Water pump and thermostat questions

rx4ur7 · 08-12-2009, 11:35 AM

Yes, replace it. Make sure that is for a rotary and matches the one you take out. Clean the surfaces carefully. Do not use power tools. The safest is to use a chemical gasket remover and a plastic scrapper. But if you are carefull you can do it by hand with new razors. But if you have not done a few cleanings on aluminum I recommend chemical.
Make sure all the surfaces are clean. I do not recommend using any RTV or sealant - see my forum on gaskets and RTV. If your surfaces are properly clean the gasket itself will work. Excess RTV that breaks off internally from either replacement has caused many overheating issues and engine failure due to it. I have had to do too many motors because of it.

Not trying to scare you, just save you some grief.

If you think you really have to use any gasket sealant, use a very, very thin film and try to keep it away from the inner surface.

On the FC you do have to be carefull about the main W/P Thermo housing to motor gasket leaking if you do not remove the whole assembly.

If you use an aftermarket pump, make sure of clearance for the impeller. Do not go rebuilt if you can. If you do not go to Ray at Malloy Mazda which I recommend, try autoparts warehouse they sell the NPW brand. Stant does make the proper thermostat.

Do not try to go cheap on these two items. It is a pay me now or pay me alot more later area.

Thread Tools
Show Printable Version Email this Page
Display Modes
Switch to Linear Mode Switch to Hybrid Mode Threaded Mode

08-12-2009, 11:35 AM	#5
rx4ur7 Rotary since 1972 Join Date: Nov 2008 Location: Tucson Posts: 231 Rep Power: 17	Yes, replace it. Make sure that is for a rotary and matches the one you take out. Clean the surfaces carefully. Do not use power tools. The safest is to use a chemical gasket remover and a plastic scrapper. But if you are carefull you can do it by hand with new razors. But if you have not done a few cleanings on aluminum I recommend chemical. Make sure all the surfaces are clean. I do not recommend using any RTV or sealant - see my forum on gaskets and RTV. If your surfaces are properly clean the gasket itself will work. Excess RTV that breaks off internally from either replacement has caused many overheating issues and engine failure due to it. I have had to do too many motors because of it. Not trying to scare you, just save you some grief. If you think you really have to use any gasket sealant, use a very, very thin film and try to keep it away from the inner surface. On the FC you do have to be carefull about the main W/P Thermo housing to motor gasket leaking if you do not remove the whole assembly. If you use an aftermarket pump, make sure of clearance for the impeller. Do not go rebuilt if you can. If you do not go to Ray at Malloy Mazda which I recommend, try autoparts warehouse they sell the NPW brand. Stant does make the proper thermostat. Do not try to go cheap on these two items. It is a pay me now or pay me alot more later area.