90 yj running hot

Just got my jeep back from the shop after the water pump went. Now it is
running hot. Will go up to just below red line, then drop back down to
normal running temp. checked the fluid in the rad and it is up to the top,
but the overflow bottle was real low. topped that up and it is still
running hot. any ideas? radiator was pulled and checked when the water
pump was done. its a 6 cylinder. any ideas as to what may be up?
thanks.

Jason Halsey did pass the time by typing:
> Just got my jeep back from the shop after the water pump went. Now it is
> running hot. Will go up to just below red line, then drop back down to
> normal running temp. checked the fluid in the rad and it is up to the top,
> but the overflow bottle was real low. topped that up and it is still
> running hot. any ideas? radiator was pulled and checked when the water
> pump was done. its a 6 cylinder. any ideas as to what may be up?
> thanks.

Thermostat sticking or possibly the wrong pump. One turns clockwise,
the other counterclockwise.

You should be able to see the flow by looking into the radiator.
(just do it with the system cool)

--
DougW

As Doug said: wrong pump (they are different for the V belt and
serpentine versions) or stuck thermostat.

take it back to the shop and have them look at it.

DougW wrote:

> Jason Halsey did pass the time by typing:
>
>>Just got my jeep back from the shop after the water pump went. Now it is
>>running hot. Will go up to just below red line, then drop back down to
>>normal running temp. checked the fluid in the rad and it is up to the top,
>>but the overflow bottle was real low. topped that up and it is still
>>running hot. any ideas? radiator was pulled and checked when the water
>>pump was done. its a 6 cylinder. any ideas as to what may be up?
>>thanks.
>
>
> Thermostat sticking or possibly the wrong pump. One turns clockwise,
> the other counterclockwise.
>
> You should be able to see the flow by looking into the radiator.
> (just do it with the system cool)
>

but would either of those account for the temperature fluctuations? ie
running up to the red, then dropping, then back up to red and dropping, etc?

"RoyJ" > wrote in message
ink.net...
> As Doug said: wrong pump (they are different for the V belt and serpentine
> versions) or stuck thermostat.
>
> take it back to the shop and have them look at it.
>

The variation is usually a bad thermostat.

Jason Halsey wrote:
> but would either of those account for the temperature fluctuations? ie
> running up to the red, then dropping, then back up to red and dropping, etc?
>
> "RoyJ" > wrote in message
> ink.net...
>
>>As Doug said: wrong pump (they are different for the V belt and serpentine
>>versions) or stuck thermostat.
>>
>>take it back to the shop and have them look at it.
>>
>
>
>

RoyJ wrote:

> The variation is usually a bad thermostat

Could air trapped in the block or hoses cause this? Just a thought...

scotty