duehuynh

Do you have an 87-88 RX7?? If you do, please give your input in this matter.

I am looking to buy and replace my 2 radiator caps on my 87 Rx7 T2. Sounds like a simple job, but it is becoming a nightmare.

Looking at my car, there are two radiator caps. One cap sits right on top and at the center of the radiator. It is a round cap (no little wing thing) with japanese inscriptions and the description "Nichira 0.9" on it. Seems like Nichira also made the radiator. Immediately under this cap exits the overflow tube which goes to the overflow tank. The second cap, which is round and have left/right finger wings, is ontop of the engine and it covers the thermostat neck. It also have the "0.9" description written on it. Under this cap you also see another overflow tube, but it is not used. Both caps do not look the same from the exterior, and the interior mechanism does not look the same either, although both are the "pressure" type of cap.

If you go to Mazdatrix:

http://www.mazdatrix.com/b8.htm

my radiator cap over the thermostat neck looks like picture "g." The second cap over the radiator does not look like either "g" or "h." More over, read what Mazdatrix noted:

"For 86-88 please let us know your filler neck/cap system. Early 86's had the fill pressure cap and over flow tube at the thermostat cover, with a bleed valve at the radiator. Later ones have a flat cap, and no overflow tube at the thermostat cover, with the pressure cap and overflow on the top of the radiator. To further confuse matters, MAZDA created an "update" kit that moved the pressure cap to a remote location on the left side, with level sensor that has a tube coming out of it."

My guess is that I have a mix between the original and "upgraded" version. I have a overflow tube at the thermostat cover, but it is not used or connected to anything. It sounds like you are supposed to have 2 caps - one "pressure" cap for the overflow, and one "flat cap" For whatever reason, I have 2 "pressure" caps with 2 overflow tubes. However, only one is used.

If you have an 86-87, could you please look and tell us what you have???

Thanks a million..

dewey

mazdaspeed7

.9 is the pressure rating in Bar. 1 bar = 14.7 PSI, so .9 Bar is 13 PSI. I think they both should be the same, but having a S5, I dont know for sure.

Six Rotors

iTrader: (17)

Yes well I used to have the "flat" cap(ie without pressure relief) at the thermostat housing,and a pressure relief type at the radiator.Now I run with the pressure relief type in both spots because it was cheaper.It is not a problem running with a pressure relief type even when you don't need it,because it still gives you a seal on the top flange.
The plastic fitting on top of the thermostat housing has a a BLANK overflow pipe on both my 88s.

Keith

87 TII here. I have no overflow on the thermostat housing. I also have the "relocated pressure cap on the overflow tank" setup. I have pressure caps in both locations. Both had the same ratings. However, it occured to me that if the cap on the thermostat housing was venting a little lower in pressure then the other cap, I would be losing coolant. I was, so I took off the cap on the thermostat housing and did a fine calibration on it (bent the poopey out of the tabs so it would seal way tighter than .9 bar, essentially converting it into a "flat cap". Haven't lost any coolant since.

Irv, Keith's dad

VashtheStampede

great googely moogely... i have been leaking coolant onto my TID from the same stinkin thing. never realised why. i thought something was wrong with my cap flange fitting. thanks for the info =-)