Easy
15-30 minutes
Lock Nut (m8) 678189001
OEM part for: Ridgid, Ryobi, Homelite, Husky
Part Number: 678189001
$3.99
Usually ships in 7 - 12 business days
Leaves our warehouse within 7 - 12 business days
Compatibility
This part will fit the following 31 machines
Ridgid
RD80770 3800 PSI / 4.0 GPM Commercial Pressure Washer View Diagrams & Manuals
RD80971 Gasoline Pressure Washer View Diagrams & Manuals
Ryobi
RY80030 Gasoline Pressure Washer View Diagrams & Manuals
RY80030A Gasoline Pressure Washer View Diagrams & Manuals
RY80518 Pressure Washer View Diagrams & Manuals
RY9C3501 RY9C3501 Digital Inverter Generator Mfg. No. 090930281 View Diagrams & Manuals
Homelite
UT902250 2250 Watt Generator View Diagrams & Manuals
HP3127S Gasoline Pressure Washer View Diagrams & Manuals
HU80520 Pressure Washer View Diagrams & Manuals
HU80522 Pressure Washer View Diagrams & Manuals
HU80530 Pressure Washer View Diagrams & Manuals
HU80931 Pressure Washer View Diagrams & Manuals
HU80531 Pressure Washer View Diagrams & Manuals
HU2250 Watt Generator View Diagrams & Manuals
HU22511 Generator View Diagrams & Manuals
PS903500 3,500 Watt Generator View Diagrams & Manuals
PS903500A 3,500 Watt Generator View Diagrams & Manuals
UT80516 2200 PSI Gasoline Pressure Washer View Diagrams & Manuals
UT902211 2250 Watt Generator View Diagrams & Manuals
PS80519 (090079257) Powerstroke Pressure Washer View Diagrams & Manuals
PS80516B Powerstroke Pressure Washer View Diagrams & Manuals
PS80519 Powerstroke Pressure Washer View Diagrams & Manuals
PS80517 Pressure Washer View Diagrams & Manuals
PS80519B (090079293) Powerstroke Pressure Washer View Diagrams & Manuals
Husky
HU80520 Pressure Washer View Diagrams & Manuals
HU80522 Pressure Washer View Diagrams & Manuals
HU80530 Pressure Washer View Diagrams & Manuals
HU80931 Pressure Washer View Diagrams & Manuals
HU80531 Pressure Washer View Diagrams & Manuals
HU2250 Watt Generator View Diagrams & Manuals
HU22511 Generator View Diagrams & Manuals
Show More Compatible Models
This item works with the following types of products:
- Pressure Washer Parts
- Generator Parts
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Customer Repair Instructions ?
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part.
The water pump on my pressure wash failed
Michael - October 19, 2022
Tool Type
Pressure Washer
Difficulty
Easy
Time
15-30 minutes
Tools Used
Socket set, Wrench Set
At first I thought the Pressure Relief valve failed. I bought and replaced it. Same problem, steam came out of the valve, no pressure at the nozzle.
The new pump was a direct bolt-up. I bought new bolts and lock nuts as well.
1. Removed three bolts holding the pump to the motor/frame. The pump slipped right off.
2. Removed the Woodruff key from the old pump and installed in the new. The Woodroff key fits in slots in both the driveshaft and the pump and locks them together.
3. Removed and the Pressure Relief valve from the old pump and installed it on the new.
4. The new pump slipped right onto the driveshaft. Aligned bolt holes and inserted the new bolts bottom to top and threaded the new locknuts onto them. Tightened the nuts after all the nuts were threated.
5. Job done! The pressure washer started immediately and produced water pressure at the nozzle.
The new pump was a direct bolt-up. I bought new bolts and lock nuts as well.
1. Removed three bolts holding the pump to the motor/frame. The pump slipped right off.
2. Removed the Woodruff key from the old pump and installed in the new. The Woodroff key fits in slots in both the driveshaft and the pump and locks them together.
3. Removed and the Pressure Relief valve from the old pump and installed it on the new.
4. The new pump slipped right onto the driveshaft. Aligned bolt holes and inserted the new bolts bottom to top and threaded the new locknuts onto them. Tightened the nuts after all the nuts were threated.
5. Job done! The pressure washer started immediately and produced water pressure at the nozzle.
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Our customer service team are at the ready daily to answer your part and product questions. We have a dedicated staff with decades of collective experience in helping customers just like you purchase parts to repair their products.
All our part reviews are solicited directly from other customers who have purchased this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
All our customer repair instructions are solicited directly from other customers just like you who have purchased and replaced this exact part. While we moderate these reviews for profanity, offensive language or personally identifiable information, these reviews are posted exactly as submitted and no alterations are made by our team.
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