Honda K Series Thermostat Case Seal 19322-PNA-00

Honda K Series Thermostat Case Seal - 19322-PNA-003

Doing a thermostat job on your K series and you need the rear thermostat case seal? Part number 19322-PNA-003. This is the OEM gasket that seals the back side of your thermostat housing, the piece that bolts to the engine block. It's not the gasket for the thermostat itself. This seal goes between the rear thermostat case and the block. When this gasket's old or damaged, you're getting coolant leaking from the back of your thermostat housing where it meets the block.

Here's Where This Gasket Goes

K series thermostats have two parts: the front housing where the thermostat sits, and the rear case that bolts to the block. This gasket seals the rear case to the block. It's the back seal, not the front one. When you're replacing your thermostat, you're pulling the front housing off to access the thermostat. But if you're doing a full thermostat assembly replacement or you're pulling the whole thing off the block for engine work, you're dealing with this rear gasket. Most people doing a quick thermostat swap don't touch this seal. But if you're pulling the rear case off the block or your rear seal's leaking, you need this gasket.

Replace It If You're Pulling the Rear Case

If you're removing the rear thermostat case from the block - for engine work, water pump replacement, or full thermostat assembly replacement - replace this seal. Don't reuse an old gasket that's been compressed against the block for years. It won't seal right when you put it back on. The gasket's cheap. Fresh seal means you're not chasing coolant leaks after you button everything up. If your rear thermostat case is leaking right now and you're just doing the thermostat, you might not need to pull the rear case. But if coolant's weeping from where the rear case meets the block, this seal's your problem.

Don't Confuse It With the Front Thermostat Seal

There are two seals in the K series thermostat assembly. This one (19322-PNA-003) is the rear case seal that goes between the rear housing and the block. The other seal goes between the front housing and the rear case where the actual thermostat sits. They're different parts. Make sure you're ordering the right seal for your job. If you're just doing a thermostat replacement and you're not pulling the rear case off the block, you need the front seal, not this one. If you're pulling the whole assembly off or you're leaking from the back, this is the seal you need.

What You Get

• Honda OEM thermostat case seal (part number 19322-PNA-003)
• Seals rear thermostat case to engine block
• Prevents coolant leaks at block interface
• Paper/composite gasket material
• Same seal your engine came with from the factory

Fits Your Car

• 2013-2015 Acura ILX
• 2002-2006 Acura RSX
• 2004-2014 Acura TSX
• 2003-2012 Honda Accord
• 2002-2015 Honda Civic Si
• 2002-2014 Honda CR-V
• 2012-2015 Honda Crosstour
• 2003-2011 Honda Element

Compatible Engines

• K20A2, K20A3
• K20Z1, K20Z3
• K24A1, K24A2, K24A4, K24A8
• K24Z1, K24Z2, K24Z3, K24Z7

Note: This seal goes between the rear thermostat case and the engine block. It's not the seal between the front housing and the rear case where the thermostat sits. If you're doing a quick thermostat replacement and you're not removing the rear case from the block, you probably don't need this seal. If you're pulling the entire thermostat assembly off the block, doing a water pump job, or you're leaking from the rear case-to-block interface, replace this seal. When you're installing it, clean both mating surfaces completely. Remove all old gasket material from the block and the rear case. Any leftover gasket material or dirt will cause leaks. The seal should sit flat on the block with no wrinkles or folds. Don't use RTV or sealant with this gasket, it's designed to seal on its own. Bolt the rear case down evenly. Torque the bolts to spec in the proper sequence (check your service manual). Don't overtighten or you'll crush the gasket and cause leaks. If you're doing a thermostat job and you're not sure which seal you need, check where your coolant's leaking from. Leaking from the front of the thermostat assembly? That's the front seal. Leaking from the back where the assembly meets the block? That's this seal.