I also forgot to mention this... When I have the heat on high/blast it just blows cold air. It doesn't matter if I'm at idle or driving. I have no heat.

 

It doesn't make any sense to me that the car overheats quickly with the radiator cap on, but takes a long time when the cap is off. Interesting...

If the heater core is not plugged, that means that the coolant level in the engine is low. The heater core is the high spot in the cooling system and air gets trapped in the heater core.

Since you have a new thermostat, put it in and see. But I am beginning to suspect the water pump.

 

Agreed. First thing to check is coolant level, and burp air out of system as I've mentioned before. With no heat in cabin and overheating symptoms, that means no flow which could be a bad water pump or clogged heater core.

 

Guys I did not see the 2 prior posts - did not see there was a page 2.

Anyway... I bought a new Rad Cap at Nissan Dealership yesterday and put on today. This did not work. I made sure Radiator was full. She got hot after just a few miles. I pulled over, let her cool, took cap off, added water as much as possible while idling, left cap OFF, and drove a lot further than I could have with the cap on.

I can drive pretty far if I leave the cap off. I just have to pull over every 8-10 miles and put more water in the radiator because obviously the water bubbles out and the temp gauge goes up. That's when I pull over, let cool, add more water, and drive again.

I've parked on an incline and added water with cap off and burped for 20 minutes with heat on blast. I've done this 3 separate times. The top hose gets hot. The bottom hose stays cool.

There does seem to be a clog. I mentioned these things before but this is a long thread. Just some notes:

* I "fixed" A hard to get to leak a few months ago with Bar's Leak (I know I should not have done that.)
* Radiator fans do go on
* Heat only blows cool/cold air - not even warm air.
* I took both radiator hoses off and flushed radiator with water. Theer is no clog in the radiator.
* When car is warmed up/running the top hose gets really warm/hot to touch and bottom hose is much cooler.

It seems like the fluid is not flowing through the system. It's like the fluid being added is only staying in and coming out of the radiator.

 

By the way there is another thread that is titled: Overheating 4th Gen

His diagnosis is the same Exact problem as mine but I don't know how or if it was ever resolved. The thread kind of ended without a final response.

By the way is a water pump replacement a big job? My buddy does all my work. He's very good. He's done my plugs, Coil packs, Knock sensor (in about 15 minutes,) valve cover gasket, harmonies balancer, alternator, starter, etc...

Wondering about cost of water pump and how long does it take for a person to replace (that's why listed all the things he's done?) He knows the Max well.

Thanks guys.

 

I'd say that a water pump replacement is a medium difficulty job. Of the list you provided, the alternator is probably the hardest thing your friend did. I'd say the water pump is notch more difficult than an alternator. Have you and your friend looked at the FSM for water pump replacement? (see link in my signature below the picture) The removal and installation is spelled out in great detail with clear instructions. I bet your friend you could it.

I hope it's just your thermostat now, but it kind of sounds like you have two problems. One being a bad thermostat since the top hose is hot and the lower hose is cool, and a blocked heater core/bad water pump since you don't have heat in the car. Obviously just do the thermostat first, re-burp the system and hope that fixes everything. Once you fix it, please do post up your solution so you may help others in the future.

 

WIZARD - thank you.
1 quick question... I'm looking at your sig. I see a pirate monkey but where is the link below the pic you're talking about? Sorry bud. I don't see it.

 

With all your given details (car overheating, no hot air from heater core, thermostat not opening, burped air several times, radiator not clogged.....) the only two possibilities is the water pump is gone or your cooling system is clogged. The thermostat will only open when hot coolant reaches it from the radiator bypass pipes. Since the hot coolant is not reaching the heater core I'd presume it's also not reaching the thermostat.

Before replacing the water pump try back flushing your cooling system. I've back flushed my system every 2 years over the last decade using the Prestone Flush Kit. Back flushing using a garden hose is much easier and cheaper than replacing the water pump. After back flushing is complete fill the radiator with distilled water. After it warms up rev the engine a few times then check to see if the lower radiator hose gets hot. Drain and warm up at least 2 more times with distilled water to remove the tap water. If this solves your problem then drain and fill with a gallon of 100% antifreeze. I've used the Nissan Green for the last decade. It costs $25 per gallon at my local dealership.

If the thermostat and heating core still don't work then it's time for a water pump replacement. As the WIZ said the water pump replacement is a medium replacement a little harder than replacing the alternator.

