dhonda00

I have a honda accord 98 4 cylinders. the radiator fan won't come on after 30 mins engine idle. I've changed coolant sensor , coolant sending unit , coolant fan switch. I changed coolant already. I did bleeded air out of cooling system. I unplug the coolant fan switch and juse the wire to jumper across 2 terminal and the fan working perfectly. I plug it back but still. When i turn on the A/c the fan is run fine. when i let the eingine idle the temp gauge reachs almost to the Hot .

Anyone help me please !!

holmesnmanny

describe exactly where on the engine you replaced sensors


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dhonda00

i replaced thermostate and coolant fan swith at T-stat housing . and i changed water temp sensor and coolant seding unit under the distributor. and my radiator has been leaked so i changed it too.

bairdandrew77

Did you bleed the coolant properly? Or check/replace the thermostat?

holmesnmanny

When you replaced the thermostat did you make sure the jiggle valve is facing up ? If not it could have an air pocket there. I usually just cut the jiggle valve off on my thermostats.

bairdandrew77

Oops, didn't notice the part where you said you did change the thermostat.
What's the point in the jiggle valve? Just to let coolant seep past or something?

holmesnmanny

It's purpose is to allow air to pass through when you fill up the coolant so that an air pocket doesn't develop where the thermostat and fan switch are, which causes the thermostat not to open and the fan not to come on which causes the car to overheat.

Obviously air will be at the top and will pass through the jiggle valve as you add coolant to the system.

dhonda00

i bought thermostat from honda dealer and i replaced it . and how long does it take to bleed the air out of cooling system. I openned the bleed valve at T-stat housing and poured the coolant into the radiator until the i saw the water comming out from the bleed valve, i closed the bleed valve. i filled the coolant into the radiator until it's full. but the fan wont come one after i let the engine idle for 30 mins the the temp gague reached almost to the H

dhonda00

yes it faced up. the other day when i changed thermostat and i let the engine idle for 15 mins and i heard the fan running. since i 've been changed the coolant sensor and and coolant sending unit , my radiator fan won't come on anymore.

dhonda00

i'm gonna take out thermostat and check everything ok and put it back. so hopefully the fans are gonna work. Any advises for this procedures ?

holmesnmanny

Take out the thermostat and make sure the jiggle valve is facing straight up. Or better yet, just cut the thing off. It's not really necessary to have the jiggle valve itself. It is small enough of an opening not to affect anything and the thermostat will be able to do its job.

If you didn't get a honda fan switch now would be a good time. I'm gonna assume it's a honda fan switch.

To properly bleed do this...jack the front of the car all the way up..turn the temperature **** inside the car to full red. Loosen the bleeder valve. Fill the radiator with coolant until it comes out in a steady stream at the bleeder bolt then close the bleeder bolt. Fill up the radiator til it tops off, close the cap. Start the car and let it idle. Wait for the temperature to get to normal, then check the lower hose. It should be getting warm then hot. If it doesn't, before it gets above halfway turn the car off and report back. This would be the a problem with the thermostat. If it does get hot, check for the fans to come on before it gets above halfway. If they don't come on report back.

Do you have two fans ? meaning do you have ac ?

It should be safe to assume you replaced part number 15 with a honda part

http://www.hondapartscheap.com/parts...er-pump-sensor

dhonda00

last night i took out thermostat and i adjusted it faced up . i forgot to cut jiggle valve. the coolant fan switch was brand new. i dont think the water pump is problem because when i openned the cap i felt the water pressure and bubbling sound in reservoir tank. Now i'm going to try bleed air out. and will see.

Thanks for reply back

dhonda00

the coolant fan switch is not OEM i think the old fan switch is working and for some reason i did changeed it . so i think i may install it back to the T stat housing. is there any way to test the coolant fan switch working or not ?

holmesnmanny

There should be continuity across the pins when the temperature is around 195 or so. If the old one is still good you can give it another try.

However, there should be no bubble sound in the reservoir tank. If you did indeed hear bubble sound then you need to do a compression test on the motor to see if the head gasket is bad. You should never ever let the temperature gauge get above 2/3. If it does you're probably allowing your head gasket to get bad. It doesn't take long at that temperature to ruin a head.