Oil Change Gasket Kit | Honda CB175 / CL175 / SL175
Every CB175 family oil change needs a fresh drain plug O-ring at minimum. If you're cleaning the centrifugal oil filter and the oil rotor — recommended every other oil change — you'll also need fresh O-rings and gaskets for the right side cover and the filter chamber. This kit bundles all 8 gasket types you need for an oil change with filter clean on any CB175 / CL175 Scrambler / SL175 from 1969 through 1973, plus the closely-related CD175 and CA175.
Why You Need This
Honda specs the CB175 family oil change at every 1,500 miles. The factory schedule calls for cleaning the centrifugal filter and oil rotor every other oil change (every 3,000 miles) to keep sludge from packing into the rotor and choking off oil delivery. The CB175 oil system is doubly filtered — the centrifugal filter on the pump outlet and a mesh screen filter on the pump inlet — and skipping the cleanout starves the top end of oil over time.
The moment you pull the right side cover off, you've broken the rotor cover and crankcase cover gaskets. They don't go back together cleanly without fresh ones. In the past, you either reused old gaskets — which leak — or bought a full overhaul kit and paid for parts you didn't need. This kit gives you exactly the 8 gasket types required for an oil change with filter clean. Nothing extra.
One thing that makes the CB175 family different from the bigger twins (CB350 / CB360 / CB450) is the filter cover design. The 175 uses a single center screw to retain the oil filter cover instead of the snap ring used on the bigger bikes. CB175 also has an access panel on the right side cover for routine filter access — the CB200 doesn't, which is why the two kits are not interchangeable.
Specifications
| Spec | Detail |
|---|
| Replaces OEM Part Numbers | 91301-216-000, 91305-426-003, 91305-216-000, 91310-MG7-003, 91305-634-961, 91309-700-000, 91309-302-000, 91304-HB3-003, 91302-200-000, 91302-943-003, 15219-302-000, 11691-354-306, 11691-216-000, 11691-354-000, 11394-302-306, 11394-302-010 |
| Fits Models | CB175 K3-K7 (1969-1973), CL175 K3-K7 (1969-1973) Scrambler, SL175 K0-K1 (1970-1972), CD175, CA175 — DOES NOT fit 1968 CL175 K1 sloper engine (CB160 platform) |
| Sold As | Kit (10 pieces, 8 gasket types) |
Important: Use 100% mineral 10W-40 only. Most modern diesel oils — Shell Rotella T4, Chevron Delo 400, Mobil Delvac 1300 — reformulated to semi-synthetic in late 2023. Semi-synthetic causes clutch slip on these wet-clutch engines. 15W-40 mineral diesel oil is fine as an alternative if you can verify it's still 100% mineral.
Gasket grease trick: Apply a thin layer of grease to both faces of each new gasket during install. Next time you pull the cover, the gasket releases cleanly and you may be able to reuse it.
CB175-specific filter cover note: The oil filter cover access screw should be a button-head Allen (M6 × 20), not a socket-head. The socket-head's larger top mass restricts oil flow through the passageway hole behind it.
What's in the Kit
- A: Stator Rotor Cover Bolt O-Rings — 3 pieces
- B: Oil Rotor Cover O-Ring — 1 piece
- C: Oil Filter Cover O-Ring (Small) — 1 piece
- D: Oil Filter Cover O-Ring (Large) — 1 piece
- E: Oil Drain Plug O-Ring — 1 piece
- F: Oil Pump Gasket — 1 piece
- G: Stator Rotor Cover Gasket — 1 piece
- H: Right Crankcase Cover Gasket — 1 piece
Total: 10 pieces, 8 unique gasket types.
Honda CB175 / CL175 / SL175 Gasket Kits| Kit | Letter | Gasket | Qty |
|---|
#4176
Oil Change Gasket Kit
(Includes Gaskets A-H) | A | Stator Rotor Cover Bolt O-Rings | 3 |
|---|
| B | Oil Rotor Cover O-Ring | 1 |
| C | Oil Filter Cover O-Ring (Small) | 1 |
| D | Oil Filter Cover O-Ring (Large) | 1 |
| E | Oil Drain Plug O-Ring | 1 |
| F | Oil Pump Gasket | 1 |
| G | Stator Rotor Cover Gasket | 1 |
| H | Right Crankcase Cover Gasket | 1 |
#4177
Service Gasket Kit
(Includes Gaskets A-M) | I | Points Cover Gasket | 1 |
|---|
| J | Intake Manifold O-Rings | 2 |
| K | Intake Manifold Gaskets | 2 |
| L | Left Crankcase Cover Gasket | 1 |
| M | Top Cam Cover Gasket | 1 |
#4175
Overhaul Gasket Kit
(Includes Gaskets A-Y) | N | Cylinder Base Gasket | 1 |
|---|
| O | Head Gasket | 1 |
| P | Exhaust Gaskets (copper) | 2 |
| Q | Camshaft End Cover | 2 |
| R | Dipstick O-Ring | 1 |
| S | Clutch Lifter Adjuster O-Ring | 1 |
| T | Valve Cover O-Ring | 4 |
| U | Exhaust Guide to Head O-Rings | 2 |
| V | Tensioner Bolt O-Ring | 1 |
| W | Cylinder Head Dowel Oil Passage O-Ring | 2 |
| X | Exhaust Valve Stem Seal Upper | 2 |
| Y | Exhaust Valve Stem Seal Lower | 2 |
Installation
Difficulty: Beginner-Intermediate — routine oil change is straightforward; full filter clean adds the right side cover removal step.
