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View Full Version : 1996 Yamaha 75hp to 90 hp



Jstaff185
03-29-2020, 04:47 PM
Trying to figure out how they detune these motors every part I see for the intake is the same part number. Carbs main jets reeds. the plate and gasket between the carb and reeds is all the same part number they have a different exhaust manifold but I can't see a pic where the motor meets the lower casing there might be a restrictor in there any help please

Powerabout
03-29-2020, 06:47 PM
Trying to figure out how they detune these motors every part I see for the intake is the same part number. Carbs main jets reeds. the plate and gasket between the carb and reeds is all the same part number they have a different exhaust manifold but I can't see a pic where the motor meets the lower casing there might be a restrictor in there any help please
are the blocks the same part number?

Jstaff185
03-29-2020, 07:47 PM
For 1996 the 90hp and 75hp have the same crank case assembly

Jstaff185
03-29-2020, 07:58 PM
It seems to me there is something between the block and exhaust manifold but I would like to know more and be sure before I tear it apart.

Powerabout
03-29-2020, 08:02 PM
Never heard of blocking exhaust to restrict hp.
Normally carb venturi size so carbs are different part number.

Jstaff185
03-29-2020, 10:06 PM
Never heard of blocking exhaust to restrict hp.
Normally carb venturi size so carbs are different part number.
Well carb part numbers and jet numbers are the same when I look online so either Yamaha is hiding something or you didn't read my original post

Powerabout
03-30-2020, 12:09 AM
Well carb part numbers and jet numbers are the same when I look online so either Yamaha is hiding something or you didn't read my original post

On boats.net you get different carb part number.
I did notice the 5 digits are the same in the middle of the part number but prefix and suffix different.

Jstaff185
03-30-2020, 06:11 AM
I have a p75tlhu and the carb numbers are the same as the 90 hp on boats.net

Powerabout
03-30-2020, 06:45 AM
I have a p75tlhu and the carb numbers are the same as the 90 hp on boats.net
yep your right, I would bet one of them is wrong?

Jstaff185
03-30-2020, 07:13 AM
Crowly marine has the same carbs listed as well I'll have to check Someone's 90hp out and see if there carb numbers match mine

Fast Fred
03-31-2020, 10:47 AM
Got a set of round bowl 90 cards 250 plus the ride

Jstaff185
03-31-2020, 10:55 AM
What's the part number on the side of the carb body

Fast Fred
03-31-2020, 11:43 AM
The number on the mounting flange is 6h1

Fast Fred
03-31-2020, 11:44 AM
It’s not a part number it’s a model number

Fast Fred
03-31-2020, 11:50 AM
Think the part number is 11303

88workcar
05-06-2020, 04:33 AM
The reed "stops" are closed and the tuner pipe has a restriction. That is the two big items.