ethayng

Just bought a black '97 that runs great until the temp spikes.
I'm not driving it to avoid damaging the block/heads/HG.

Don't know much about this car. Had it for 4 days.
I know the previous owner wasn't much for maintenance... The rad and all reachable coolant lines were covered in calcium build-up probably from lots of fills with the garden hose. The engine has weird, small remnants of bad DIY maintenance (i.e batt fastener is missing lol).

Car info:
- 1997 Nissan Maxima GLE
- ODO reads 328k miles
- VQ30DE engine.
- Engine was replaced (don't know when or what the mileage is).
- Too many unknowns...

What I've done:
- Pulled the rad and all hoses out and flushed them individually (it was BAD).
- Put it back together, bought a flush kit, and back flushed it with the hose for 30min or so. Didn't use special fluids -- just water.
- Drained the rad and engine overnight.

What I am going to do:
- Back flush again with water and cleaner then drain.
- Fill with coolant and burp.
- Chem test for blown HG.

Symptoms:
- Lots 'O pressure (res overflow after a few min)
- Overheating after a few minutes idle.
- Water flew out the rad (no cap) during back flush when I gave it gas. HG leak or water pump?

What I do know:
- The thermostat works (took it out and boiled it).
- Everything else seems to be working fine (small upkeep needed, but nothing broken)

What I don't know:
- If my symptoms were caused by air bubbles that will be gone when I burp the system.
- If the fans work (haven't checked since I dumped the old coolant).
- If my HG is blown or engine is warped (haven't chem tested yet).
- If my water pump is dead. No clue how to test it.
- What to test if it still overheats when it's full of coolant

Where I'm at now:
Going to AAP after work to buy AT fluid (leaked a bit when removing rad) and cooling system cleaner for my thorough back flush. Back flushing and filling with coolant today. Hopefully I burp the system right and it doesn't overheat while I'm trying to do so.

I'll watch this thread for replies. I'm a dead poor HS grad and I'm willing to do the HG replacement / block grinding myself (I have the tools).

Reply with any questions. Thanks a ton in advance.

PH98I30

Is there water mixed in with the oil?... Milkshake color? Won't know much until you test the HG. Chem test and leak down test. I would do that first before wasting time on other stuff.

CS_AR

+1.

I use distilled water for flushing. That's all it takes.

JvG

Check to see if the fans turn on once it heats up. If they dont, you have found at least part of your problem.

You mentioned "lots of fills with the garden hose"

Hmm..... someone who is super cheap about maintaininga car would do that if a car had a persistent leak. So I would check the water pump weep hole for signs of leakage, or leaks from the radiator core.

It's also possible that someone put a stop leak product like Blue Devil in there. It sometimes stops leaks, and might be more effective as a radiator blocker.

Lastly, it is possible that you have a blown head gasket.

I would:

Check to see if fans come on
Look at the water pump weep hole
Remember if the radiator had big stains on it, from water leaks.
Do a block test with the head gasket checker and the blue testing fluid.

If the block test shows that the head gasket is ok, the car might be worth a new radiator. Because the old one probably is at least partry blocked, and leaks.

Old 4th gen Maximas don't cost all that much for a good one. Buy the best you can afford. It's cheaper in the long run. Less hassle as well.

ethayng

My oil looks fine as far as I'm aware. Not nearly like the stuff I've seen online -- old maybe, but not milky whatsoever.

ethayng

Duly noted. I didn't see any signs of bad leakage and it didn't seem to be leaking when I was running it before, but I'll def check again.
I haven't done anything with the water pump, but that's on my list.
Block test is on my list too.

Thanks for the quick replies.

JvG

The water pump on these cars is driven by the timing chain. Replacing it is not easy.

Replace only if it shows signs of leaking.
I'd check the fans and the radiator first.

Good luck, best wishes.

ethayng

Just checked. Fans work fine.

May be a thermostat problem... MASSIVE air bubble or clogged heater core.
Temp gauge not rising anymore (used to, now it's pinned to cool). Could be an air bubble... right?

