OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Reel Lawn Mowers, Atco & Villiers etc. Scott bonnar 33 Roadside find

Hi, I recently picked up what I believe to be a Scott Bonnar model 33 lawnmower off the side of the road during a council rubbish collecfion.

I have absolutely zero mechanical knowledge currently but would like to restore it back to its former glory before using it to cut my lawn. Based on reading some posts here I believe it to be a mark 2 model as it has a belt and chain configuration.

The original engine I believe has been replaced with a briggs and stratton 475 series 148cc. It also has a Rover speed control switch. I will try to upload some pictures.

Although I haven't tried starting it yet, apart from the odd dents and scratches the mower seems to be in good condition for its age, except for a random bit of wire sticking out from the front of the engine.

My question is, what's the wire sticking out from the engine and where should I start in a restoration process from a complete novice prospective, I assume rust and dent removal would be the first steps before trying the mechanical side of things.



Kind regards
Mike

Hi Mike33,

That wire as shown in the parts list below it is the stop wire but you don't need to connect it as the throttle control on the motor has the stop connector there.

G'day Mike

Take lots of photos of the mower from all angles.

Identify missing, broken, or seized parts.

Make a list of what you need to replace or repair (nuts, bolts, bearings, paint, blades, etc.).

Check for historical manuals or diagrams online

This gives you a clear idea of scope — saves frustration later.

2️⃣ Clean and Degrease

Even before sanding or dent repair, give it a good clean:

Remove loose dirt, grass, and grease.

Use degreaser on the reel, gearbox, and handles.

Avoid soaking bearings and shafts yet — just clean the surfaces.

Pro tip: Cleaning now helps you see rust, dents, and cracks better.

3️⃣ Disassembly

Take the mower apart carefully.

Label each part or use ziplock bags for small screws/bolts.

Take more photos during disassembly — very helpful when reassembling.

Order tip for novices:

Remove handles and frame panels

Remove cutting reel and bed knife

Remove gearbox, wheels, and axle assemblies

Don’t force stuck parts — penetrating oil can help.

4️⃣ Cosmetic Work (Rust & Dents)

Yes, generally cosmetic first:

Rust Removal:

Light surface rust: wire brush, steel wool, or sandpaper.

Heavier rust: naval jelly, vinegar soak, or a wire-wheel attachment.

Powder-coated or painted surfaces: consider stripping old paint first (chemical stripper or sandblasting).

Dent Repair:

Small dents: hammer + dolly or soft mallet.

Big dents: consider body filler if it’s on painted panels (not critical for mechanical function).

Final Prep:

Sand all surfaces to smooth metal.

Wipe down with solvent before painting.

5️⃣ Mechanical Inspection

Once the cosmetic surfaces are sorted:

Check the reel bearings, wheel bearings, and gearbox.

Spin the reel by hand — is it tight or binding?

Inspect blade tips and bed knife. They can often be sharpened rather than replaced.

Grease and oil moving parts.

Replace any missing fasteners.

Pro tip: This is easier after paint is cured to avoid scratching new surfaces.

6️⃣ Painting / Finishing

Mask off mechanical parts like bearings, gears, and blade edges.

Primer → Paint → Clear coat if desired.

Let paint cure fully before reassembly.

7️⃣ Reassembly

Follow photos and part labels.

Lubricate moving parts as you go.

Adjust reel-to-bed knife clearance (Scott Bonnar mowers are famous for needing careful adjustment).

Test-roll the mower before using it on grass.

8️⃣ Testing

Start with a small patch of grass.

Check for:

Smooth reel rotation

Proper cut height

No unusual vibrations or squeaks



Take your time.

Use YouTube or mower forums for visual guidance — there are Scott Bonnar enthusiasts with step-by-step videos.

Document everything — even small steps help during reassembly.

If something looks rusty but structurally sound, you can sometimes clean, prime, and paint rather than replace.

Cheers
Max.