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.

[cardonaman]

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

[Jorisinflorida]

I love this, the guy gets right to it, no fluff, no dragging ass, get's the procedure done in record time.

[OmegaReds]

All repair videos should be like this good job bro!

[maxjet]

This is by far, the BEST DIY video I have seen in a long time, for being DIRECT TO THE POINT. Thanks, job well done. Q. on that same engine, where is the ETC sensor? I cannot locate a good photo for it.
Thanks.

[dvmartel]

One of the best how-to vids I've ever seen, perfect and to the point. Thank you!

[carlosberdeal]

After watching several other videos... This is the BEST!!! Thank you for not messing around and getting the job done step by step and not missing a beat. GREAT JOB! Subbed!

[uwsbvrv]

SpeedKar99, your videos are nicely produced and informative. You have a real knack at getting the point across and explaining the processes.

[ekrekel]

This may be the best informational video I've ever seen, very succinct, to the point. Thanks!

[garybates]

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

[joelatwar]

This is a great, no BS, straight to the point repair video. Thanks

[AbdullahAwamleh]

I love how efficient your videos are. You save us all a ton of time. Thank you!

[azmyin]

Best video ever. Straight to the point. Clear and concise step by step video

[martini]

Thank you for “trimming the fluff” straight to the point.

[lebronjordan]

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

[rickp.]

It's amazing video presentation working while explaining unlike the other video on you tube a lot of talking and then keeps working and not explaining

[Carlos-lnlx]

Excellent video, trying to find a vid for my 08 crv, slightly different layout but super similar thermostat. Some guys made videos for my exact car and didn't help me understand nearly as much as this. Didn't fully think of how the thing works but I'm just gonna trace my radiator hose back and find rhe thermostat myself n not bother with other videos lol. Well done fr

[annettehaymon]

I am a woman, and I rate this as being the Best Video and clear to every detail.

[futureddshanley]

Great video! Thorough, and to the point!

[peaman]

Excellent, no nonsense, video.
Well done!!!

[mdhaskins]

Fantastic video- Straight and to the point!