2.5 carbs

[redsnapper386]

guys is there any such thing as the best carbs to run on a 1993 2.5 200 v6 im running wmh 33-c and cannot get these to idle right ive also tried different jets heres some problems-surging up to 300 rpms at idle same sureging when adding throttle up to 3000 rpms the motor shuts down at 4200 rpms as if it has a governor installed i recently rebuilt motor with all new parts all electrics test good by ohms and dva im useing clear fuel lines to watch fuel flow all is good fuel pump rebuilt carbs all rebuilt 3 times no leaks fuel tank cleaned tested for air leaks i feel that these carbs are wrong for the motor even though they came from merc factory oh timeing is set 25 deg max and 4 deg idle air screws are 2/1/4 turns out this is about all i can say at this time need advice just to add the blck is stamped EE which is for low end torque for heavy boats this is from merc tecks thanks

[OnPad]

Have you looked at your reeds?
Done any testing of electrical components, like stator and switchboxes?
Checked for air leaks at bleed lines, and crank seals?

What flavor of boat and prop is this mounted on?

[redsnapper386]

Have you looked at your reeds?
Done any testing of electrical components, like stator and switchboxes?
Checked for air leaks at bleed lines, and crank seals?

What flavor of boat and prop is this mounted on?

this is a complete rebuild with new every thing bleed lines ect reeds are new ccm and stuffers the boat is a 24 ft off shore deep v with 14x19 stainless props i will be testing with 17 inch props also my manual says max wot rpms is 5000-5400 will test coils next also new and re check timeing thanks

[OnPad]

1993 factory carbs listed as wmh-21
1994-5 factory carbs listed as wmh-34
Your carbs came on 94-95 175 according to my service manual.
I currently own two carb motors, neither are mounted on a boat. One is 94-95 model listed above. It didn't idle all that well, for the year I had it in service, replaced it with efi.
I also have a 1982 225 with wh-20 carbs. Supposedly a good carb for hot rod application. Maybe some day I will find out. I believe there are a few others in the preferred camp.

Still sounds like a air leak, or possibly a float bowl running dry, if it's surging.

[redsnapper386]

1993 factory carbs listed as wmh-21
1994-5 factory carbs listed as wmh-34
Your carbs came on 94-95 175 according to my service manual.
I currently own two carb motors, neither are mounted on a boat. One is 94-95 model listed above. It didn't idle all that well, for the year I had it in service, replaced it with efi.
I also have a 1982 225 with wh-20 carbs. Supposedly a good carb for hot rod application. Maybe some day I will find out. I believe there are a few others in the preferred camp.

Still sounds like a air leak, or possibly a float bowl running dry, if it's surging.

yep surgeing tack bounceing at idle from 1000-1400 radically no adjustments help at all things clear up at 3000 rpms should i try bigger main jets now 66 or idle jets will take carbs off again and try a flow test some way useing gas thanks

[OnPad]

Wmh-33 main .064 /idle air .048
Wmh-34 main .066 on cyl 1&2 .064 cyl 3,4,5,6 /idle .046
I believe the two carbs above are the same except for the difference's listed. Would think your carbs would run a 200 fine the way they are. Sounds like a air leak. You should also turn down your timing, you should be idling at 650rpm. At the speeds your claiming, shifting becomes a problem.

Do you still have your idle stabilizer ?

[mach351]

Don’t touch the jetting….you have an issue somewhere else.