1993 evinrude 90hp v4 issues

[Penny_pincher]

I'm new to this so hopefully this gets to the right place. Cause I need some help.
I have a 1993 evinrude 90 that I have been having troubles with since day one of owning it.
Known problems:
1. Under-power (have to put weight in the front of the boat to plane out my 16ft bass boat)
2. Cylinders 2 and 4 are running warmer than 1 and 3 (im guessing 20-40) degrees difference

Things that have been done or replaced:
1. New fuel lines and filters
2. Compression check on all 4 cylinders is above 100 psi
3. New cdi
4. Carbs tore apart and jets and bowls cleaned
5. New plugs
6. New coils
7. New primer bulb (also tried using a 5-7 psi 12v inline fuel pump in place of primer bulb)
I'm sure I'm forgetting something parts wise.
Also no misfires on any of the cylinders or alarms coming from boat.

Only thing I can think is exhaust problem, or stator not working properly. I added a squirt of ether at fuel throttle and engine seem to die down like to much fuel... help this thing is driving me nuts.
Thanks

 

[Penny_pincher]

Also I forgot timing is set to 6-7 degrees before tdc at idle speed in water

 

[racerone]

Orange / blue stripe wires on the top coils ??

 

[ct1762@gmail.com]

usually the starboard side runs warmer, since the head is higher up and gets water last. i'd take the head off the port side and make sure the deflectors and passages are clear

 

[Penny_pincher]

Yes blue striped wires are going to the top coils. And I had heads off this summer to replace head gaskets due to over head also replaced water jacket gaskets and cleaned ports in heads. Could the cooling not being more equal on both sides be causing problems with pulls out of the hole. Cause it doesn't matter if engine is cold or warmed up to operating temp I still have the same under power issue. Once on plane boat will run about 4-4500 rpm with a top speed of about 32 which still seems slow for a 90hp motor on a 16ft boat

 

[ct1762@gmail.com]

i see no mention of the water pump, thermostats and poppet valve grommets. that stuff all needs to be in tip top shape! what model/brand of boat is it, and what prop is on it?

 

[Penny_pincher]

Waterpump was replaced this year. Never have messed with the thermostats. Im not even sure how to get them out. The bolts hit the housing for the engine before they come out. And im not quite sure about the poppet grommets you mention?

 

[ct1762@gmail.com]

the grommets and t stats are in that housing. you have to remove the lower motor pan bolts to get enough room, although i've gotten them out without even doing that with a long flex-head ratchet. the cooling hoses need to be popped off as well, but this work is an absolute must!