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MTD
Lawn & Garden Engine

Model # 4P90MUA Official MTD engine

Here are the diagrams and repair parts for Official MTD 4P90MUA engine, as well as links to manuals and error code tables, if available.

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Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.

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Model diagram and schematic

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ALL PARTS
Showing 10 of 173 parts  |
Lawn & Garden Equipment Engine Carburetor Float Bowl Gasket 951-11349
#CC

Carburetor diagram

Lawn & garden equipment engine carburetor float bowl gasket

Part #951-11349

Replaced by #951-11349A

?
Manufacturer substitution
This part replaces 951-11349. Substitute parts can look different from the original.
This item is not returnable
$5.64
| 
15% OFF Phone Price : $6.64
In Stock
Lawn Tractor Engine Manifold Gasket 951-12258
#130

Air intake diagram

Lawn tractor engine manifold gasket

Part #951-12258

Replaced by #951-12258A

?
Manufacturer substitution
This part replaces 951-12258. Substitute parts can look different from the original.
This item is not returnable
$6.35
| 
14% OFF Phone Price : $7.35
In Stock
Lawn & Garden Equipment Engine Flywheel Key 951-10307
#77

Crankshaft & crankcase cover diagram

Lawn & garden equipment engine flywheel key

Part #951-10307

Replaced by #751P10307A

?
Manufacturer substitution
This part replaces 951-10307. Substitute parts can look different from the original.
This item is not returnable
$3.22
| 
24% OFF Phone Price : $4.22
In Stock
Guide 951-12268
#150

Cylinder head diagram

Guide

Part #951-12268

This item is not returnable
$12.69
In Stock
Lawn Tractor Engine Sump Filter 951-12249
#100

Crankshaft & crankcase cover diagram

Lawn tractor engine sump filter

Part #951-12249

This item is not returnable
$6.35
| 
14% OFF Phone Price : $7.35
In Stock
Lawn & Garden Equipment Engine Valve Cover Gasket 951-12267
#144

Cylinder head diagram

Lawn & garden equipment engine valve cover gasket

Part #951-12267

This item is not returnable
$14.25
| 
12% OFF Phone Price : $16.25
In Stock
Linkage 951-12230
#59

Crankcase diagram

Linkage

Part #951-12230

This item is not returnable
$7.06
In Stock
Lawn & Garden Equipment Engine Carburetor Mounting Stud 951-12264
#139

Carburetor diagram

Lawn & garden equipment engine carburetor mounting stud

Part #951-12264

This item is not returnable
$9.65
| 
9% OFF Phone Price : $10.65
In Stock
Lawn & Garden Equipment Engine Exhaust Gasket 951-12271
#160

Muffler diagram

Lawn & garden equipment engine exhaust gasket

Part #951-12271

This item is not returnable
$10.83
In Stock
Lawn & Garden Equipment Engine Piston Ring Set 951-12275
#178

Crankcase diagram

Lawn & garden equipment engine piston ring set

Part #951-12275

This item is not returnable
$32.76
| 
15% OFF Phone Price : $38.76
In Stock

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