 

You're welcome. The pirate monkey is not my signature, it's my Avatar. My signature is below what I post and is a picture of my car. Signatures only show up one time for each member per page, so you may have to scroll towards the top of the page to find my first post on any given page. If you don't see my signature or anyone's signature for that matter, it means you have the 'show signature' option turned off in your user cp settings.

Fakie and CS_AR also have links to the FSM in their signatures. Anywho, here is a direct link to the FSM. Click me

For water pump replacement, you want the LC section. specifically page LC-9

 

Put a 3/8 quick release adapter in the heater core hose and stick the quick release on it from your air hose/compressor. I blew out the core on the forester and its pretty new. Weird. Good luck.

 

OK I just saw a new thread/original post from 2012... It goes like this:

Well I hate to start a whole new thread for this, but after searching and searching for the past few days, I really haven't found any other threads just like it.

The problem I have is that my maxima is still overheating after changing the water pump, thermostat and radiator cap. The heater blows cold air at 85 degrees on the highest fan setting and the fans run faster than I've ever heard them spin before. I tried bleeding the system this morning and all I got was a lot of steam coming out of the radiator fill hole. The upper hose was very hot and the lower was cold at the bottom and hotter at the top closer to the thermostat. A couple days ago I took the radiator out of the car and ran hose water through it. It seemed to flow just fine in both directions. None of the hoses are collapsing as far as I can see.

So, after reading all of that, does anyone have any ideas on what could be causing the problem? Is there any way a radiator could seem like it flows water fine with hose water but have restricted flow of the coolant/water when in the car? Possibly because of being pressurized? I also thought about the heater core, but wouldn't both radiator hoses still get hot if the clog was back there?

I've seen a couple threads ending in successful fixes of similar problems by replacing the radiator, but I don't feel like throwing more money at the problem unless I have the support of strangers on the internet

This is me now... I also took off both hoses and ran water through it and there didn't seem to be a clog. Gues what this guy's problem was? Radiator.

Other people were giving him the same advice I've been getting on this thread.

I'm wondering if the Bar's Leak clogged up the radiator. I put Bar's Leak in a few months ago cause I had a pinhole leak between the engine and windshield. After a few days the leak was fixed but I'm wondering if some of it settled in my radiator and is slowing down flow? If you read his post he also ran water through and it seemed fine but it turned out to actually be the radiator. Now the radiator I have is less than 2 years old but, like I said, I put Bar's Leak in it.

 

I just took the Radiator out and blew a hose on it from all ends. It seems to be clear.

 

Your ***** not plugged. Every single symptom you've had points to the water pump impeller dealing destroyed including straight water in freezing temps.
YOU HAVE NO FLOW BECAUSE THERE IS NO PUMP!!

Stop treating the symptoms and treat the problem.

 

Since you pulled the radiator, you should have pulled the thermostat and tested it too.

 

Check out the following diagram

 

This picture just keep coming to mind.

 

Captain Chaos, any update?

 

Bad heater core or bad heat control valve?

 

I was supposed to get the Thermostat replaced yesterday but I could not do it yesterday.

I don't know how to pull a Thermostat but I could look it up. Pulling the Radiator is like my limit with car repairs.

I have a good feeling ASAND1 is right.

I know this is a long thread but the problem started like this: I tried to start my car in the morning like usual (couple weeks ago) and a loud nasty sound was heard when I tried to start the car. It would turn over but not start and the sound was aweful. I tried turning over too many times and killed the battery. I jumped the car and then all of a sudden she started like usual. There was no more nasty sound.

The night before this happened it was the coldest night of the season so I think water froze. I planned on putting 50/50 in her that day cause I had just been putting water in cause of the leak I had months before.

I typed some of this already but just in case someone did not read the whole thread.

Can I get aftermarket Water Pump? Once I get her back to normal I will probably sell. I know Rad Cap & Thermostat should be OEM/Nissan parts. Water Pumps are fairly inexpensive on EBAY.

 

He might as well pull it to inspect I think!

 

Go OEM for the water pump as well. It's not very expensive. It's the labor cost that makes a water pump job expensive. Also keep in mind that the water pump is smack dab in the middle of the most critical components of the engine. A bad install or part can ruin the entire motor.

 

Replacing or just testing the thermostat is much easier than replacing the water pump. The thermostat is mounted onto the front of the engine with three 10mm headed bolts. The lower radiator hose connects to the thermostat. After removing the clamp and sliding off the hose you just need to remove those 3 bolts. The bolt behind the tensioner rod is hard to reach if you don't have a 10mm wrench with a swinging head. The thermostat is mounted to the engine block with a gasket.

