Nissan Patrol 4x4 (Africa)

When Sugar Honey Ice Tea hits the fan...... it really does hit the fan !!!!

We were driving from Maputo back home towards Alberton, when I noticed that my radiator had developed a small hole and was loosing water. So every 20 odd Km I stopped and filled up the radiator hoping to get closer to home. We were watching the temp guage like hawks, but the needle NEVER moved above half !!! Thinking that we are still safe temperature wise, we slowly made our way to Nelspruit. Again I filled up the radiator whle idling the engine..... put the cap on and switched the Patrol off.... went into the shop to buy a cooldrink.... came out started the Patrol and that was it...... water out the exhaust !!!!

So now tomorrow I am going to start stripping .... again .... First the radiator .... to figure out how a hole got on the inside of the radiator on the cores that run vertical.... and then the head to hopefully only replace headgasket.

How many times can a head be skimmed??.... I know I've skimmed mine once when I the motor blew a holle in the no 2 piston. The head has also had the ports polished by the previous owner, so thats 2 times that I know of and this will be the 3rd time if it is possible to do so. Being cast iron, would it even need to be skimmed? Is there a different or special head gasket that must be used that is slightly thicker to compensate for the additional skimming? Should I look at buying a new head or recon head?

I also notice that there is a little bit of oil that works its its way via the vent pipe return from the tapet cover to the turbo inlet. This oil works its way through the turbo and into the I/C. Is this normal???.... Its not a lot, but while the head is off.... I might aswell address this issue too if it is a problem.

The problem I had on my Patrol was that the cover on the radiator - on the inside - have 2 pins at the bottom and 2 screws on the top that secure the cover.

One of the pins at the bottom broke off and the cover started vibrating. There are two plastic studs on the inside of the cover that was touching/hitting the radiator becauce of the vibration.

I fixed the hole with Pratley Steel and curry powder and it was fine for months till I hit the cow in Botswana and had rhe radiator replaced.

I can't see the hole but can feel it. when looking at the your photo of the hole up close, and when I feel with my finger on my radiator.... this could be what caused the leak !!!.... I'll keep you posted when the radiator is out !!

Eish Cedrick, that's bad news.

The problem is that the temperature gauge needs to be in water to work and it is situated almost at the highest point of the whole cooling system, so if you are low on water, then the gauge doe'sn't work properly. Therefore never continue if you know you are losing water, rather take time out to try and repair the problem.

It is however possible that the head might not be warped, so check before you skim. It is also not a question of how many times it can be skimmed, but rather of how much metal has been removed in total. There should be a minimum figure in the manual for the thickness of the head. Fortunately on a pushrod engine like this, skimming the head doesn't change the valve timing, so the effects are limited to the possibility of the valves hitting the pistons, the possibility of exposing a water channel, and an increase in compression ratio.

I know that there are extra-thick head gaskets available for some engines, not sure how whether your 4.2 falls in that group and also not sure how well they work. A possible alternative is to have the pistons pocketed by the amount the head is undersize in order to avoid them touching? I am not sure whether this engine would be affected by the slight increase in compression ratio? I am sure Frans can give better input here.

Oil from the breather would be a result of worn rings/bores or glazed bores. Since your engine was re-done not long ago, I would have a good look for glazed bores. If that is the problem, just hone the bores again and change your running-in procedure. However this oil should not really be a problem except that it dirties the intercooler. You could look at changing the plumbing so that that oil is not re-introduced back into the engine. Just hang the pipe down low but make sure you put a filter on the end and never stop with it hanging in water, because as the engine cools it will suck whatever is at the end of this pipe into your engine.

Thinking back now.... when I did the rebuild... I noticed that the new head gasket was slightly bent possibly kinked with transporting. I recall I wasn't too concerned about it as I figured that the pressure of the head squeezing the gasket to the block would ....for want of a better word .... iron out that slight bend/kink. This was possibly a weak point and with the temp rising caused the head gasket to fail........ hmmm the thick plottens...

Cedric, you can also build and fit a simple catch can to keep the oily mist out of the inter-cooler - there are plenty of plans on the Oz Patrol forum.

That'll be one of my next projects...

I'll go hunt around and look into it...... so its a normal standard thing this oil vapour I take it.

Sorry to hear!!!fix it 3 provences are on its way!!!

ha ha...yes.... I hope all will be well by then....I'll use it as a run in period.

Just battling to find a head gasket thats oversized due to te head having been skimmed twice that I know of !!!.... any suggestions?????

Cedrick measure that head before you start running around looking for special gaskets?