2003 350z overheating HELP
hey justin
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From: missouri
Thanks for the input everyone. Ok I have a few questions. I will change out the thermostat this weekend if I have no luck. When the car gets to the top of normal temp almost to high the boiling does come from the overflow just FYI.
1. The bottom radiator hose doesn't ever seem to get hot ever? Thermostat not opening for sure or at all?? I ask because the car seems to sit at normal temp a longtime before overheating.
2. I understand air lock can stop the thermostat from opening but if I did have a blown gasket would the stop the thermostat from opening?
3. Is there anyway to know for sure I don't have a coolant and oil running together. ( a blown head gasket)
Thanks again.
1. The bottom radiator hose doesn't ever seem to get hot ever? Thermostat not opening for sure or at all?? I ask because the car seems to sit at normal temp a longtime before overheating.
2. I understand air lock can stop the thermostat from opening but if I did have a blown gasket would the stop the thermostat from opening?
3. Is there anyway to know for sure I don't have a coolant and oil running together. ( a blown head gasket)
Thanks again.
Last edited by Chris350z03; Sep 18, 2015 at 04:40 AM.
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From: ZdayZ
Mark your coolant overflow with a piece of tape at water level. If your head gasket is bad it WILL consume coolant.
Mark when cool, read when when cool, because the level changes with temp.
Mark when cool, read when when cool, because the level changes with temp.
IDK what it is about these cars, maybe there's pockets in the system prone to trapping air, or the way everything is routed. But it also took a very long time for me to bleed the air out of my system completely. Just when you think you get it all, more bubbles out.
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Joined: Sep 2015
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From: missouri
I got to agree!! I got more bubbles out this morning 2 times so far on the bleed heat up rev cool down bleed.
Thanks for the input everyone. Ok I have a few questions. I will change out the thermostat this weekend if I have no luck. When the car gets to the top of normal temp almost to high the boiling does come from the overflow just FYI.Mine did same thing
1. The bottom radiator hose doesn't ever seem to get hot ever? Thermostat not opening for sure or at all?? I ask because the car seems to sit at normal temp a longtime before overheating.Car would sit for a bit before overheating yes. If bottom hose doesn't get hot ever you have a T-stat problem
2. I understand air lock can stop the thermostat from opening but if I did have a blown gasket would the stop the thermostat from opening? No
3. Is there anyway to know for sure I don't have a coolant and oil running together. ( a blown head gasket) Compression test and look at your oil for milkyness
Thanks again.
1. The bottom radiator hose doesn't ever seem to get hot ever? Thermostat not opening for sure or at all?? I ask because the car seems to sit at normal temp a longtime before overheating.Car would sit for a bit before overheating yes. If bottom hose doesn't get hot ever you have a T-stat problem
2. I understand air lock can stop the thermostat from opening but if I did have a blown gasket would the stop the thermostat from opening? No
3. Is there anyway to know for sure I don't have a coolant and oil running together. ( a blown head gasket) Compression test and look at your oil for milkyness
Thanks again.
It's funny how people come here, ask questions, and then fail to follow the advice offered, even when that advice has been well-proven. These cars have been around for long enough that these issues to have been resolved years ago. Not too many Z33 mysteries left at this point.
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From: Miami, FL
I didn't really have to start a thread about my radiator probs just a simple search on Google and through this forum should give you all the info needed for the radiator bleeding procedure this is just a regurgitation thread of previous threads
A shop told me to replace thermostat, I didn't believe that was the issue and I ended up saving money end of story. Shop does mechanical work for a living yet I don't even have a year worth of mechanical experience yeah shows how little I know.....
A shop told me to replace thermostat, I didn't believe that was the issue and I ended up saving money end of story. Shop does mechanical work for a living yet I don't even have a year worth of mechanical experience yeah shows how little I know.....
Last edited by Justin100; Sep 18, 2015 at 09:50 AM.
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From: Illinois
No Z owner should be without this!
or better knows as an Airlift Coolant leak test/fill tool... The Z is prone to air pockets and this is the best solution. Air will always find the highest point to settle and this will fix that problem. Also a thermostat does not read temp, your Temperature Sensor will do that
Hope you have the problem solved by now.
