The Mono SL-245 was a mid-1960s American chainsaw built by Mono Manufacturing Co. of Springfield, Missouri. Mike Acres’ site lists the model as introduced in 1966, with a 4.3 cu. in. (70 cc) single-cylinder engine.
In layout and engineering, it was very much a working saw of its era: a direct-drive, one-man machine with rigid handlebars, manual chain oiling, and no chain brake. Its construction used sand-cast magnesium, while the cylinder was aluminum with a cast-iron sleeve, a combination aimed at keeping weight down while preserving durability.
Mono SL-245 for sale
The saw pictured throughout this article is listed on eBay with seller ‘paveman56’ in April 2026, who regularly has interesting chainsaws for sale. Whatever time you’re visiting this article, make sure you check out what’s for sale.
We love these pictures, which give us a great example of the Mono SL-245, even though this saw has been well-used and suffered some damage. It’s offered as a “parts or repair” chainsaw.
The full eBay description:
Vintage Mono SL245 Chainsaw w 15″ Hardnose Bar For Parts or Repair
Mono Line SL245, a 70cc saw made in the late 1960’s.
Has spark, compression feels very good, and it sounds good turning over.
What I can see of the piston/cyl through the exhaust looks good. Rear handle is welded in three spots, all welds are solid. Recoil has a cracked cover but works as it should. No chain. Manual oiler works. Both tanks need flushed but no rust is seen. Throttle lock is not holding. A few of the cylinder fins are broken/ smushed underneath as is the aluminum heat shield.
It came with two air filters, both have a big split. Chain tensioner screw is bent. Mono sticker is peeled and about to fall off. Bar measures about 15/5″ from the front, has good hardened tip left.
Selling As Is for parts or repair, no refunds or returns. I believe I’ve found everything wrong but I can’t guarantee it.
Please enlarge all photos for a close look, ask any questions.
Selling As Is, for parts or repair, so no returns or refunds.
It’s listed for US $80.
| Spec | Mono SL-245 |
|---|---|
| Manufacturer | Mono Manufacturing Co., Springfield, Missouri, U.S.A. |
| Year introduced | 1966 |
| Engine displacement | 4.3 cu. in. (70 cc) |
| Bore | 2.09 in. (53 mm) |
| Stroke | 1.25 in. (31.7 mm) |
| Cylinder type | Aluminum with cast-iron sleeve |
| Intake method | Reed valve |
| Drive type | Direct drive |
| Clutch | Fairbanks Morse centrifugal |
| Construction | Sand-cast magnesium |
| Ignition / magneto | Tecumseh |
| Oiler | Manual |
| Chain brake | None |
| Recommended fuel | Regular gasoline |
| Fuel-oil ratio | 10.6:1 |
| Supplied bar lengths | 16 in. to 20 in. |
| Other period chain/bar listings | Oregon guide lists SL-245 among Mono direct-drive saws with replacement setups up to 21 in. |
Acres also notes that the SL-245 used a Power Products AH-440 engine, type 1546, and Oregon’s late-1960s application guide groups it with the SL-145, SL-246, and later Model 48 in Mono’s direct-drive family. That is interesting because the SL-145 shares the SL-245’s same 70 cc displacement, 53 mm bore, 31.7 mm stroke, reed-valve induction, rigid handlebar layout, manual oiler, Tecumseh ignition, and sand-cast magnesium construction.
The SL-245’s squarish, almost industrial look makes sense for a saw built with sand-cast magnesium, a rigid handle system, direct drive, and a fairly straightforward engine-and-clutch package rather than a more isolated, comfort-focused layout.
In other words, it looks the way it is built: mechanical, flat-sided, and serviceable. That also helps explain what makes it feel a little different from some other late-1960s saws. The SL-245 kept an older-school formula with manual oiling, no chain brake, rigid bars/handles, and a very rich 10.6:1 fuel mix using SAE 30 non-detergent oil. This was at a moment when anti-vibration systems were already starting to appear elsewhere in the industry and chain-brake development was still ahead.
The tag on this saw states:
MONO MFG. CO.
Springfield, Missouri
MODEL: SL 245
TYPE: 1460
Here are the rest of the pics from ‘paveman56’.