Suggestions?

ethayng

Hoses going to the heater core don't seem to be the same temp and the cabin heat is VERY low... Checking the core now.

JvG

The air bubble you mentioned can cause overheating. Raise the front of the car on ramps or jacks at least 1 foot. Remove radiator cap. Idle car for at least 20 min. Blip throttle from time to time.

ethayng

I did that... it didn't seem to work. Got a pretty constant stream of bubbles (especially when the WATER STARTED BOILING (dist water & cleaner))!!

That's a *bad* sign right?

ethayng

Symptoms are adding up to be a HG problem... Biggest one is air in the rad that increases with RPMs. Tried burping -- seemingly infinite supply of air in the hoses. Thermostat didn't seem to be opening, but that could have been because of the air being pumped into the system.

Just going to buy a kit and do it myself. I have the time and not the money. Going to get the heads ground down at a shop, possibly replace other internals as well. Going to be expensive, but should be worth it in the long run.

Any suggestions?

JvG

Did your fans turn on whole you idled the car?

If they did, they behaved normally.

If not, that is at least part of your problem.

It would be normal for the car to boil over at idle, with no working fans, while the radiator cap is off.

JvG

I'd do a block check myself before I did anything else. If it passes, replacing the radiator would go a long way towards solving the problem.

The heads take more time and money to remove than it would take to install another engine.

Considering that your car has over 300k on it so far, you might want to think for a while about what might be best.

We don't win them all.

ethayng

The fans turned on quickly yes. I was idling the whole time.

I get that it gets hot and pressurized, but the pressure was directly linked to the throttle... I don't think it's the pump... Am I wrong? Doing a chem test tomorrow to check for emissions.

ethayng

I can do that. I should probably get a new rad anyway

I would do it myself. Total cost would be about $350 (I would take the heads to get machined and replace the HGs and timing chain).
Right... The engine was already replaced once -- you're right though, and I have no idea how many miles are on this thing.

Gah.. So true. Honestly, even the expensive route would be cheaper for me than buying a cheap used car. Like, thousands cheaper. I got this one for $850 and am willing to put the time in for repairs...

JvG

Perhaps you are thinking about what it was like to remove the heads from a Chevy 350 or something.

I've done a couple of Chrysler 318 engines myself.

The engine in th maxima is overhead cam, and is driven by the timing chain and cam chains. Removing the heads on these looks to be a whole lot more involved than the engines of old.

I do not recall many of our members replacing their own heads. I have been following this forum for over ten years.

The previous owner could have replaced the radiator long ago for between 50 and 100 bucks.
But he chose not to. He burned up one engine, and replaced it. The old radiator might have done in this engine as well.

All because the owner was too cheap to replace the radiator.

Here in town I see good maximas for less than 2k for a good one, and 500 and up for a bad one.

The 1500 dollar price difference avoids a lot of grief.

A cheap Maxima can be quite expensive.

ethayng

It would be an involved project, and would be very tedious work... Hell, I could even screw the whole thing up for good.

My thought is, I can gamble with an engine swap and fork over labor costs for that, I could pay to get the HG replaced (at which point I might as well replace the engine), or I could pay $300 and try to do it myself... Which could turn out just fine in the end.

I'm clueless. Going with the third, cheapest option seems good to me at the moment.

CS_AR

Parts of this thread reminds me of an adventure with my 3rd 4th gen.

Previous owner was too cheap to fix a leaking radiator so they filled it with some kind of stop leak and sold the car to me. The car must have run hot several times before they decided to sell it. They were letting a Buick dealer do all of the work.

If you really have a blown head gasket, you might find scored cylinders along with it. In that case, the engine has been trashed.

How do I know this? Here's some pictures below. Also, the overheating seemed to shorten the life of injector-o-rings that lead to excessive flooding and clogged cats.

Hopefully, you won't experience an extreme case like I did with the 99 model in the winter of 2014.






Scored cylinder walls on an engine with approximately 160,000 miles.





