any real tech heads...coolant flow?
 

guys, ive looked at the FSMs and cant work it out. Can anyone describe to me how the coolant flows through an RX7 engine? i.e filler neck, into rad, out of rad into block, out of block into TB, TB to heater matrix, heater matrix to water pump then back into filler neck or what?

thanks for any help you can provide.

from faq thread above, http://www.autosportracetech.com/RX-7/rx7stuff.htm then select http://www.autosportracetech.com/RX-7/coolingsystem.htm

wp exit port pushes coolant directly into plug side of block, comes back on exhaust side to wp inlet port, If tstat closed, a bypass is open and coolant goes through pump again. No flow through rad or AST. once well warmed, tstat is wide open and closes the bypass. Hot flow exiting block now enters pump hsg and goes through open t-stat, out lower filler neck to upper rad hose, through rad to lower hose and back tp wp inlet.

TB heater comes from back of block, and is pulled back wp housing inlet.

Heater coil is fed by large line below oil filter, and returns to wp inlet. It always has substantial flow, and always bypasses the rad loop, loweing cooling capacity (unless heater fan is on max).

Turbo cooling starts at the return port for the wp, goes to turbos, returns at wp inlet pipe. Not much pressure drop, so not much flow, and flow reverses at shutdown, making t-stat housing gages jump, but this is very local volume of hot coolant thrmally syphoning through turbos.

AST is functional when tstat opens, and flow goes across top of filler neck and drops to 10mm exit port. Then comes in a 10mm port to ast mid body, and lower hose feeds this flow to lower rad tank, then to wp inlet. To avoid high rad bypass, a .086 pill is intregral to the lower nipple. As coolant expands with heat, pushes air and coolant through ast regulating cap to overflow tank.

thnx, a nice post...

howard coleman