So i have this ongoing issue with my heat in my 92 se, when i first bought the car less than a yr ago i blew the bypass coolant hose, replaced it and the thermostate at that time, summer goes by and in august i blew the upper rad hose, so this time i replace both upper and lower but when trying to bleed the coolant system cant get the fan to kick in and car wants to overheat, so i find out my engine temp sensor is gone, replace it and all is well, now its the middle of winter, no hot air, bubbling sound from behind the dash, so i get a buddy of mine at a lube shop to do an coolant flush today with the machine and than we continue to bleed it at the shop, after 45 mins of running and reving the engine it seems to be good, heat is coming on and the fans kicked in for maybe a min, thermostat opened i would think to and lots of hot air, driving it home now and lost the hot air, like its -36 here and took forever to get the fans to kick in when inside the lube shop, and i think the fans kicking indicate the thermostat opens? i duno... but maybe i should have used an aftermarket thermostat? i bought the oem from nissan or maybe i used the wrong Engine temp sensor? is that possible, im running out of ideas, also i cant seem to find an overflow resevoir for the coolant? shouldnt they be by the battery?

any suggestios would greaty be appreciated guys

 

don't worry about when the fans come on, they come on later than the thermostat opening.
when you bled the car did you do it with the radiator cap off?
it takes a long time to bleed the system when the car is on level ground.
If you can, raise the front end of the car up so that the radiator filler neck is higher than the cowl.

 

ya i sure did bleed it for almost an hr with the cap off after flushing it, and it was throwing lots of heat, but than after driving, nothing, after bleeding it, there was no more bubbles coming out

 

our cars are a little funky, and they need to be placed in as extreme an angle as possible to get them bled, with the nose in the air, and the rad cap off. did you do that as well, or was the car level?

 

no it was level but why would it give me hot air and than not? plus the bubbling behind the dash is gone now, should i change the thermostat again or bleed it again, this is ****ed, also where should the overflow resevoir be?

 

reservoir should be the tank in front of the battery.

as to the rest of it, you said you had heat as you left, but it went away while you drove. you probably got the air to vibrate back to where it was, and block off water flow.

 

well i have no reservoir unless its a black canaster under the battery platform, ive seen pics but i dont have the big yellow one, its messed, ill take some pics soon to show u

 

well, right under the radiator cap should be a hose. follow the hose to its end. if it dumps off, the overflow is missing, you can get another @ a junk yard for almost nothing, or a universal one at your auto parts store.
if its missing, that may explain your loss of heat; water heats up, dumps down the overflow hose (to nothing) and down the road, rather than in the overflow.

that canister under the battery is a vacuum resivoir.

 

ah ok, that hose has a bolt in it, so its tapped off, has been since i bought the car, but this is my first winter with it, so could not having an overflow reservoir be the problem here?

 

That hose is there for the system to suck in more coolant as needed and it also will push coolant back into the tank when the system gets hot. If its blocked off by a screw, when it gets really hot, it could be building lots of pressure in the coolant system. Go get a coolant tank from a junkyard. it goes on the passenger side near the headlight. If you have a VE 5spd, then its infront of the battery by the headlight.

 

Just a FYI people..


Any 3rd gen with ABS= coolant tank in front of the battery..

3rd gen with no ABS=

 

I was waiting for one of your pics to show up

 

ok ill pick up a coolant tank soon, and mine will go by the battery because i have the abs, could this be causing the issues? also the ETS, interchangable between vg and ve? ive also read the temp gauge in the car should hit half way, mine doesnt? thermostat issue? the one in there is not even a yr old

 

one of the coolant sensors controls the gauge, while the other sends info to the ECU. if it doesnt work, you may want to search to see which sensor (and where it is) controls the gauge, and replace it. they are only like $10 or so.

 

I've been trying to purge the air from my maxima's cooling lines as well, unsuccessfully.

Last attempt I had the front end jacked up as far as my jack would take it, and I ran it with the rad cap off, until the coolant got steaming hot, flowing inside the radiator pretty vigorously (I think indicating the thermostat had opened), and even experimented with disconnecting the rad fans while running the A/C to help it heat up quicker (it did seem to work.) I thought I burped a little bit of air, but wasn't confident I got it all.

Sure enough, just recently noticed the "bubbles behind the dashboard" sound after driving the car around shortly after cold starting.

This system should be designed to gradually purge air+fluid out of the rad cap when it warms up (into the overflow tank) and then when it cools down, suck fluid back in from the overflow tank... right? Well I'm wondering maybe if the tube connecting from rad cap to overflow tank wasn't totally air tight, it could let air bleed into the tube, so when engine cools down it sucks that air inside, rather than coolant. Plausible theory?

I've been running it long enough that it doesn't seem to be self-purging. I've got the overflow tank hooked up. No ABS, '89 GXE.

Any quicker/simpler/more reliable method of purging the air out that lifting the front end and running it for ~1 hr? I read about some sort of vacuum device used by professionals - can anyone explain this more or provide link as maybe it's worth a try for me.

My heater is kicking out faint heat, maybe 120 deg... I want it blasting out at 180 degrees. I have no idea what thermostat is in there (but the car runs OK and the temp gauge usually read 1/4 - 1/2 during normal operation.)

 

bought one of these at autozone, havent had any problems with my system. I just dont usually recommend it, because it isnt standard procedure.
http://www.amazon.com/Prestone-AFKIT.../dp/B000CCFY5W
it takes me about 30-45 minutes to burp. I have the "T" mounted on the highest point in the heater system. I can do it on level ground, too.

