How to Replace a Honda Thermostat

How to Replace a Honda Thermostat

Here’s how to replace a thermostat on a 4 cylinder Honda 2.4L engine.

The thermostat is responsible for controlling the flow of the engine coolant as it circulates through the engine block. When the engine is cold, coolant does not flow. Once the engine warms up, the thermostat opens, circulating coolant to keep it at optimum operating temperature.

Sometimes the thermostat fails to open or close, causing the engine to run cold or overheat. The thermostat can also be replaced as a preventative measure when the engine coolant is drained, such as when changing a radiator or water pump.

Never work on the cooling system when the engine is hot. Drain the radiator through the bottom petcock valve and dispose of the coolant safely.

The thermostat is located on the engine block facing the front of the vehicle, under the intake plenum. There’s three 10mm bolts that need to be removed, along with the clip for the lower radiator hose.

Have a catch can located underneath the thermostat to catch remaining coolant in the block when the thermostat is removed. Replace the gasket and clean all mating surfaces with brake cleaner.

Replace the 10mm bolts and torque to 86 in-lbs using a torque wrench to avoid leaks. Replace the radiator hose.

Refill the cooling system with a 50/50 mixture of phosphate and silicate free Honda compatible engine coolant. Leave the radiator cap off and turn on the heater to cycle all the air through the system until the fans turn on and bubbles stop appearing.

This video was demonstrated on a 2004 Honda Accord 4 Cylinder. Procedure is the same for 2003-2012 Honda Accord and similar for the CR-V, Element, Civic, Acura RSX, and CSX.



Wigberto Gil Brito says:

My friend for the next explicación you must speak slowly….::

Tommy Coates says:

How long was this repair ?

P DR says:

Video is excellent & accurate but it will NOT B QUICK. Very tight area. Unless experienced it will take a while. As stated dang good vid

Deneteus says:

You made removing the lower radiator hose look too easy. My pipe won't come loose from the housing. I already got the thermostat housing changed faster than removing that part.

dest151 says:

Perfect and didn't miss a video by far.

Gary Bates says:

I wish all repair videos were like that. Absolutely great job Thanks!

Jack Mihof says:

Bruh thank you for just getting to it and not making dumb jokes. Fucking best car video I’ve ever seen and I’m serious as fuck. You’re a bad ass for this one

Isaac khan says:

Looks simple enough. Great video, thank you!

Michael Hanley says:

Great video! Thorough, and to the point!


My car 2009 .its 11 years old should i replace? Its not bad yet but just be safe .

Earl Spencer says:

Did this and heater still not working well. One of the vents seems to work the others blow cold air. Does it take a while to get going? What do you recommend?

Earl Spencer says:

Tried this. Not easy. Hose was stuck took forever to get off. Finally used a lot of muscle and it came off. Bolts were rusted had to wd40 them luckily they did not strip. There is extremely little clearance on the bottom bolt. Very difficult to screw back in. Keep a magnet handy. If you have a hard time getting bolts back in they are probably too rusted to fit through the thermostat housing. File the smooth part down.

dasboot360 says:

I have to replace my radiator soon? Should I do the thermostat as well ? What about a water pump ? My Honda CR-V has about 180k miles. Thanks

Earl Spencer says:

Does this fix P0128 code?

Anibal Puerto Rico says:

Great job question 2011 honda accord is the same?
Is it okay that i bought the thermostate at advanced auto parts

Viquh says:

This video was incredible. Thank you


Why rattling noise in honda accord euro cu2.

K G says:

Thanks for the great info! Please keep it up!

Carlos Alejandro Mercado Diaz says:

When thermostat is damaged, does ir show a code in the cluster?

christian cardona says:

Best video so far. 3 minutes and you covered all the important points it takes other guys 15+ minutes to do

Mike C says:

Is that a sock?

Andy Ortaaslan says:

Do you know if the ring gasket around the thermostat for the V6 is all that's required or must I place another gasket for the housing to the block.?

mario sarabia says:

Actually the thermostat is responsible for maintaining proper engine temperature wether hot or cold.

Tony says:

Is more difficult on a Acura Rsx? I've heard that you gotta remove the whole front bumper from some people

Vincent Rodriguez says:

My 2004 accord does not spin the radiator fan automatically.
The fans only spins when I turn on the AC.
What could be the problem?
Thank you speedkar.
Learning a lot from your videos.

Jacob Lazerus says:

Whats the estimated duration of a job like this? 15 min with moderate skills and tools?

Gabriel Sanchez says:

Great video on point easily explained

Lebron Jordan says:

Thanks for sharing, this will help me when my 3 Honda's needs thermostat replacement!

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