I bought an engine from a wrecked Maxima in the picture below with 82,000 miles for $500 (the yard pulled the engine as part of the deal) and paid another $1,500 for installation and some other item installation like seals and water pump. And that was for starters. The only reason I kept dumping money into that 99 model is because it is a SE 5-MT. Those are rare vehicles in my area.

ethayng

Hm... Did you have smoke in your exhaust? My exhaust seems normal to me... Completely clear.

Is there a way I could check for the cylinder damage WITHOUT having to take the heads off? Wouldn't oil be leaking into the fuel line?

Thanks for the info and the FANTASTIC pics.

JvG

Oil will not leak into a fuel line.

First, do a block test to determine if your head gaskets are ok. If that passes, remove all your spark plugs and do a compression test.
Unless the engine passes both tests , plan on replacing the engine, or the whole car.

CS_AR

We need to answer JVG's questions.

ethayng

I'll be doing the block test this afternoon. I'll post results here. I can rent a compression tester from AAP and get that done as well, but maybe not today...

I LOVE the car... Unless I can find one that I like better for 2k, I'd replace the engine, and I won't be able to do that any time soon. I'm poor af.

JvG

I understand that money is an issue.
I've been there myself.

I've learned to do a great many things over the years due to economic reasons.

That said, Im curious how much experience you have had working on cars, your age, and also which and how many tools you have.

Have you actually removed heads from engines, or replaced an engine in a front wheel drive car?

Also, keep in mind, while you might be able to find a good engine for 300 dollars, it would be wise to replace some items on that engine before you install it.

This engine has a water pump which is a real pita to replace while it is in the car. It would be much easier to work on before it is installed.

The valve cover gaskets like to leak. Replace those as well.

The rear main seal should be replaced of course. Because it is easy out of the car, but would require transmission removal if it's in the car. The front crank seal should be replaced as well

So plan on 200 to 300 extra dollars.

Your car has many miles on it, even for a Maxima.
Unless your engine is still good, or you are a glutton for punishment, you might want to walk away from this car. Find one with more manageable issues. Even if you need to finance it.

ethayng

I have little experience, with heavy car maintenance, ever so slightly above average knowledge on cars, and I have the tools (socket set, screwdrivers, mallet, torque-wrench, and an AAP that rents tools I could need).
I'm willing to learn though, and there's always a first time

Hm... I'll definitely look into getting a new engine.. Today actually. I'm visiting a local junk yard that may have a few wrecks I can part from. I'll ask about a VQ30 (or whatever the 3.5l one is that you all keep raging about).

I'm ball-parking, but I would assume that the current engine doesn't have more than 150k - 200k miles on it (which is a lot, but it's low enough).

I'd buy a full kit and replace every gasket/seal I see.

JvG

While others might say to get the 3.5, you might want to keep things as simple and as inexpensive as possible. Ingeneral, the 3.0 does not burn oul, while many of the 3.5s do. Then there is the matter of the computer and such. It's set for the 3.0.

PH98I30

Stick with the 3.0L. It is an award winning engine. It will run to 300,000 miles or more when maintained.

ethayng

I'm not sure I'll even need a new engine.

I ran a block test yesterday and it passed... I'm glad. Confused, but glad.

I filled it with coolant and will finish burping the system this afternoon.
I couldn't finish burping the system because the coolant was boiling -- probably due to the ton of trans fluid I dumped when I cleaned the rad. It's an auto trans so it's likely dumping extra heat into the rad.
I'm filling up the trans fluid, burping, then running the block test again just for good measure.

Oh and my heater gauge wasn't working. Had to fix the single wire going to the ECTS at the spot where the upper rad hose connects to the engine. All's well that ends well.

I'll make sure to post results.

PH98I30

You should get a new radiator. They can be had for $100 or less. The one you have sounds abused. If the thermostat is good, then I would look at the water pump. If its not leaking, I wonder if your cooling fins are corroded. The timing chain runs the water pump.

ethayng

I'm thinking the same thing. My budget is SO tight rn, but I'll get a new one ASAP -- even if it's not the main problem. It's a bit.... *aged*...

JvG

What color was the auto trans fluid?

Should be salmon pink to darkish red. Should smell similar to new fluid. If it smells burnt, and the color is brown through black, your transmission will not live much longer.

