Can’t find your part?   Contact us:
+1-309-603-4777
Sears Parts Direct
Tips to find your model number
Orders

  • Keep track of the models you own in your profile

    Sign in or Register to view or add models

Schedule a repair
Hydro-Gear
Engine & Drivetrain

Model # 321-0510 Official Hydro-Gear hydro-gear transaxle

Here are the diagrams and repair parts for Official Hydro-Gear 321-0510 hydro-gear transaxle, as well as links to manuals and error code tables, if available.

There are a couple of ways to find the part or diagram you need:

  • Click a diagram to see the parts shown on that diagram.
  • In the search box below, enter all or part of the part number or the part’s name.

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

We encourage you to save the model to your profile, so it’s easy to access parts and manuals for your appliance whenever you log in.

For DIY troubleshooting advice and repair guides, visit our repair help section.

Model diagram and schematic

SEARCH WITHIN THIS MODEL

?

This is the number corresponding to the part on the diagram / schematic

Search
ALL PARTS
Showing 10 of 96 parts  |
Retaining Ring 170405
#53

Hydro transaxle diagram

Retaining ring

Part #170405

Replaced by #583041601

?
Manufacturer substitution
This part replaces 170405. Substitute parts can look different from the original.
This item is not returnable
$6.83
In Stock
Lawn Tractor Transaxle Sealant 178322
#6

Hydro transaxle diagram

Lawn tractor transaxle sealant

Part #178322

$76.42
In Stock
Compression 170417
#71

Hydro transaxle diagram

Compression

Part #170417

Replaced by #583001401

?
Manufacturer substitution
This part replaces 170417. Substitute parts can look different from the original.
This item is not returnable
$8.54
In Stock
Friction Stud 170421
#76

Hydro transaxle diagram

Friction stud

Part #170421

Replaced by #582998501

?
Manufacturer substitution
This part replaces 170421. Substitute parts can look different from the original.
$13.69
In Stock
Miter Gear 150793
#38

Hydro transaxle diagram

Miter gear

Part #150793

Replaced by #583244201

?
Manufacturer substitution
This part replaces 150793. Substitute parts can look different from the original.
$131.96
In Stock
Tapping Bolt 178334
#88

Hydro transaxle diagram

Tapping bolt

Part #178334

Replaced by #587798701

?
Manufacturer substitution
This part replaces 178334. Substitute parts can look different from the original.
This item is not returnable
$5.31 | 
16% OFF Phone Price : $6.31
In Stock
Spacer #2371 170411
#65

Hydro transaxle diagram

Spacer #2371

Part #170411

Replaced by #583001201

?
Manufacturer substitution
This part replaces 170411. Substitute parts can look different from the original.
This item is not returnable
$11.97
In Stock
Miter Gear 150792
#37

Hydro transaxle diagram

Miter gear

Part #150792

Replaced by #583244201

?
Manufacturer substitution
This part replaces 150792. Substitute parts can look different from the original.
$131.96
In Stock
Expansion 173165
#128

Hydro transaxle diagram

Expansion

Part #173165

Replaced by #583057701

?
Manufacturer substitution
This part replaces 173165. Substitute parts can look different from the original.
$73.31
In Stock
Bearing.30x5 173159
#19

Hydro transaxle diagram

Bearing.30x5

Part #173159

Replaced by #532150771

?
Manufacturer substitution
This part replaces 173159. Substitute parts can look different from the original.
$39.98
In Stock

Symptoms for gas line trimmers

Choose a symptom to see related grass line trimmer repairs.

View all

Why does my gas line trimmer run rough?

Main causes: stale fuel, clogged fuel filter, faulty spark plug, clogged air filter, cracked fuel lines, clogged carbure…

Read more

Why won't my gas line trimmer start?

Main causes: stale fuel, cracked fuel lines, dirty carburetor, bad spark plug, worn piston rings…

Read more

Why does my gas line trimmer leak gas?

Main causes: cracked fuel lines, bad carburetor seals, leaky fuel tank cap, damaged fuel tank…

Read more

Repair guides for gas line trimmers

These step-by-step repair guides will help you safely fix what’s broken on your grass line trimmer.

View all
How to rebuild a line trimmer carburetor

How to rebuild a line trimmer carburetor

If the line trimmer engine won't start even though there's fuel in the tank, the carburetor could be the problem. Follow…

Read more
Repair difficulty
Time required
 15 minutes or less
How to replace a line trimmer carburetor

How to replace a line trimmer carburetor

If the line trimmer won't start even though there's fuel in the tank, the carburetor could be the problem. Follow these …

Read more
Repair difficulty
Time required
 15 minutes or less
How to replace a line trimmer fuel line

How to replace a line trimmer fuel line

The fuel line on a grass line trimmer deteriorates with time and eventually can split or crack. You can replace it yours…

Read more
Repair difficulty
Time required
 15 minutes or less

Articles and videos for gas line trimmers

Use the advice and tips in these articles and videos to get the most out of your grass line trimmer.

View all
How to enjoy all the online benefits we offer on our Sears PartsDirect website

How to enjoy all the online benefits we offer on our Sears PartsDirect website

Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier.…

Read more
Solving 3 common problems with line trimmer cutting lines

Solving 3 common problems with line trimmer cutting lines

Follow these tips to prevent the cutting line on your grass line trimmer from breaking or feeding out too much or too li…

Read more
How to replace a line trimmer fuel line video

How to replace a line trimmer fuel line video

Follow the steps in this video to replace a leaking fuel line in a line trimmer.…

Read more

Parts & More