Tools needed: wrench/socket for drain plug, JIS or Allen driver for cover bolts, oil drain pan, lint-free rag, razor blade or gasket scraper, M8 × 1.25 pitch bolt (for rotor cover puller, if doing the filter clean), fresh 10W-40 mineral oil (about 1.6 qt), zinc ZDDP additive (2 oz).
- Warm the engine, place on center stand. Have a drain pan ready.
- Break the drain plug loose with a breaker bar — turn the right direction or you'll strip the threads. Drain the oil.
- Kick the engine over a few times to clear the last of the oil.
- Inspect the drain plug for thread or hex damage. Replace if rounded off.
- Quick path (oil change only): Pop the access panel on the right side cover — CB175 has this; CB200 doesn't. Replace the drain plug O-ring (Letter E). Move to step 14.
- Full path (oil change with filter clean): Loosen the right side cover bolts in a star pattern. If they're original JIS Phillips, an impact driver helps break them loose — consider switching to Allen bolts on reassembly. Tap the cover lightly with a rubber mallet to break the gasket seal. (If you greased the gasket on a prior service, it may release cleanly.)
- Remove the single center screw holding the oil filter cover. The cover comes off.
- To pop the rotor cover for cleaning, thread an M8 × 1.25 pitch bolt into the center hole until it bottoms on the crankshaft and pushes the cover off.
- Clean the centrifugal rotor with compressed air. Wipe sludge from the chamber with a lint-free cloth.
- Scrape any remaining gasket material from the case and cover sealing surfaces with a razor blade or gasket scraper. Don't gouge the aluminum.
- Apply a thin coat of grease to both faces of each new gasket — Letter B (rotor cover O-ring), Letter G (rotor cover gasket), Letter H (right crankcase cover gasket). The grease helps with clean release on the next service.
- Reinstall: rotor cover with new B + G gaskets. Oil filter cover with new C + D O-rings, retained by a button-head Allen (M6 × 20) — not a socket-head bolt. The socket-head's larger top mass restricts oil flow through the passageway behind it.
- Apply anti-seize to the right side cover bolt threads. Reinstall the cover with new H gasket. Cross-pattern tighten from middle outward. Torque the 8mm bolts to 2.3-2.8 kg-m (16.6-20.2 ft-lbs).
- Replace the dipstick O-ring (none in this kit — in the Overhaul kit if needed) and the drain plug O-ring (Letter E). Reinstall the drain plug — snug, do not over-tighten.
- Refill with 1.5 L (1.6 US qt) SAE 10W-40 mineral oil. Add 2 oz zinc ZDDP additive.
- Run the engine briefly. Check for leaks at the cover, filter cover, and drain plug. Re-check oil level on the dipstick — dip it, don't thread it in.
If you're going deeper to clean the mesh pickup screen on the pump inlet: That requires removing the clutch basket and the oil pump itself. The Service Kit (#4177) covers the gaskets you'll need for that level of access.
Our walkthrough video covers the full filter clean procedure on the CB175 family — right side cover removal, the M8 puller bolt trick, the button-head Allen note for the filter cover access screw, anti-seize on reassembly, and the kickstart shaft seal opportunity while you're in there. We also have a separate basic oil change video covering CB175 / CL175 / SL175 / CB200 / CL200 if you don't need the full filter service.
Frequently Asked Questions
Will this kit fit my CD175 or CA175?
Yes. The CD175 and CA175 share the same engine architecture as the CB175 family — same gaskets, same OEM part numbers. Confirmed by our service team across multiple customer orders.
Will this kit fit my 1968 CL175 K1 sloper engine?
No. The 1968 CL175 K1 used a "sloper" engine based on the earlier CB160 platform — entirely different gasket sizes and layouts. The fitment chart starts at K3 (1969) for both CB175 and CL175 because that's when Honda switched to the upright engine these gaskets fit.
Do I need this entire kit at every oil change, or only when cleaning the filter?
Only Letter E (drain plug O-ring) is strictly required at every oil change. Letters A, B, C, D, F, G, and H come into play when you pull the right side cover for the centrifugal filter clean — recommended every other oil change (every 3,000 miles). The kit is priced for one cleaning service.
What's the difference between the Oil Change, Service, and Overhaul kits?
The Oil Change Kit (#4176, this product) covers gaskets A-H — exactly what you need for a routine oil change with centrifugal filter clean. The Service Kit (#4177) covers gaskets A-M — adds the points cover, intake manifold gaskets and O-rings, left crankcase cover, and top cam cover for full tune-up service or cylinder head work. The Overhaul Kit (#4175) covers A-Y — every gasket on the engine including the head, cylinder base, exhaust, valve seals, and dipstick O-ring for a complete engine teardown.
Are the CB175 and CB200 oil change kits interchangeable?
No. The kits look similar at a glance, but the CB175 family and CB200 family use different gasket sizes and slightly different right-side-cover designs. The CB175 has an access panel on the right side cover for routine filter access; the CB200 does not, which means a CB200 service is a different procedure even though the gasket types overlap. Use this kit (#4176) for CB175 / CL175 / SL175 / CD175 / CA175 only. Use the #4179 CB200 / CL200 Oil Change Kit for the CB200 family.
What oil should I use?
SAE 10W-40, 100% mineral oil. 15W-40 mineral diesel truck oil works as an alternative. Avoid full synthetic and semi-synthetic — both cause clutch slip on these wet-clutch engines. Most modern diesel oils (Shell Rotella T4, Chevron Delo 400, Mobil Delvac 1300) reformulated to semi-synthetic in late 2023, so check the bottle. Add 2 oz of zinc ZDDP additive per quart for cam and rocker protection.
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Last updated: May 2026
