sk8world

iTrader: (5)

First I have searched many threads trying to find any help. I am not trying to ignore the facts but just want to make sure before I pull the motor.

I just installed a fresh streetport. I did note that it had a good bit more preasure in the cooling system at first start up than Iexpected. Also the "add coolant light and buzzer" would never shut off. Coolant level was fine so I ordered a new one and still same effect. So I just took it that it had a short in it that needed to be fixed...
Had my tuner come in to town and do his work a few weeks later. Car was fine for street tuning then on to the dyno were it was also fine. Made 25 pulls at the dyno on a pretty hot day. Drove the car home and parked it for 2 days. Started it back up and drive around the block (giving my kids a ride) the car over heated? Opened the radiator and had an air pocket. Added water and it was fine held temps perfect. Even went out for some 23psi (C16) street driving later and temps were rock solid. Next day car was fine also. Then the following day it started to over heated again due to an air pocket causing the thermo not to open. I added more water went for a street drive and it started to get a tad warm (mid 90's) but if I went onto boost it would cool a few degree's, did that a few times? So I wanted to verify the NEW oem thermo was not the culprit and removed it. made a gasket and went for an easy drive on a 90 degree day. Car at first ran very cool as expected then started to get warmer little by little, say 85-little by litle until 100 and held there steady. Again I opened the cap and there was an air pocket??
Now, I have NO coolant leaking external! 100% on that. I have NO hard starting, no wet plugs,no white clouds (coolant in exhaust), coolant seems clean-no signs of gas in it. I DO have more preasure in the coling system then I would think is normal by how the top hose feels, I do have preasure pushing coolant into the over flow tank replaced by air in system. I did the funnel-air bubble test and DID see some small bubbles-and a few big bubbles. they would come and go. Not always present. I also noticed preasure or coolant movement in the cooling system with the water pump pulley disconnected? I feel I have worked all the air out of the system but mabye not-tried all the tricks!
I guess I should have put my setup on the top.. Single turbo-fmic-koyo-and ast removed. Now, I did not have any signs of over heating with my old motor and this was with the same setup. Car did sit garaged for 1+yr with no coolant. I do not want to pull the motor but have no problem doing so, just want to make sure it is a coolant seal first. It is under warranty.
Any ideas PLEASE let me know! Thanks, Mike

Liem

Try filling the coolant with the coolant line that runs to the throttle body disconnected. You can also try pouring coolant through that same disconnected coolant line until the system is full. This will force air out when pouring coolant in, both ways.

sk8world

iTrader: (5)

I eliminated the tb coolant long ago.

sk8world

iTrader: (5)

I also pulled of the cap on that nipple that use to feed the TB and coolant flowed steady from it but I did not keep adding coolant. Maybe I should try that? I am also going to try a leak down test this weekend.

gracer7-rx7

iTrader: (16)

you forgot to read the FAQ stickied thread. i think its the 5th one down
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/faq-3rd-gen-other-useful-links-68640/

then go to this thread
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/radiator-cap-funnel-eliminate-air-bubbles-342309/

Zebb

Reconnect your AST goddammit! Its there for a reason.

Herblenny

iTrader: (13)

Mike, Do the leak down test overnight (don't over pressurize it) and see if you are loosing any coolant.

When I blew my coolant seal, I had no sign of it except for air pockets and ultimately over flowing reserve tank.

Good luck!

sk8world

iTrader: (5)

Phil, You say over night but I have heard 15 minutes? I would imagine all cars would lose preasure overnight.

RaPtOr-T

sk8world

iTrader: (5)

l know way too many guys running without the AST. I ran this way before this motor with no problems. I would agree if the car was a track car - autocross or daily driver it would be a worthwhile to keep on. But my car sees only 2-5k a year max. Mostly at the drag strip or street racing were the car gets to sit and cool often..

sk8world

iTrader: (5)

I stand corrected on this.. I would think the heat would be the cause for preasure build up and the cooling effect would be were the preasure is dropped.? Anyway I put a tester on it tonight. Pumped it up to 20psi and so far after 15-20 mins. it stayed very close to the same, after maybe 1 hour it dropped 1-2 psi? I am going t leave it on all night but just wondering if there should be any if at all how much of a preasure drop????

Another thing I read was the over flow tank should not be past full. Well after the first over heat that could have been air in the system that caused it too push coolant to full in the over flow tank I did not give it a chance to pull any back in yet I just filled the radiator back to the top. End result a full radiator and an over full overflow tank. Not sure if this can cause my problems but just a thought.

sk8world

iTrader: (5)

I have been having a cooling system issue with a new motor. Thought I had fixed it (loose colant sensor) but still having issues. My question is: Is it possible to have build in pressure the system by other than a combustion (o-ring failure) leak? Reason I ask is at start up I notice my hoses have much pressure right away. Not always but if I start the car then check the top radiator hose, if very hard (pressure) then it will be due to air in the system and cause the thermo not to open then my temps creap up. If I open the radiator and let the air out (some coolant will also come out) then the thermo opens and it will drive with perfect temps. I have driven it for over 1.5 hours after doing this and it stayed dead on 85 to 86 degree's Celcius.
I ask this question because I did a pressure leak test and it held 20psi for over 2 hours. Then I lowered the pressure to 15psi and it held for a day! Then I did a vapor sniffer test ( checks for cumbustion gases in the coolant) which it passed 6 out of 6 times. In fact I did another today and again it passed. So I know if there is a leak it can not be an o-ring. I also pressure tested the radiator cap and it passed. I do not have the air seperator tank on anymore (ran this way for 1 year on my last motor) but I do not think this could be a factor. I have not pulled the over flow tank it check and make sure it is not clogged but I did replace the line to it. The thermostat is new (Mazda). Almost all lines are new. Turbo has only 2k miles or less and is a garrett gt40r so I can not believe it could be the cause. I have spent hours upon hours multiple times trying to get all the air out of the system so I eliminate that too. I really just expected to fail the presure test or vapor test and blame it on a coolant seal but now I am just puzzled.
Any more ideas?

adam c

iTrader: (2)

First, why don't you try to write something that is readable? The mess you have written above is extremely hard to read. Sentences and paragraphs are actually part of the English language.

From what I was able to decipher, your system holds pressure. What is the problem?

sk8world

iTrader: (5)

I am not even going to bother responding to the post above. If you do not have anything to post that will help then keep it off this thread. I do not want this to be a place for guys to build there post count nor be a smartass.

Herblenny

iTrader: (13)

PM me your number and I'll try to step you thru.. I have an idea..

PHIL