OmegaSpeed

Burped it again this morning but this time without adding water. After about 20 minutes it kicked out a ton of bubbles. Ran it at idle for about 30 minutes until the second fan came on and it sucked most of the fluids back in. Shut the motor off, inserted the stopper, removed the funnel, and disposed of the excess water/coolant.

Did you codes go away right away or did it take a bunch of cold starts to clear them once you fixed the problem? And also I'm hearing conflicting information... Is it a good idea or a bad idea to squeeze the radiator hoses with the spill free funnel on while the motor is running and you're burping the system?

Neimad

FSM:

WARNING: To avoid being scalded, never change the coolant when the engine is hot.
Wrap a thick cloth around cap and carefully remove the cap. First, turn the cap a quarter of a turn to release built-up pressure. Then turn the cap all the way.
Be careful not to allow coolant to contact drive belts.

REFILLING ENGINE COOLANT


Install reservoir tank if removed, and radiator drain plug.
Close and tighten cylinder block drain plugs securely if removed.
Apply sealant to the threads of the cylinder block drain plugs.
Use Genuine RTV silicone sealant or equivalent.
Radiator drain plug:...........................0.78 -1.6 Nm (0.08 - 0.15 kgf-cm, 7 - 13 inch lbs.)
Cylinder block drain plug (LH):.........................17.6 - 21.6 Nm (1.8 - 2.2 kgf-cm, 13 - 15 ft. lbs.)
Cylinder block drain plug (RH):....................17.6 - 21.6 Nm (1.8 - 2.2 kgf-cm, 13 - 15 ft. lbs.)
Cylinder block drain plug (Front side):....................7.8 -11.8 Nm (0.8 -1.2 Kg-m, 69 -104 inch lbs.)









Remove air relief plug on heater hose.













Fill radiator and reservoir tank to specified level.
Pour coolant through coolant filler neck slowly of less than 2 L (2-1/8 US qt, 1-3/4 Imp qt) a minute to allow air in system to escape.
Use genuine Nissan anti-freeze coolant or equivalent mixed with water (distilled or demineralized.
Engine coolant capacity (with reservoir tank at MAX level):........Approximately..8.7 L (9-1/4 US qt. 7-5/8 Imp qt)
Reservoir tank capacity (at MAX level):.............0.8 L (7/8 US qt. 3/4 Imp qt)

When coolant overflows air relief hole on heater hose, install air relief plug with new O-ring.
Air relief plug:.......................0.78 - 1.6 Nm (0.08 - 0.15 kgf-cm, 7 - 13 ft. lbs.)

If coolant does not overflow air relief hole, grasp upper radiator hose so that it occurs with closing radiator cap. After installing air relief plug, open radiator cap and fill radiator.
Warm up engine to normal operating temperature with radiator cap installed.
Run engine at 3,000 rpm for 10 seconds and return to idle speed. Repeat two or three times.
Stop engine and cool down to less than approximately 50°C (122°F) .
Cool down using a fan to reduce the time.
If necessary, refill radiator up to filler neck with coolant.
Refill reservoir tank to MAX level line with coolant.
Repeat steps 5 through 8 two or more times with radiator cap installed until coolant level no longer drops.
Check cooling system for leaks with engine running.
Warm up engine, and check for sound of coolant flow while running engine from idle up to 3,000 rpm with heater temperature controller set at several position between COOL and WARM. Sound may be noticeable at heater unit.
Repeat step 10 three times.
If sound is heard, bleed air from cooling system by repeating step 5 through 8 until coolant level no longer drops. Clean excess coolant from engine.

DaveJackson

iTrader: (5)

This is the critical step that all ignore & pay for after. That is a trickle of flow.

OmegaSpeed

Since the last post I only burped it once the day after without pouring in any fluids for about 30 minutes or so. The day after I didn't fill or burp. I put 60+ miles on it driving both stop n go and freeway traffic with the heater on. It didn't overheat and no sign of rising temperatures.

