Gaskets, Seals & O-Rings
About Gaskets, Seals & O-Rings
Gaskets, seals and O-rings keep oil, coolant, compression and exhaust gas where they belong. A seal that has hardened, been crushed or torn lets fluid weep out or air leak in, and it is usually replaced any time the part it seals is taken apart. Riders shop here for a gasket kit for an engine rebuild or top-end job, or for a single seal that has started to leak.
Start with the job. A top end gasket kit covers the cylinder and head area, and a complete gasket kit covers the whole engine, usually listed either with or without oil seals, so read the title to see which one you are getting. Smaller listings cover the cooling system, such as a water pump seal and coolant tube O-ring sets, and others cover the exhaust or crankshaft bearing and seal sets. Each is made for a particular engine and years, with kits for Polaris, Yamaha, Harley-Davidson, Gas Gas, Husqvarna and KTM machines. Use a gasket with clean, flat mating surfaces, and follow the manual for sealant and tightening.
Brands in this category include Athena, Vertex, ProX, Cometic and Moose Offroad. For a cooling-system repair, see Water Pumps and Pipes & Hoses. The wider group is Engine Cooling. Pick your machine in the Ride Finder at the top of the page to see the kits listed for your model.
FAQs on engine gaskets and seals
What is the difference between a top end and a complete gasket kit?
A top end kit includes the gaskets for the cylinder, head and related parts, so it suits a piston or cylinder job. A complete kit covers the whole engine, including the crankcase and covers, and is for a full rebuild. Read the listing to see exactly what each includes.
Should I choose a kit with or without oil seals?
Choose with seals if you plan to replace the engine's oil seals during the job, which is sensible when the engine is open and the seals are old. Choose without if you already have them or they are not due. The title usually states which kind it is.
Can I reuse an old gasket?
It is better not to. Gaskets compress and harden once they are installed, and a used one often does not seal again. Replace it when you open the joint, clean both surfaces and follow the engine manual's instructions for any sealant.
Do I need gasket sealant?
It depends on the joint. Many gaskets are designed to seal without sealant, and some joints call for a thin film of it. Follow the service manual for each joint, because too much sealant can block oil passages.
How do I find the right gasket kit for my bike?
Match the make, model and years in the listing to your engine. Pick your machine in the Ride Finder at the top of the page to narrow the list. Kits are made for one engine, so check the engine size or model where the listing gives it.
