MTD
Lawn & Garden Engine

Model # 4P90HUD Official MTD engine

Here are the diagrams and repair parts for Official MTD 4P90HUD engine, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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ALL PARTS
Showing 10 of 127 parts  |

Lawn & Garden Equipment Engine Spark Plug 951-10292
#19

Cylinder head diagram

Lawn & garden equipment engine spark plug

Part #951-10292

Replaced by #951-10292A

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Manufacturer substitution
This part replaces 951-10292. Substitute parts can look different from the original.
BEST SELLER
This item is not returnable
$5.88
63% OFF MSRP : $16.00
In Stock
Lawn & Garden Equipment Engine Oil Filter 951-12690
#123

Crankshaft & crankcase cover diagram

Lawn & garden equipment engine oil filter

Part #951-12690

Replaced by #490-201-Y010

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Manufacturer substitution
This part replaces 951-12690. Substitute parts can look different from the original.
BEST SELLER
$15.52
43% OFF MSRP : $27.00
In Stock
Lawn Tractor Air Filter 937-05122
#32

Air intake diagram

Lawn tractor air filter

Part #937-05122

BEST SELLER
$26.90
16% OFF Phone Price : $31.90
In Stock
Lawn & Garden Equipment Engine Carburetor Gasket 951-12261
#24

Carburetor assembly diagram

Lawn & garden equipment engine carburetor gasket

Part #951-12261

BEST SELLER
This item is not returnable
$6.35
14% OFF Phone Price : $7.35
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Lawn & Garden Equipment Engine Carburetor 951-05149
#25

Carburetor assembly diagram

Lawn & garden equipment engine carburetor

Part #951-05149

$147.58
6% OFF Phone Price : $157.58
In Stock
Lawn & Garden Equipment Engine Intake Manifold Gasket 951-12258A
#26

Air intake diagram

Lawn & garden equipment engine intake manifold gasket

Part #951-12258A

This item is not returnable
$6.35
14% OFF Phone Price : $7.35
In Stock
Lawn & Garden Equipment Engine Carburetor Insulator Gasket 951-12263
#22

Carburetor assembly diagram

Lawn & garden equipment engine carburetor insulator gasket

Part #951-12263

This item is not returnable
$6.35
14% OFF Phone Price : $7.35
In Stock
Lawn & Garden Equipment Engine Stator 951-12224
#60

Ignition & electrical diagram

Lawn & garden equipment engine stator

Part #951-12224

$83.26
24% OFF MSRP : $110.00
In Stock
Lawn & Garden Equipment Engine Voltage Regulator 951-12242
#100

Crankshaft & crankcase cover diagram

Lawn & garden equipment engine voltage regulator

Part #951-12242

$63.45
7% OFF Phone Price : $68.45
In Stock
Lawn & Garden Equipment Engine Valve Cover Gasket 951-12267
#3

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

Symptoms for gas walk-behind mowers

Choose a symptom to see related walk-behind mower repairs.

Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent…

Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel…

Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, ba…

Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key…

Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade…

Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up…

Repair guides for gas walk-behind mowers

These step-by-step repair guides will help you safely fix what’s broken on your walk-behind lawn mower.

How to replace a lawn mower transmission

How to replace a lawn mower transmission

Learn how to replace the transmission on your lawn mower if it's locked up or won't drive the wheels.…

Repair difficulty
Time required
 60 minutes or less
How to rebuild a lawn mower carburetor

How to rebuild a lawn mower carburetor

The carburetor mixes air with fuel to drive the piston. Rebuild the carburetor if it's clogged or leaks.…

Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower ignition coil on a flathead engine

How to replace a lawn mower ignition coil on a flathead engine

If the spark plug doesn't fire when you try to start the mower, you could have a defective ignition coil. Follow these s…

Repair difficulty
Time required
 30 minutes or less

Effective articles & videos to help repair your lawn & garden engines

Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…

What are the main components of a lawn mower?

What are the main components of a lawn mower?

Learn about the main parts of a lawn mower and when to replace parts.…