well i have a problem with my cooling system. When i start the car it runs ok. I am going to do the bubble test (starting car when cold while the themostat cap is off) to see if any bubble form - meaning i have a bad water seal. I heard from a rotary expert that if i dont see bubbles/overflowing coolant out of the thermostat neck within a minute it isnt the water seal thats causing me the problems but something else. Could replacing all the coolant hoses with brand new ones help/fix the problem. To ask, could a bad coolant hose somewhere cause my coolant to seem to be boiling (note: temperature guage shows normal temp.) and overflowing out of the overflow hole on the resevior?

 

that normaly is a bad coolant seal.... are you burning any coolent? white smoke? do the bubble test first. could also be a defective pressure cap.

 

a bad radiator cap could cause that also?

 

and if u mean white smoke from the exhaust, only alittle on startup but i hear thats normal for rotarys

 

I had the same problem and it turned out to be a bad pressure cap. Peace!

 

if your pressure cap isnt holding pressure the boiling point for the coolant gets lower. and if its boiling it can boil out of your reservoir or the cap itself.

 

pressure cap being the radiator cap? or the ast cap? or both?

 

replace both.

 

P.S dont drive your car untill you fix it. thats asking for O rings to be destroyed.

 

can the radiator caps to be bought off rx7store.net be used fo either the ast or themostat? the 1.3 bar greddy one is the one im considering buying 2 of.

 

what kind of ast do you have? 1.3 bar is to high

 

im using the stock one.

 

just go with the stock ast cap. actually... now is a good time to upgrade to a aftermarket AST.

 

i had the same symptoms and it went way when i replaced the radiator cap.

 

bubble test would probably only work if u have really bad o-rings. best way to look at it is if u burn white smoke on start up after letting your car sit overnight or somethingif ur not seeing fluid or anything on the ground after letting it sit over night, thats kinda the only other way that your getting air in your system.

 

bubble test would probably only work if u have really bad o-rings. best way to look at it is if u burn white smoke on start up after letting your car sit overnight or somethingif ur not seeing fluid or anything on the ground after letting it sit over night, then i dont really think u have a leak in your hoses/pipes. But it doesnt hurt to check, my upper radiator hose just blew and i also have a ripped water pump belt. NON-ROTARY mechanics are telling me its cause my waterpump belt ripped causing my fluid to overheat. But they dont know that the bubbling has been happening way before this incident.

 

can i use the greddy 1.3 bar cap to replace my thermostat cap?

 

yes.

 

I'd stick with the oem thermostat cap.

 

why is that? oem over the greddy 1.3 i mean? cause i alrdy ordered the greddy....

 

i bought a HKS 1.3 when i was at D1 its been on my car for like a year i think and autometer gauge temp always looks good.

 

AZN. it will work fine. dont worry. mine has been on my car for over 6 months.. and no probs. temps are perrrrrfect.

 

ok thanks alot u guys for ur input n advice lets see if it works n hope it isnt a seal.