I'm burping it again now (no additional fluids) and after about 20 minutes I started getting bubbles. I'm missing my coolant reservior so that will be something I'll have to buy here soon. I notice when the second fan kicks it in pulls any fluid in the spill free funnel into the motor.

I left the heater bleeder screw off and after about 25 minutes coolant started coming out of it. Is that normal or just more air pockets pushing coolant up and out of that bleeder? I put the screw back on just enough so coolant wouldn't spill out for about 5-8 minutes then removed the screw again. No sign of coolant coming out now even through the second fan cycling on and off.

I'll continue to keep you all posted.

OmegaSpeed

Hit about 90 miles (since the last overheat) this morning and overheated again. It took a little less than a half gallon of water to fill. I'm burping it again now. I had bubbles coming up as quickly as 3 minutes in and coolant coming out of the heater bleeder again. Second fan came on 8 minutes in this time.

I took the advice of pouring at a trickle flow pace also. The oil isn't milky but I do have condensation burning in the exhaust.... Do you guys think it's just an air bubble problem? I don't see how I could have done anything to the head by shutting down the car so quickly (it never shut itself off). :/

Checkmate58

iTrader: (11)

Check water pump still. I had a bad thermostat and changed it out with an OEM one. Car ran fine for a few months. Then the car started overheating but a few days before, I started smelling burned coolant. No white smoke from exhaust. Changed my oil, nothing milky. Continued to drive the car and then I noticed that coolant was leaking. Checked all the hoses, everything was okay. Looked under the car and saw that it was coming from around the waterpump area. You need the reservoir. It'll give you an idea if coolant is being burned up or leaking slowly. I filled mine to the maximum level. It started to get lower and lower each day and that's when I realized that something wasn't right.

Ended up taking it to the dealership and they agreed with a bad waterpump. Changed it out and did the belts while I was at it. No problems since.

If its not the waterpump then I guess next steps would be check compression or leak-down test.

Neimad

I missed that bit about no reservoir, you are sucking air in from that line without it.

"The overflow tank serves no function in the normal operation of the coolant system. It only comes into play if there is an overpressurization and the rad cap opens, and then it only serves as a safe, environmentally responsible collection point for expelled coolant.

If the system pressure reaches the cap’s pressure rating, the cap’s spring is compressed, forcing the valve open and allowing coolant to escape through the overflow tube to the overflow tank. After such an event, as the system cools it contracts, creating vacuum that opens the other spring- loaded valve, in the rad cap, allowing coolant in the overflow tank to be sucked back into the radiator."

Really good tech: http://www.pirate4x4.com/tech/billavista/Cooling/

labelworkshop75

iTrader: (13)

^^^ Yea you are sucking in air.

OmegaSpeed

Sir, I believe you're right. The only thing that stumps me is the motor had 1600 miles without a reservoir??? I listed everything in a previous post but I've already changed the water pump housing, thermostat, and coolant temperature sensor. Not having a reservoir could definitely explain where the constant bubbles come from.

I'll keep you all posted.

Spike100

The Z’s overheating issue is so common there probably should be a sticky describing this problem and its fix.

--Spike

OmegaSpeed

Ok so I think I may finally be ok. I put 80 miles in one trip in the car and this morning the check engine light finally went away! I'm now drivin the heater on but at a low speed setting (just to be safe).

I did not replace the reservoir yet but I do believe I was sucking in air after it got too hot and the spring in the cap had to open and close (which may explain why I never had the problem before because it never got hot enough to have to open and suck in more coolant maybe).

What I did in my last post seemed to have worked... I poured in water at a TRICKLE pace. I also burped it for well over and hour until I couldn't seem to get any more bubbles out. This I did twice... Once I think for 30-40 minutes and then again for about an hour and 15. Also a key change I made was after filling the radiator to the top, I kept pouring in more water until the spill free funnel was about a third to halfway full allowing the system to suck in more fluid as it needed.

I hope it stays fixed. Thanks for all your help guys. I will add the reservoir in the near future also.