ok heres the deal iv got a 91 hatch Si with a single cam ZC thats been over heating alot lately so i got a new radiator, hose's and thermostat...well it doesnt over heat anymore but now it will start to get really warm but when i rev to about 4000... it goes right back down so do i need a waterpump or what? cuz thats the only thing left oh and yeah the fan switch does work so i know its not that...any help would be great......

 

usually when the waterpump goes you will have the pinhole leaking? do you have any leaks?

 

come to thin about it now yeah i do....so is that why when i rev the temp goes back down then?

 

Well where is the leak around ?

It sounds like you could have a clogged system, whens the last time you did a flush ?

 

i cant really see where its coming from somewhere arould the bottom of the block, but yeah i flushed it last week and i work at goodyear so i used all the hightech bullshit machines to do it.

 

Take the timing cover off and inspect there, also it could be a stuck thermostat.

 

he said he has a new thermostat..... that shouldnt be stuck

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by uberhaulin &raquo;</TD></TR><TR><TD CLASS="quote">he said he has a new thermostat..... that shouldnt be stuck</TD></TR></TABLE>

I have seen brand new ones get stuck, and I also have seen people install them backwards.

 

lol i work at goodyear so no i didnt install it backwards but yeah iv seen that happen also.

 

Have you pressure tested it?
If it has a leak that is an easy way to find it..

How about the raditor cap? It has to hold pressure also..

 

It's getting warm because your coolant flow has been reduced either by a clog or the pump is cavitating.
All I know is if your water pump locks, it will take your timing belt with it. THen you get to buy a new head.