Need help with weird coolant behavior
#1
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Well I had my intake manifold off to finish some porting, and after I put eveything back together and started the car up, my idle was all bouncy. Espcially when its cold but even after it warms up it still wont hold a descent idle, bouncesup to like 12-1500 rpms. So i just figured I had a vacuum leak, or I crossed some vacuum lines or something, but I took it out for a drive anyway, figured Id just have to take it back apart and check everything and put it back together when I had time. Well the next day I wa driving and the low coolant buzzer came on, which was strange because I just made sure the coolant was full and I bled the system after I put the manifold back on. So I popped the hood, and coolant is squirting out of the overflow bottle. why woud the coolant be coming out of the bottle when at the same time my low coolant buzzer is coming on because theyre isnt enough?? And the coolant was actually low, I put like 1/2 a bottle in. I am gonna take the manifold back off today and try to fix the vacuum leak, hopefully this is related to it somehow. Other than this the car runs really well, no smoke, smooth acceleration. Any ideas on what it could be, or if it is related to a vacuum leak in any way. Help would be appreciated. Thanks.
#6
Kinda had/have the same problem. If the overflow keeps getting full, there is a leak somewhere. Check radiator cap (mainly, just replace it with a new STOCK Mazda one), check the little hoses from and to radiator, check thermostat housing for cracks, check heater hoses (very prone to failure due to oil/heat)...![Wink](https://www.rx7club.com/images/smilies/wink.gif)
Simple to fix, but a PITA to discover
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Simple to fix, but a PITA to discover
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#8
Well, I took the intake back off and found a bit of old gasket that I missed removing , so I cleaned all that off. Now the idle is back to normal, silky smooth at 800rpm
But..Took it for a test spin, and abuot 30min later my low coolant buzzer came on again, so I popped the hood, and low and behold there was still coolant squirting from the overflow bottle
. I checked all coolant lines, there isnt a leak anywhere Im faily sure. Also replaced the rad cap. So if anyone has any more suggestions PLEASE help, dont know what to do here
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#9
Engine, Not Motor
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What is the temperature on the guage when this happens?
Don't just check the coolant lines, replace them. Especially the one that goes to the coolant recovery bottle.
Don't just check the coolant lines, replace them. Especially the one that goes to the coolant recovery bottle.
#10
The temp doesnt seem to be goin up, its steady where it is normally, about 1/3 of the way up. ( Stupid stock gauges). Ok, so Ill try replacing coolant lines, but.. I did check all them and Im pretty sure none are leaking. I even revved the engine to see if it was leaking at high rpm's, and It didnt leak anywhere, just squirted aut of the overflow bottle more
. Noone knows what could be causing this??
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#11
Ok, Just replaced most coolant lines. I filled and bled the coolant system again, and took the car out for a spin. Came back after about 15 min of driving, popped the hood, and.......yep ..coolant squirting out of the overflow bottle
*sigh* I have absolutely no idea what to do. I replaced the rad cap, replaced coolant lines, checked over everything, seems to be ok. The car runs really well, idle is smooth and steady, no smoke, smooth acceleration. So I dont think its a major problem, plus it just started after I took the intake off. Getting kinda pissed. Gonna sleep on it, see if i can think of anything. If anyone has any ideas, PLEASE help. Thanks
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#12
You wont believe it, but I think we are in the exact same situation. I have fought this for more than 2 months, and now its back again. I replaced almost everything in the cooling system (rad cap, lines, thermostat, thermostat housing, hoses) and still nothing.
This has happened only once, under hard driving and very high temperatures. Although my problem is not as severe: if I drive around normally, I dont get any coolant overflow. But, the one time that I did drive around pretty aggresively and the temperature was pretty high, the overflow bottle was filled, the temp gauge moved ever so slightly (since there wasnt enough coolant left in the radiator), and I had to stop, let the car cool, and transfer the coolant back to the radiator.
The car does not burn one drop of coolant (i've checked and rechecked) so its not the water seals or corrosion in the housings. Its not the water pump either. It must be something else, but I cannt figure out what....
This has happened only once, under hard driving and very high temperatures. Although my problem is not as severe: if I drive around normally, I dont get any coolant overflow. But, the one time that I did drive around pretty aggresively and the temperature was pretty high, the overflow bottle was filled, the temp gauge moved ever so slightly (since there wasnt enough coolant left in the radiator), and I had to stop, let the car cool, and transfer the coolant back to the radiator.
The car does not burn one drop of coolant (i've checked and rechecked) so its not the water seals or corrosion in the housings. Its not the water pump either. It must be something else, but I cannt figure out what....
#13
Yea, sounds to be about the same as my problem. It does seem to happen worse when driving aggressively, at high rpm's, but thats understandable since the coolant would be flowing faster, you might still be losing a little at lower rpm's, just not noticing it. MY friend had the same problem on his Probe GT. That car has two rad caps, one on the radiator and one on the overflow bottle. Turns out he had them switched and the coolant was flowing in the wrong direction kinda, just pumping it out of the overflow bottle. Too bad we dont have two caps
I'm just getting so Frustrated, I have no clue what the problem is, and Im sick of having to carry around a bottle of coolant and a screwdriver for when my buzzer goes off
Well, if you find out what the problem is please let me know. No gurus can help us out here??....Ted??
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#15
No no, no smoke on startup, nothing. Smooth idle too. (Although I wish I had that FD even if It did have a bad coolant seal
...
) No, it just squirts out if the little pinwhole on the overflow bottle, while Im driving and for a few minutes after the car is shut off. Its really strange.
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#16
hmmm...
the only thing I can think of is the Thermostat not opening up, or backwards or something.
Its not making any sense...if everything is ok then why?
Crazy Haunted RX-7's
Its not making any sense...if everything is ok then why?
Crazy Haunted RX-7's
#19
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When cold, start your car and remove the filler cap on the thermostat housing... Do you see bubbles coming up? Rev it up a tad...
If you see bubbles, then sniff them... Smell like exhaust? If so, then the water seals inside your engine are shot, allowing the compressed air inside the combustion chamber to leak past, and into your coolant system. Since this compressed air is under a *LOT* more pressure than the coolant system, it wins, and the air flows that way, instead of the reverse (which would probably happen after you turn your car off...)
This gas forced into the coolant system will force SOMETHING out because of the increased pressure. The only way out is the overflow bottle...
When you take the cap off after it's low, does it smell like exhaust in there?
Hope that's not the case!!!![Frown](https://www.rx7club.com/images/smilies/frown.gif)
-Tesla
If you see bubbles, then sniff them... Smell like exhaust? If so, then the water seals inside your engine are shot, allowing the compressed air inside the combustion chamber to leak past, and into your coolant system. Since this compressed air is under a *LOT* more pressure than the coolant system, it wins, and the air flows that way, instead of the reverse (which would probably happen after you turn your car off...)
This gas forced into the coolant system will force SOMETHING out because of the increased pressure. The only way out is the overflow bottle...
When you take the cap off after it's low, does it smell like exhaust in there?
Hope that's not the case!!!
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-Tesla
#20
Originally posted by KNONFS
Man I really don't know, I had a similar problem and it turned out to be corrosion on the housings. Have your system check\pressurised.
Man I really don't know, I had a similar problem and it turned out to be corrosion on the housings. Have your system check\pressurised.
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