Need help?

Search OutdoorKing by entering Key Words Below

Who's Online Now
1 members (NormK), 126 guests, and 61 robots.
Key: Admin, Global Mod, Mod
Online Spare Parts

Online Store

Newest Topics
Greenfield Evolution III 10.5
by CJay - 19/07/24 12:34 AM
Villers engine numbers
by Bevan12666! - 17/07/24 06:43 AM
Victa SSA201A Catcher
by PK5 - 11/07/24 05:16 PM
Greenfield Anniversary 88 Idler Sprocket
by Guliyas - 05/07/24 04:55 PM
Looking for service manual Cox Conquest
by MrG6 - 30/06/24 07:11 AM
Mcculloch Super 100 brushcutter
by sirzur - 29/06/24 01:12 PM
Topic Replies
Greenfield Evolution III 10.5
by NormK - 21/07/24 02:01 PM
Briggs and Stratton problems 550EX O9P702-0127-H5
by maxwestern - 19/07/24 07:55 PM
Villers engine numbers
by maxwestern - 18/07/24 05:54 PM
Victa SSA201A Catcher
by NormK - 11/07/24 08:39 PM
Greenfield Anniversary 88 Idler Sprocket
by Guliyas - 08/07/24 06:31 AM
HORSE MOWER - Port Melbourne - c1910-1930
by Alan M - 04/07/24 08:43 PM
Looking for service manual Cox Conquest
by MrG6 - 30/06/24 07:11 AM
Mcculloch Super 100 brushcutter
by sirzur - 29/06/24 01:12 PM
666 The Beast
by maxwestern - 24/06/24 10:19 PM
Previous Thread
Next Thread
Print Thread
Rate Thread
Hop To
Joined: Oct 2020
Posts: 49
Likes: 8
Hi All lawnmower Petrol heads.

About 2 yrs ago I found a Rover Wayfarer with a 4 stroke Briggs engine on it.
The compression was hopeless( 25 pSi), so I put it away for another day). Well the time has come, and I have stripped it apart, taken out the piston, push rods, carby, flywheel, etc etc.
My assumption is that the poor compression is due to the rings being worn out, or the valves not sealing well enough.
I ordered new rings for it ( not the $90 Briggs ones), but the cheaper copy ones from China ($30)
The photo below shows both the old rings in silver and new rings in black. The question is why are they significantly different in circumference?
The rings are aligned in the top part of the image(beginning at the same spot), but by the time one passes around to the other end there is a difference of very close to 4 mm.
I get that the wear would be where it rubs on the barrel wall, but why the wear at the ends?

Attached Images
448AEB7B-FFDC-48ED-95FC-BE44D6B446DF.jpeg (100.83 KB, 67 downloads)
Briggs Rings
Last edited by twostroker; 27/10/21 05:13 PM. Reason: Grammar modifications
Joined: Dec 1999
Posts: 5,343
Likes: 30
Repair Junkie
Hi Twostroker,

What is the ring gap when they are in the cylinder?

[Linked Image]


Please do not PM me asking for support. Post on the forums as it helps all members not just the individual.
Joined: Jan 2015
Posts: 1,487
Likes: 23
AVB Offline
Plus it would hurt to have the engine numbers and the PN of the rings as some engine have multiple ring sets based on the date code. Then you still got to be careful of ordering after market parts.

And I do understand about the skyrocketing Briggs prices as they just raised them again this week at Power Distributors. This where I get my Briggs price file from for my auto manager system. They are also apparently having a hard time making parts available as several items I need are on long term back order. They may be stuck off the coast of California on a ship.

Joined: May 2010
Posts: 304
Likes: 22
Apprentice level 4
Comparing old rings to new ones is meaningless outside the engine. the only way to confirm if rings fit is to put them in the bore.

The old ones will be worn and will have lost heat treatment over the years of running. Similarly the new rings have not been heat treated to fit the new bore until it has run in so you are comparing an apple with a banana basically.

Also rings don't really wear at the gap, the gap increases as metal is worn off the circumference, and the ring gap grows as the spring opens further.

Moderated by  bigted, Bruce, CyberJack, Gadge, Mr Davis 

Link Copied to Clipboard
1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30 31
Comment Guidelines: Do post respectful and insightful comments. Don't flame, hate, spam.
Newest Members
slick50, Tek7TipTinkerer, Bevan12666!, TERENCE, Villiersman
16,838 Registered Users
Forum Statistics
Most Online2,545
Dec 23rd, 2019
OutdoorKing Showcase
20 Bucks from FB Marketplace
20 Bucks from FB Marketplace
by Return Rider, February 20
Victa Cortina 2 Shed Find
Victa Cortina 2 Shed Find
by Return Rider, January 25
My Rover Baron 45
My Rover Baron 45
by Maxwell_Rover_Baron, April 16
SHOWCASE - Precision Mowers - 2021
SHOWCASE - Precision Mowers - 2021
by CyberJack, April 14
SHOWCASE – Atco Rotary – Paul C - 2020
SHOWCASE – Atco Rotary – Paul C - 2020
by CyberJack, December 28
Powered by UBB.threads™ PHP Forum Software 7.7.5
(Release build 20201027)
Responsive Width:

PHP: 7.4.33 Page Time: 0.018s Queries: 24 (0.013s) Memory: 0.6766 MB (Peak: 0.7262 MB) Data Comp: Zlib Server Time: 2024-07-21 04:43:25 UTC
Valid HTML 5 and Valid CSS