 

Wouldn't the water pump leak if it was bad?

OK if I am standing in front of the car facing the windshield I assume the hose you're talking about is the upper hose on the right hand side (driver side?) Follow that hose to where it connects to the engine right?

Do you think a novice can replace the Thermostat? Sorry for the silly question. It seems fairly straight forward but...

 

Opposite. It is the LOWER hose connected to the RAD. Its on the left standing in front of the max. The thermostat is mounted onto the front engine block on the far end of that hose.

 

The water pump only leaks if the o-rings are bad. If the impeller is bad, you'll just get a lack of flow.

 

Yes, but as Asand1 pointed out, and CS_AR pictured, this is more and more likely a case of the water pump being destroyed rather than going bad through normal wear and tear. As you may be beginning to see, frozen H20 is like the incredible hulk

No jacking up required. Pop the hood and follow the bottom radiator hose from the radiator to the engine block. The thermostat is right in there where the hose attaches to the engine. Follow the instructions from what jholley said.

 

I should have looked up the location 1st before posting my last post.
Anyway OK I pulled that hose off Sunday so I know exactly where it is. It should be fairly easy.

That nasty/aweful noise I was speaking of was a loud grinding noise. It made that noise a few times until I killed battery. Then I jumped and it went away.

I'll do the Stat today and hope but I'm with you... sounds like the water pump.

 

Cover the alternator before removing the thermostat. I little mixture will drip out.

If you don't have the tools to reach the bolt behind the tensioner rod then you might have to remove that rod. If needed then use this thread for guidance on removing then reassembling the idler pulley & tensioner rod setup.

https://maxima.org/forums/4th-genera...-assembly.html

 

Out of my league.
I'm gonna get someone to put it in. It seems fairly easy but I can't get to those bolts - talk about a tough spot. I'll keep you posted.
Thanks everyone for the help.

 

The thermostat was replaced already but yes I would test it to ensure it's opening and then pull the W/P....

 

OK I found a mechanic that came over tonight and installed the Thermostat. I could tell he knew what he was doing because his insight jived with what you buys have ben saying. Unfortunately it didn't do the trick. He agreed that it is almost a guarantee it's the water pump and he agreed that the WP install must be done correctly or there could be issues.

He's going to let me know if he can do the job. The WP install is waaay out of my league.

I'll keep you posted on the Water Pump.

 

Have the mechanic save the oem water pump so you can post pictures of it on this thread. If you ran tap water via your cooling system chances are the water pump impeller blades corroded and match the one CS has in post #56.

 

Yeah I saw that pic - nasty.

Does the oil have to be drained when the Water Pump is replaced?

 

No. Only the coolant needs draining.

Water Pump Replacement

 

Right from the link you posted: "Loosening the water pump coolant drain bolt minimizes the spillage but it is still pretty significant. You will need to drain and refill the oil at this point because of this."

So yes, drain the oil and keep the plug out while you're pulling the pump.

 

 

Ok guys it was the WATER PUMP! Everything works now.... no overheating, hot heat, radiator burped properly, etc... When he took the water pump out, the body (big piece) came out but the fins were left behind, hence the reason why it's in 2 pieces.


I think this happened because the night before the problem arose (couple weeks ago) it was the coldest night of the season. I think water froze in that area. I think that would explain the loud grinding noise I heard when turning the car over.


If anyone can post the pic so you don't have to click on a link please do.


http://web.mail.comcast.net/service/...=434333&part=2

 

http://web.mail.comcast.net/service/...=434334&part=2

 

Glad you got it fixed. Is it too earl to say told yah so ;-)

I get http error 404 when following the link. Start a photobucket account and posy the img link.

Sent from my XT1060 using Maxima

 

Try post #78. That link should open up.


I had a feeling a while back it was (based on the comments, symptoms, your comments, etc...) but the water pump was the most expensive and time consuming fix of them all.


I've gotten to know the 4th Gen fairly well and when something happens Sometimes I have an idea. Then I come on the ORG, read up, and figure it out (well you guys figure it out.)


Between both Max's I drove about 240k miles and never had a water pump issue so this was new to me.


I really don't know what I would do without you guys. Well I do know... I would spend a lot of money trying to get the car "fixed" by mechanics. LOL