The reason o bring this up is that the transmission is cooled by a good radiator, or boiled and cooked to death by a bad one.

You have done a block test. Before spending any more money, do a compression test, and shoe us your spark plugs. You want even compression between cylinders. An over heated engine can score cylinder walls, like CS-AR mentioned. It can also affect piston rings.

If compression is bad, you will need a replacement engine. If it is good, you probably have a good engine. The heat might have messed up your injector seals. Don't worry about that now, but keep it in mind .

Radiators are 50 to 100 bucks online. I bought the koyorad for mine. I was impressed by the quality.

Don't mean to be Debbie Downer, but unless the trans fluid was not burnt, and until the compression test has been done, hang on to your savings.

However, if it passes the tests, buy a radiator asap, and enjoy your car.

ethayng

Trans fluid was fine when it was at normal levels
Haven't checked it, haven't been running it hot enough to burn it.

*sigh*.. I'll do a compression test and post the results here (hopefully today).

JvG

What color was the trans fluid?

Probably more important than fluid level.

Overheating causes transmission failure. First the fluid changes color, later on the trans dies.

Is it red, brown, or black?

ethayng

Red. Just filled it up today too.

krismax

iTrader: (15)

Replacing the engine by yourself is far cheaper and less time consuming.And the risk you run is far less .

I just bought an 2001 infiniti I30 engine with 40,000 miles on it, with a 1 year warranty for $1000.

You can get an engine for $100-$300 for 95-99 maxima's all day long.

ethayng

I'll keep that in mind...

ethayng

Ok guys. Compression test results for ya.

Pistons numbered as labeled in the manual:

Back
|135|
|246|
Front

1 ~ 180
2 ~ 177
3 ~ 170
4 ~ 155 *
5 ~ 180
6 ~ 150 *

4 and 6 are low. They're both in the front head, take that as you will.

All seems well with the test. I'll keep my eye on 4 and 6...

CS_AR

Just for curiosity, what brand and type of spark plugs are you running?

ethayng

UPDATE:
The car seems to be running fine now. The fans started working properly once the MAS was unplugged (more on that in a minute). I bought a new thermostat which seemed to fix a large part of the issue, and I BURPED THE SYSTEM. Emphasis on that last part -- I was overheating until I gave it a good long idle full of coolant on jacks (Rad cap on. Don't be stupid.)

We'll see how things work out when I can get past 2k RPM again

MAS (mass airflow sensor) broke. New one is coming in the mail. I'll be able to throttle over 2k RPM when it comes lol
It was throwing errors before it broke. It broke when I was opening it to clean the sensor.

Radiator has a leak around the top where the core joins the housing ONLY WHEN COLD. When the pressure builds inside the rad, the leak seals itself. I'll be buying a new rad ASAP.

Other misc parts of the car need to be fixed... Pinhole braking fluid leak somewhere, AC completely depressurized, tons of old gaskets here and there, needs an oil change, etc.

To sum up:
Big problem was the thermostat. Cooling lines were gunked up, installed a back flush system ($4 plastic T that goes on your hose) and flushed it good. Radiator cap replaced so it could maintain pressure correctly. Cleaned the spark plugs and made sure their gap size was good (~0.42). Compression test was essential and free (rented the tools and did it myself). Refilled the coolant (50/50) and removed ALL THE AIR. It took a while to get it all out because I emptied the coolant to clean the rad.

Everything is good so far. I'll post if I run into cooling problems again.

JvG

​​​​​​
The air is coming in from the leak in the radiator.

The compression numbers look good, and within specs.

You have lower compression between two adjacent cylinders in front, with similar compression readings. This could be valves which need adjustment, random chance, or a slight head gasket leak.

One thing I'm concerned about. The cooling lines were gunked up. Also the thermostat was gunk ed up. There was gunk in the radiator too.

Is the gunk the same substance? Same color?

I'm still thinking stop leak. I hope it was there to fix the radiator, not the head gasket.

All in all though, this is encouraging.

Naturally, you should fix the brakes asap.

Do you live in an area where road salt is used?