1995 odyssey thermostat

Does anyone know where thermostat is localted on Honday Odyssey 1995? Is it
difficult to change it?
Thanks,
Vadim.

 

Follow the big hose from the top of the radiator back to the engine. It
will be at the engine end of it. Its not harder to change than on most
other cars.

 

Follow the big hose from the top of the radiator back to the engine. It
will be at the engine end of it. Its not harder to change than on most
other cars.

 

You mean the hose from the BOTTOM of the rad, no? Most (all?) modern cars
have that setup.

 

You mean the hose from the BOTTOM of the rad, no? Most (all?) modern cars
have that setup.

 

(Oops - think I sent a blank response because my fingers are stupid.)

I don't understand why that is. In the days of yore they were attached to
the head, on the upper radiator hose, so the temperature of the head would
be regulated. Has something changed?

Mike

 

(Oops - think I sent a blank response because my fingers are stupid.)

I don't understand why that is. In the days of yore they were attached to
the head, on the upper radiator hose, so the temperature of the head would
be regulated. Has something changed?

Mike

 

You may be right. I sold the Odyssey to my daughter over 3 years ago, so
its been awhile since I've had my head in that engine. Both radiator hoses
connect on the top of the engine. The thermostat is in the one closer to
the firewall.

 

You may be right. I sold the Odyssey to my daughter over 3 years ago, so
its been awhile since I've had my head in that engine. Both radiator hoses
connect on the top of the engine. The thermostat is in the one closer to
the firewall.

 

Yes. Two things in particular:

1) It used to be that the thermostat opened to send hot water TO the rad
FROM the head.
That was when the thermostat was in the TOP hose.
Now, the thermostat opens to admit cooled water FROM the rad back TO the
head.
This is when the thermostat is in the BOTTOM hose.

2) Many rad caps no longer hold pressure until the fluid begins to boil.
You'll notice that your rad hoses may be squishy and not firm when the
engine is warm.

These two changes apparently mean greater cooling system efficiency,
necessary with modern reduced capacities.

 

Yes. Two things in particular:

1) It used to be that the thermostat opened to send hot water TO the rad
FROM the head.
That was when the thermostat was in the TOP hose.
Now, the thermostat opens to admit cooled water FROM the rad back TO the
head.
This is when the thermostat is in the BOTTOM hose.

2) Many rad caps no longer hold pressure until the fluid begins to boil.
You'll notice that your rad hoses may be squishy and not firm when the
engine is warm.

These two changes apparently mean greater cooling system efficiency,
necessary with modern reduced capacities.

 

1) makes sense when I think about it. 2) escapes my tired brain, but I'll
take your word.

How does the bottom-mounted thermostat sense the temperature? Does the pump
feed a loop that brings coolant from the head to the thermostat?

Mike

 

1) makes sense when I think about it. 2) escapes my tired brain, but I'll
take your word.

How does the bottom-mounted thermostat sense the temperature? Does the pump
feed a loop that brings coolant from the head to the thermostat?

Mike

 

"Michael Pardee" <> floridly penned in

You don't have to. Next time your car is full warm, go squeeze the rad
hoses. Sometimes they'll be firm, sometimes they'll be soft as though the
engine was cool.

The thermostat is still top-mounted, at the UPPER end of the bottom hose,
since it needs to be where the heat is (heat rises).


With the old system where it's in the top hose, the sequence is this:
1) Water in block and head heats up
2) Thermostat opens and hot water flows to the rad
3) Water cools in the rad and is then pushed back into the block by the
water pump from the lower hose
4) As the cool return water comes through the block back to the thermostat
again, the thermostat closes, limiting water flow until block heats up
again.

With the new system where it's mounted in the bottom hose:
1) Water in the block heats up, with the heat backing up to where the
thermostat is
2) Thermostat opens, allowing cool water from the lower rad hose to be sent
to the water pump and pushed back into the block
3) Cool rad water makes thermostat close up again and water flow stops
4) Sequence repeats from Step #1.

Apparently this second system is better suited to cooling systems with
limited capacity. The limited capacity seems to be a response to weight-
cutting in order to help comply with government CAFE rules.

 

"Michael Pardee" <> floridly penned in

You don't have to. Next time your car is full warm, go squeeze the rad
hoses. Sometimes they'll be firm, sometimes they'll be soft as though the
engine was cool.

The thermostat is still top-mounted, at the UPPER end of the bottom hose,
since it needs to be where the heat is (heat rises).


With the old system where it's in the top hose, the sequence is this:
1) Water in block and head heats up
2) Thermostat opens and hot water flows to the rad
3) Water cools in the rad and is then pushed back into the block by the
water pump from the lower hose
4) As the cool return water comes through the block back to the thermostat
again, the thermostat closes, limiting water flow until block heats up
again.

With the new system where it's mounted in the bottom hose:
1) Water in the block heats up, with the heat backing up to where the
thermostat is
2) Thermostat opens, allowing cool water from the lower rad hose to be sent
to the water pump and pushed back into the block
3) Cool rad water makes thermostat close up again and water flow stops
4) Sequence repeats from Step #1.

Apparently this second system is better suited to cooling systems with
limited capacity. The limited capacity seems to be a response to weight-
cutting in order to help comply with government CAFE rules.