2003 Nissan Patrol GUIII 3Ltr TD - cooling system problem

Dear Girlpower

Oh dear! I think the RAC could have been more helpful, as I'm sure you would have paid a significant amount for the check.
I am no mechanic, but can relate some of my similar experiences. I'm sure you will get some informed replies from others.

1. The problem is, as you have been told, possibly due to cracks in the head, and/or head gasket, hence big. Be absolutely sure, however, that there are no tiny hose or fitting leaks which only show under pressure and which may appear only as small residue deposits from evaporated coolant. This probably unlikely as the RAC should have looked for this.

2. I've had head/gasket leaks fixed on two occasions with additive to the coolant - once in a Fergy 35 and recently in a 63 EH Holden. The name of the product eludes me, but my mechanic of 30 years, very reputable, said the stuff we put in the EH is used still in Commodores by Holden dealers. They are brown discs about 20mm diameter which are crumbled and dropped in the radiator. You should seek expert advice before dropping it into the Nissan, I guess, being a diesel, but I can't see that it could hurt.

3. I would think it should be fixed.

4. I guess Chemiweld is similar to what I used.

5. It must be saleable, it's just your conscience... Unload it on a dealer.

Regards, John.

Hi Girlpower - Not with the Patrol, but with a Landcruiser we had what was suspected to be a hairline fracture. Cruiser started to overheat and loose only a bit of water. Mechanic put in a couple of bottles of a sealant stuff, and it was fine from then on. Although it had no more problems, we did eventually trade it on a new Cruiser ute. Worth a try for you to use the Chemiweld or whatever.

Motherhen

I would be inclined to use "Bars Leak" which will mix with most coolants. Previous experience with Chemiweld showed it to be ineffective whereapon Bars had fixed the problem. Chemiweld usually has to be drained from the system after it's initial use & you therefore have the expense of a complete refill of coolant. Bars Leak can be left in semi-permanantly or untill your next coolant change. I have no affiliation with Bars.

Hi GirlPower,

I recently had a similar problem on GU-111. The cooling system has three reservoirs 1) radiator, 2) pressurised expansion tank, and 3) refill tank. The latter two are on the LHS of engine bay. In my case there was a hairline crack on the hose outlet of the pressurised expansion volume. Pressure checking the radiator circuit did not find it, until they pressure checked the plastic expansion tank. Replaced and problem disappearred. The position of the hosetail outlet suggests to me that someone lent on it during a service, hence the damage.

I also had another coolant leak after Nissan repaired an exhaust leak. They had forgotten to tighten hose clamp to the turbo - it is engine coolant cooled. I imagine that a radiator pressure test would pick this up, plus you'd see signs of coolant on turbo heat shield.

Hope this helps.

Hugh

Try posting your question on the Patrol 4X4 website:
www.patrol4x4.com/forum/
You'll also get some advice on there as well

Rob

They do crack heads severely but I would be checking the things already mentioned previously as heads are expensive to replace. The bare head is reasonably priced new but its the labour to remove and replace plus to lap all the valves in and do all the clearances. Lots and lots of hours to work on these things.

Don't assume the worst....I went through this with my gu.....AND yes it was the plastic header tank had a crack which would only show up at high speed, so no pressure test would show it up. By the way it took me 50,000kms to find the problem. A few mechanics just wanted to pull the head off to have a look at $3000+ DO ALL POSSIBLE TESTS FIRST!!!

I would do things in this order

1.replace radiator cap with a QUALITY one...not super cheap and check all hoses and clamps
2. Get your radiator removed and inspected and cleaned by a pro
3. Get a leak down test done to see if any cylinders are showing cracks
4. There is a test where they check for combustion gas in the coolant (cant remember what it is called)
5 Put it on a dyno so you can see what is happening as the car is 'driving'

If all this does not show anything then use the bars stop leak and consider what you want to do. IE sell or fix

Cheers Stefan

P.S this problem is very familiar to me, if you want more info my e-mail is in my member page, would be only to happy to help as it nearly drove me crazy. As I said before it took me 2 years and nearly 50000km to finally find the issue in mine.

goodday
open the oil filler cap and check for CREAMINESS around it fi there is any creaminess then you definitely have a cracked head other wise go to all the steps above
creaminess means water in the oil
steve