94 Vert overflowing radiator problem

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crono774
Posts: 14
Joined: Sun Jan 08, 2012 11:19 pm
Car: 2004 Subaru STi- DD
1990 240sx Hatch- Side Project
1994 240 Vert- Wifeys Project/DD
Location: FL

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Hello NICO members. Ill just jump right into it; recently bought a 94 convertible for my wife and needless to say the car was neglected and needed a little tune up. The first thing me and a friend did was change the water, thermostat, water pump, rad cap, and temp sensor. The water was just plain water/goop so we figured we need to change all of it at the same time to be on the safe side. couple days later she said she could smell coolant. found out it was losing about a cup of water a day. so we keep filling it back up; then a week later white smoke out the exhaust.

Changed the head gasket using many forums on NiCO. everything is back together did an oil change, filled up the radiator with just regular water (for now), started it up and no more smoke out the exhaust :mike . start to burp the system after reading "how to" on here. everything was going good and car had warmed up to operating temperature and i had a funnel over the rad i kept full with water. I had been going at it for 20 mins letting all the air out, all of the sudden i hear the ac fan kick on and the water starts over flowing over the funnel. i check my temp inside the car and it reads normal (3rd notch). i turn the car off and all the water in the funnel instantly gets sucked back into the rad. :wtf2: the last thing i need is the car overheating again and doing more damage.

What could cause this? i asked a few people around here they said bad thermostat so i took it out today tested it in boiling water it opened and 20 long mins later it started closing when the water started to cool. so im lost... any help would be great!


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biggie
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Joined: Wed Jul 24, 2002 2:31 am
Car: '16 Q70L/'14 Q60S Vert/'19 Armada/'09 FX35
Location: Clemmons, NC

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Sounds pretty normal actually. Weird that it did overflow, but sounds like the thermo opened and the water pump was flowing through enough to push it out.

If it ran for 20+ mins without overheating everything should be good. Just make sure the rad is topped off and drive it.

crono774
Posts: 14
Joined: Sun Jan 08, 2012 11:19 pm
Car: 2004 Subaru STi- DD
1990 240sx Hatch- Side Project
1994 240 Vert- Wifeys Project/DD
Location: FL

Post

i gave that a try last night figuring it was just a fluke one time deal. so i put everything back together filled it up w. water and burped it again. took it for a spin and about 1/4 mile down the road i could hear the ac fan kick on again and water flowing into the over flow. i pull a quick u-turn and as im driving back the temp gauge is pegged on hot...

after letting the car cool down i pressure tested the cap (which is new) and it held the 13ish psi... and the rad took about 2 cups of water. :confused: went to bed after that bc i was cold and it was 1am lol. so im lost what else could it be?

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-RJ-
Posts: 2469
Joined: Wed Aug 09, 2006 4:26 am
Car: S13 Convertible, 99 Frontier, 03 Sportage, 96 Protege
Location: Virginia Beach

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I had problems like that with my vert and what I learned is to never buy crappy thermostats from advance/autozone/pepboys. Ive went through 2 Stant thermostats in 3 years. I bought an OEM one, though it was $25 at the dealership, and never had a problem. Even the OEM is much more beefy and looks better made

Image
Image<-- Stant

crono774
Posts: 14
Joined: Sun Jan 08, 2012 11:19 pm
Car: 2004 Subaru STi- DD
1990 240sx Hatch- Side Project
1994 240 Vert- Wifeys Project/DD
Location: FL

Post

i took off the thermostat and tested it and opened and closed just fine. i got it from autozone. i just dont get why it would be working one sec and keeping temp normal, then the next min it closes and the rad overflows... :ohno: im thinking of just taking the thermostat out and leaving it out and seeing what that does.

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biggie
Moderator
Posts: 10330
Joined: Wed Jul 24, 2002 2:31 am
Car: '16 Q70L/'14 Q60S Vert/'19 Armada/'09 FX35
Location: Clemmons, NC

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Can take it out. If that fixes the issue then yes its a bad thermo. I too only run OEM ones.

If it still overheats then there still is an air bubble in the system. When using the funnel, be sure to either jack the front end up or park on a hill to get the front end up higher.

crono774
Posts: 14
Joined: Sun Jan 08, 2012 11:19 pm
Car: 2004 Subaru STi- DD
1990 240sx Hatch- Side Project
1994 240 Vert- Wifeys Project/DD
Location: FL

Post

Yeah i had it jacked up plus my driveway is at an angle and turn the heat on... the whole 9 yards. lol also someone said something about the heater core being clogged and thats making it over flow? idk how that would do that but i thought i would mention it. have to go to work soon so ill give that a shot tonight and update this post with what happens.

crono774
Posts: 14
Joined: Sun Jan 08, 2012 11:19 pm
Car: 2004 Subaru STi- DD
1990 240sx Hatch- Side Project
1994 240 Vert- Wifeys Project/DD
Location: FL

Post

Update... Bought the nissan thermostat put it in still the same prob. borrowed a leak down tester and quickly found out it was leaking in cylinder 2. It caused small bubbles in the coolant and water mixed in the oil. I was tired of messing with this motor. Picked up another kade, ecu, harness, and auto trans with 66k miles for 500. Removed all emission garbage and dropped it in. DONE.

Lesson learned


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