225 EFI Mercury that won't turn more than 4600-4800 RPM's

[StarcraftSS]

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I've checked the coils they seem to be fine

A bit vague....how did you test them? Odd that the shop would clean injectors without checking for another cause(s).
How did the symptoms(lower RPMs) begin...suddenly or over a period of time?

[5fishon]

Don, was I supposed to hook both them grounds to the 8mm bolt on the cdm the one on top we hooked to the coil plate where the other grounds were I didn't pick up rpm's but I did gain 7 mph I got 55.3 mph out of her

[5fishon]

Suddenly but they would come back every now and then Im still only getting 4600 rpm's but gain 7-8 mph got 55mph out of her today

[5fishon]

I really appreciate all the help you guys have given me with this issue hope maybe my findings will help someone else thanks everyone

[5fishon]

StarcraftSS I bought a new coil and replaced one with the new one there was no change so I swapped out the next one and so on

[Mod4712]

Does it have a new fuel filter, What about your filter on the hp fuel pump inside the vst

[EuropeanAM]

Suddenly but they would come back every now and then Im still only getting 4600 rpm's but gain 7-8 mph got 55mph out of her today

First ground SHOULD have been on the coil PLATE where the other grounds attach.

Try a different tach. You're not getting 7 more MPH at the same RPM... I suspect that tachometer is not functioning properly.

[5fishon]

First ground SHOULD have been on the coil PLATE where the other grounds attach.

Try a different tach. You're not getting 7 more MPH at the same RPM... I suspect that tachometer is not functioning properly.

Don, just want to thank you for all the information and help you have given us on this matter very grateful

[Rich Z]

Battery and charging voltage good?

[44Mag]

I had a very similar issue with my 2000 225 EFI, poor holeshot and would only rev to around 4600-4800 RPM. After trying many things and rebuilding the entire fuel system, I checked the wiring under the flywheel to the stator and found that the wiring crimps had come apart (making poor contact) in the harness. I had spark on all 6 cylinders, but under a load it was just not enough. Repaired the wiring and it was good as new! It is worth a look if you have run out of things to look at, and certainly easier than pulling a powerhead. I am unsure if these crimps were factory or a repair made by the previous owner.

[Yanky Bob]

So was your problem solved for this top end power loss? If so, what was it?

[5fishon]

No have not found the problem yet still searching all help is greatly appreciated last task was we took the flywheel off and checked the stator didn't find any bad or broken wires but a few seem to wiggle a tad not sure if that's normal or not I am wondering if it's not getting a good connection wouldn't think they should move at all with the 25 p prop I got back from Marks I did get 5000 rpm's @. 50 mph I'm about ready to give up on it to be honest I'm very happy with the prop that Marks did for me it's bad ass great bow lift he's the man to send your prop to if you want it done right

[EuropeanAM]

Still using that same questionable tachometer?

[5fishon]

Yes sir I believe it's working what I forgot to mention was I was running the prop I'd just got back from Mark's prop now I'm at 4800 @ 50 mph pulled flywheel and looked at stator a couple of the wires where they are attached to the stator move a little and the stator looked like it was rusty

[EuropeanAM]

Can you post a picture of the stator (questionable area)?