lukecrabtree

Hi everybody! Just purchased an fd after years of wanting one! Forgive me in advance I'm not very clued up on the mechanisms I just drive.

Few things I need help with;

Gurgling noise when turned off. Now I realise there must be air in the system somewhere so I let the car cool and turned it back on with the cap off to release some air. Should my fluid levels be that high and that colour?(pic1)

mizboo102

Looks rusty and if that is the case, no it is not supposed to be that color. The height is fine. I would flush the system and put good coolant in it. Don't forget to drain the coolant from the drain plug on the block. Also, look into getting an fc thermoswitch to turn the fans on sooner.

lukecrabtree

Thanks very much mate. Forgive me, the switch is temp controlled so comes on automatically? Thanks

OG BBF

Height of fine, colour totally dependant on colour used by previous owner. FD from factory used green glycol based coolant if I remember but over the years this doesn't get followed. I would do a complete coolant flush and fill. Gurgling most likely is air in the system which isn't good for these cars as heat spots can occur and do a lot of damage over time.

Plenty of guides on here to flush and fill an FD, or follow the FSM guidelines.

mizboo102

Yep, the fc one replaces the fd one directly, just turns on 10*C cooler

Here is a good thread: https://www.rx7club.com/3rd-generati...system-906142/

lukecrabtree

Thanks guys I appreciate this! Would it be worth buying a different air separation tank or no difference ?

HadaVette

iTrader: (3)

The stock plastic Air Separation Tank (AST) is prone to failure, so replacing it with an aluminum aftermarket one is a recommended early reliability mod. Also, the fluid should always be full at the AST, check your level and add coolant at the higher cap on the block.

Good recommendations above!

lukecrabtree

👊🏼thank you !

OG BBF

a note on the above and there will be mixed reactions and opinions, but you may want to consider deleting the AST altogether. I know many will say Mazda put it there for a reason etc but deleting mine was a godsend....simplified cooling system, no worrying about leakages and just gives you a cleaner bay. What I will say is if you do this mod.....you must fill and purge the air thoroughly.....it took me close to 2 hours to fill my system and I literally poured a bit, pumped the rad hoses till the water dropped and repeated....once the water stopped dropping and air was no longer coming out I ran the engine and cranked the heater on....warmed to temp.....allowed to cool and repeated the process.....doing it right will ensure great temps and no need for that tank.....my car never goes over 85c even on track at a push....maybe tickles 86 but never over....and that was in hot weather!

As as they say, the fastest short cut to anything is doing it right the first time.