thermostat problem

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Hi HELP PLEASE. I've got quite a problem with my 2 litre petrol fourtrak at the moment the hoses to and from the radiator are completely different temperatures after driving the car for about 15 20 + miles the top hose was quite warm and the bottom one was stone cold i thought it might of been the thermostat sticking so i removed the housing only to find that there wasn't a thermostat fitted i went out and bought the one that is supposed to fit the engine but it seems far too big for the housing has anyone else ever had this problem with the thermostat if so how was it sorted also would the water temperaure cause the engine to run badly when accelerating hard.
thanks Tom

I had the same quandry. It t

I had the same quandry. It turns out some bright spark at Toyota (it's a toyota engine, in case you didn't know already) decided to put the thermostat in the return hose. Basicly where you think the thermostat should be is just a bolt on pipe fitting. The thermostat housing is where the bottom hose goes back into the engine on the right habd side.
The top hose will therefor get hot befor the thermostat opens due to conduction, as there is no barier stopping the hot water from circulating into the top of the rad. However the bottom hose stays cold as untill the thermostat opens the water in the rad can not return to the engine.

Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.

thermostat

Hi thanks very much for the reply I was begining tear my hair out wondering where the thermostat was. i've now changed it but the bottom hose is still staying cold whilst the top hose gets hot but it doesn't overheat the engine, asuming that the new thermostat is working propewrly do you have any ideas as to what else could cause the top hose to be hot and the bottom hose to be cold after its been run for quite a while, would this happen if the water pump was broken or would the engine simply overheat if the water pump was broken.
thankyou Tom

As I said the top hose will s

As I said the top hose will still get hot, as hot water will find it's way up there with no thermostat to stop it. However no cold water from the botom of the rad will go into the engine until the thermostat opens, due to the water going past it from the rad bypass pipe getting to hot. The bottom hose should never get more than warm, as the water in it has been cooled whilst traveling down the rad.
If the water pump was not working, the hoses would probably not get as hot, and the engine would over heat.

Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.