 

so does anyone think not having an overflow reservior will cause the problems im having with my heat? or what?


that flush and fill seems ok but i just got a 120 dollar flush (paid 0) at a lube shop with the machine and im sttill having these issues, i dont think its because it needs to be bled more..

 

it needs to be bled more.
that is the single biggest problem with poor/no heat.

 

ok, ill do it again than, and as far as having no res for the coolant, is that an issue?

 

Yes, it could, if your coolant overfill spout is just draining out on the ground(i'e.not into some kind of catch can= overfill reservoir) This means your car is constantly losing coolant every time you drive it= low coolant after a while=air in place of coolant.

 

oh no its not draining out, the hose that should go to the res is tapped off with a bolt, the car came like this, is it bad to have it like this?

 

stick the end of the hose into a coke bottle.
if you really want to do it "right" drill a hole in the cap of the coke bottle and feed the hose through it so it almost touches the bottom of the bottle.

 

i have no problem getting a res for my car or using a coke bottle like you suggested, what im wondering is will having the hose tapped off like that hurt my engine or cause my heating issues in the car?

 

I wouldnt do this as a fix, its more of a band aid. the plastic is thin, and may not stand up to the high temperatures of the coolant.

there is a reason that coolant systems are designed with an overflow tank, and not just a hose with a cap (bolt, in your case); to allow the fluid to overrun when it has too much, and suck some in when it needs more. with this critical component missing, it has to find a way out somewhere, and can take it out on the plastic on top of the radiator, or the radiator cap itself. if either of these give, and coolant escapes, when it needs to add to its system, it finds a way to "inhale" and sucks in air, instead of coolant.

 

you are over pressurizing your cooling system by blocking off the overflow hose.

 

ya and i bet thats what the problem is, im gonna pick up res tomorrow if this cold lets up and slap it in and try this out, do you guys have a pic of a ve engine with the res hooked up? i want to see how it sits and what not, it doesnt seem like one would fit, it must be wide and not tall to fit in there

 

^^^^^^^

abs or no abs?

 

i have abs

 

I had an issue of mine after bleeding it, a day or two later i would have no heat. over and over we went. i got a radiator cap with a higher psi and now i always have heat

 

did you try a stock replacement cap first?
raising the PSi is not good, it can cause system damage. It does however raise the boiling point of the system though.

 

Best pics i could find..

http://forums.maxima.org/4481052-post195.html

 

it looks like the vg and ve share the same resivoir (on abs models), what do you think?

 

Yeah, they are most likely the same..The non-abs vg/ve are identical in shape/location also.

 

ah so the bubbling in the dashboard sound when turnin the car off is because of air in my collant system? Ive had a slight crack in my radiator and I will be replacing it very soon. Will I need to bleed the system when I do the radiator install?

sry to post on someone elses thread, didnt want to start a new one with similar problem

 

um.. I should think so. you will be draining nearly the entire system, just by unhooking the bottom hose. (I would almost bet the radiator holds nearly half the coolant by itself, plus the top and bottom hoses)

 

that would be my first guess, yea

 

Follow the procedure for changing the coolant in the MA section of the FSM, after you get the new Rad. It gives you all the steps. As you fill it with new coolant the air will slowly purge out of the system - but I remember it taking a REALLY long time to do it. I could only fill it slowly through the filler neck as the bubles kept surfacing and it would take in the new fluid very slowly from the funnel. It took me 3 hrs to complete it (because I had to drain & fill 4-5 times to get the old green crap out).

I didn't know to put the car on an angle, so it was completely level.

 

wow...ok....so i didn't know that you can bleed the coolant system...but is this 3rd gen maxima specific??? or all older cars..or all cars in general.... just more prone to 3rd gen maxima having air pockets that you can't get rid of..i don't think i bled the coolant in my 4th gen when i replaced the coolant...all i did was top it off..start the car....ran it till it was hot...and when i tried to take the radiator cap off to see if it was full...coolant will try to spill out..that's when i knew it had enough coolant..if it didn't...i would add more directly from where the cap is located or it would just suck it down from the reservoir. (guessing that's considered bleeding it??)

and maybe a dumb question....

This is how you're suppose to bleed the system

Jack up front end...take rad cap off...start car....keep it running till it gets hot..add coolant as needed....but the thing is....wouldn't the coolant spill out of the radiator??? My guess is that if the coolant is spilling out of the radiator cap....that means there's no more air in the system???

I've only changed the coolant on my driveway which has a slight hill..maybe this is the reason i've never had trouble and needed to bleed the system????

To the op.....i would assume that it would have an effect on the air pocket thing...think about the brake system.....if you have no brake fluid in the reservoir....and when you need the fluid (i.e. depressing the brake), what you're gonna get is air since there is no reservoir..again..i'm just applying the brake logic...i can be wrong....cause i kinda feel dumb that i never knew about coolant bleeding... -= \

 

you also need that step I added and made bold. you would like to think the fluid would spill out of the radiator cap, but it doesnt. it simply stays down. I guess there isn't enough pressure to push the fluid up. its pretty cool watching the fluid's current.

as to this being specific on all cars, or what-not, I haven't heard of it before I came here, but it works on our cars.

 

yea..i figured that as much...but man...i really feel like a newb...but now i know!!!!! i think i'm gonna go sob for a bit..