Honda Prelude Thermostat Replacement

Hi All DIYers...
Luckily the thermostat is suspected stucked closed.
That leads to this DIY creation to help others.

When the temperature is over half of the gauge, the fan will not turned ON.
To test the fan and switch, you can refer to the past DIY 

The lower hose or lower radiator cover is COLD enough to touch while the upper hose is HOT.
The temperature keep rising and you can hear weird hot water sound.

This is where the thermostat LIVE.
Need to loose only 2 BOLT sized 10. Easy enough.

Gently pull thermostat out by using flat screwdriver.

Never use tap water. The corrosion is minimal.

To confirm the thermostat is faulty, boil it in a water.
In this photo, it will never open.

19301-P08-316 Honda Thermostat.
Comparable with local one.

On the left is new Honda genuine thermostat.
While on the right is local one.
The local looks similar with genuine except the middle rubber valve.
FYI the local failed after 2 years or 30000.
Maybe the different material.

Softer springs.

A bit harder springs for local.

Test/boil it out before put it back into thermostat housing.

Open when Hot!

Close when Cold!

Clean the housing before put it back.
Follow marking on top or it will not fit.

Put some thin silicone gasket (optional but recommended).

Tighten the bolts.

Wipe off the excessive silicone gasket.

Reference. Click for bigger view.

Good Luck!


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