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From: Illinois
You can check the cooling system for Carbon Monoxide gases with a Carbon test kit for a head gasket. (Not always definitive) Compression test is ok for checking Rings, I would recommend a Leak Down test, its a more accurate test, If you hear whooshing/howling at the oil filler cap, you are losing compression through the rings. If you hear it or even feel puffs at the tail pipe, it is your exhaust valves. If you can hear near the throttle body/intake manifold, it is your intake valves. If the results are inconclusive, it is probably your head gasket.
Not being a know it all / Just trying to share a little info for anyone else that may be interested. 20 years of auto mechanics and still learning
Not being a know it all / Just trying to share a little info for anyone else that may be interested. 20 years of auto mechanics and still learning
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From: Seattle, WA
Amazon.com: FJC 43610 Radiator Coolant Vacuum Refill Kit: Automotive
or better knows as an Airlift Coolant leak test/fill tool... The Z is prone to air pockets and this is the best solution. Air will always find the highest point to settle and this will fix that problem. Also a thermostat does not read temp, your Temperature Sensor will do that
Hope you have the problem solved by now.
For the shadetree mechanic, the Lisle funnel is the next best way to do a radiator flush.
Doesn't our thermostat have an anti-airlock valve (little hole for the air bubbles to pass through) on them?
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From: South Alabama
Over heating
Hello all new to posting but been reading posts on here for a while big help.
Ill try to make this short. I've been reading post after post trying this and that and now I'm at a loss. My car over heated one day to "High" after running warm ( but with in the normal area ) for a couple of weeks. I let it cool down and checked the radiator and noticed it was low. I bought some coolant, it needed about half a gallon. I thought ok that was my problem and went on my way. No luck, it over heated again with out leaking any coolant. So I get on 350z.com to see what you guys thought and I read a lot of bleeding problems on the 350z's. So I bleed and bleed and bleed I feel 80% sure there is not a bubble left over a 5 day period. The car takes a while to overheat now but still works toward the H. I rev 2.5-3.5k the engine and it goes down to about middle stays there for a while then slowly works back up, rev then it goes down a bit then slowly goes back up. takes about 2-3mins to go back up. Can anyone help please.
I would just like to know what or how I could diagnose the problem for sure to bleeding , TS, water pump or head gasket.
No leaking coolant
both fans work and kick on
bottom hose seems never to get hot (car takes a long time to overheat after reaching normal temp stops right at the 1/3 temp spot)
heater works in the car
no white smoke or the tail pipe
doesn't seem to be coolant in the oil
I did the bleeding on an incline using the bleeder and R-cap
Car has 120k miles and I'm pretty sure as never been flushed
Change thermostat and run straight full strength antifreeze.
Any help would be appreciate.
Thanks!
Ill try to make this short. I've been reading post after post trying this and that and now I'm at a loss. My car over heated one day to "High" after running warm ( but with in the normal area ) for a couple of weeks. I let it cool down and checked the radiator and noticed it was low. I bought some coolant, it needed about half a gallon. I thought ok that was my problem and went on my way. No luck, it over heated again with out leaking any coolant. So I get on 350z.com to see what you guys thought and I read a lot of bleeding problems on the 350z's. So I bleed and bleed and bleed I feel 80% sure there is not a bubble left over a 5 day period. The car takes a while to overheat now but still works toward the H. I rev 2.5-3.5k the engine and it goes down to about middle stays there for a while then slowly works back up, rev then it goes down a bit then slowly goes back up. takes about 2-3mins to go back up. Can anyone help please.
I would just like to know what or how I could diagnose the problem for sure to bleeding , TS, water pump or head gasket.
No leaking coolant
both fans work and kick on
bottom hose seems never to get hot (car takes a long time to overheat after reaching normal temp stops right at the 1/3 temp spot)
heater works in the car
no white smoke or the tail pipe
doesn't seem to be coolant in the oil
I did the bleeding on an incline using the bleeder and R-cap
Car has 120k miles and I'm pretty sure as never been flushed
Change thermostat and run straight full strength antifreeze.
Any help would be appreciate.
Thanks!
Any help would be appreciated
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