I replaced my AST and I just want to make sure that I am burping the system correctly. So I refilled my coolant through the filler neck until i could pretty much see the coolant in the AST, then took it for a little drive, too the cap on the AST off once it was cool, then added a little more coolant to the filler neck. I musta put a little too much cuz there was a little coolant on top of the AST after i took my second drive, it looked like it might have sprayed a little from the AST. so i waited for it to cool and then took the caps off again and removed a little bit of coolant. Took a third drive, everything was fine when i got back, waited for it to cool and took the caps off again.

Now i'm going to the store about ten minutes away and then I'm gonna take the caps off when I get home after it cools. My only concern is I'm going on an hour drive tonight and every time I get home from driving my engine bay feels real hot, and the AST is really hot too. My gauges inside the car read the same as before I changed out the AST, so I feel like there still might be air in the system. I could be a moron too and I just think it's really hot when infact it's normal, but I figured I'd come on here and ask you experts if what I am doing is correct. Thanks for you help guys.

-Nick

 

there are a few useful links if you do a search.. but i have never heard of anyone do it the way you did, not saying its wrong; just diff.

i put coolant through the filler neck close the cap and squeeze or pump the bejesus of the upper radiator hose. that should circulate the coolant. pump for a good 15sec than remove the radiator cap and top off with coolant as necessary.

once you feel that you've put enough coolant, remove the coolant hose located near the UIM(upper intake manifold) of throttle body. with the radiator cap on, pump the radiator hose again and you should start seeing coolant come out the hose you just unplugged. while holding down the upper radiator hose(or while squeezed) plug the coolant hose back into the uim.


now you should have taken out more than 95% of the air in the system.

drive it around for a bit, wait for it to cool and top off as needed.

 

I generally run the car for several minutes with the cap open, turn off and refill. I do this two or three times as needed and then do a short drive around the block to get the car to get up to normal operating temperature, park it, and refill when it has cooled down.

 

Moconnor has the Right Idea.
There is a Funnel system made By LISLE that alot of Rotary Guys Swear by.it attaches to your Rad cap "thingie" and allows you to run the car,and get the engine to opens it's thermostat..the coolant Expands goes out and doesn't flow all over the engine as the Funnel will Hold the Excess being Expelled out.
once the thermo is opened and the air is out/burped,you can Take the Funnel off and seal the Cooling system.It works like a charm on the FC.
I am not Positive about the FD's System but sure that it should be similar.

 

This is whaat he is refering to, I wish i would have had one along time ago makes burbing the ccooling system alot easier.

http://www.wescotools.com/p-9906-lis...ee-funnel.aspx

 

One thing that helped me recently was reading on the forums to remove the coolant hose that plugs into the back of your TB.

I refilled mine until a little spilled out of that TB hose, plugged it back up, and ended up needing to add VERY little coolant over the next day.

I also use one of those filler funnel things (bought mine from pelican parts for like $25 I think) worth it's weight in gold.

 

If coolant has sprayed in your engine bay after driving, you might think about getting new caps for your AST and radiator.

Also, take a close look at your hoses and clamps. Sometimes a split in a hose is almost invisible until it's pressurized

 

You can't overfill your coolant system. So you probably have air in the system and it got hot enough to build enough pressure to go past the cap on the ast. Either that or you didn't get the hoses tight. You should not have removed fluid from the system. I don't recommend you go on an hr drive, and if you must bring lots of extra water. Everyone has good advice on bleeding the system. I also recommend running higher pressure caps then stock. I run 16 psi on mine. This allows for a higher boiling point. I rather my system keep the coolant in if it gets on the hotter side. Rather then dumping it all out into the overflow or ground.

 

yeah, if you're AST is spitting out coolant, you have a leak or sealing problem with the cap. better check that out. Also, you never fill the coolant from the AST. its always from the filler neck next to the crossover pipe. which is where you should install this funnel to properly burp the cooling system.

this link could be found in the FAQ
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/radiator-cap-funnel-eliminate-air-bubbles-342309/

put the funnel on the filler neck, keep the engine rev'd at about 5k for few seconds and fill coolant as you see it decreases. repeat until the coolant level no longer drops from the filler neck

 

ok, so i burped it just like moconner said right before i left. took the hour drive no problem, also brought a ton of water just incase. I think the little coolant that was on top of the ast was just like dudemanownsanrx7 said, i probably had air in the system and since im only running a 13psi cap and not a 16psi cap a little coolant maybe escaped.

anyway, everything worked out, thanks for your help everyone. by the way, goin to order the funnel system by lisle sometime next week. looks like it'll really help.

Thanks again

Nick

 

That's the technique I always use. No need for funnels or a bazillion refills after the initial fill.

 

I used the TB hose once - but did not find it any better than running the car once or twice in the garage with the cap off. And I'm not fond of disconnecting coolant hoses if I don't have to, particularly ones that are a PITA to reach.