rpm range. All the onions at once you hit 2300 or so. Not sure if that is normal for these motors. I've ran plenty of other motors but this is my first 2.5l

I have rebuilt the pulse pump once, and it appears fine off my vacumn gauge. Have you guys ever seen issues on the vacumn side of these pumps?

Again same issue carbs to efi so I'm trying to look at components that are consistent such as the feed lines, pulse pump, electronics, etc.

[leonreno]

What boat do you have and what prop do you have? What is the max speed and at what rpms?

[TMANN]

This is on a 208 Grady with a hardtop and bottom paint that looks like someone put on with a mop. Loaded full of fuel (82 gallons) it's running 38-39 with a 19p @5500 or so.

[JOE54]

i feel its electrical

[EuropeanAM]

Let me make sure I understand correctly: If you chop the throttle back to idle, it does NOT stall.

If you ease back slowly, it stalls.

[TMANN]

I thought so too Joe. I got back on the fuel side since the permanent lines needed to be changed anyway.

Yes sir Don. Chopped back, returns to idle purring like a kitten.

[EuropeanAM]

And you have done a COMPLETE Sync-n-Link since you put the carbs back on it?

Always the same trigger on the engine since narrowed down to this (very specific) complaint?

[TMANN]

Looking back thru the manual, I don't remember loosening the throttle blades or verifying the shutters @wot. I did align the throttle cam and roller, and verify timing. I never unbolted the carbs from the intake manifold, but possibly something has changed.

Trigger on the motor is brand new. Three different triggers, same symptom.

[leonreno]

I think he means when you removed the carbs to install the EFI and then reinstalled the carbs back.