Please Advice On Replacing Engine Head/engine Of Nissan N16

vajz · July 4, 2013

Hi,

Please advice me on what should I do when I came across 2 times in changing gasket (I have nissan N16 super saloon, YOM - 2000, 1.6L) either to go for a new Engine HEAD or New Engine?

1st Occasion

- My careless driving (I never came across such a situation and didn't know what to do..but i was checking regularly the water level of over flow tank and the radiator)

- No cracks found in Engine Head and did not pace the head surface (after checking from a leading workshop which is located at Maradana)

- Replaced the gasket with a genuine nissan one.

- There were no any leaks found and however cleaned the radiator to make sure there are no longer any blocks (whether existed or not).

- Replaced thermostat valve with a genuine one, because there were no clue that the old one was functioning properly.

- Replaced Radiator Cap with a genuine one because there were some scratches at the rubber cap of old one.

- All of the mechanical part done by a experienced mechanic.

2nd Occasion

- Regularly monitored the engine heat level while driving and checking the water levels of radiator and over flow tank in daily basis.

- Replaced thermostat valve with a genuine one, it is not opening the valve at the correct temperature. (replaced with a genuine one)

- Replaced sensor which brings the temperature level of engine to indicate at the dash board temperature meter. (replaced with a genuine one)

- Both occasions,

- No any leaks found (Radiator and hoses)

- Replaced genuine thermostat valve. (both occasions)

Now i'm in the 2nd occasion and according to the mechanic (the Nissan agent in Sri Lanka which located at peliyagoda),they said, after proper scanning and testing this time also found that there is a issue pertaining to the gasket or engine head.

First occasion occurred in last December and again it happens now. Feel that if I fix the thing with existing engine / engine head from the agent it will cost me a lot because their labor charge is very high and if the thing happen again there is no point.

Please advise me what to do next?

maheshw · July 4, 2013

is this a automatic one or a manual gears one? if it's indicating a gasket issue, did you notice any white smoke from silencer? once you open the radiator cap are there any air bubles coming out ? if you have not used coolent check the water transparency again ?

i have heard that there is an link with the engine head cracks & gasket. be aware on what mechanics state on everytime changing this & that things.

will see how others comment on this.

vajz · July 4, 2013

On 7/4/2013 at 7:29 AM, maheshw said:
is this a automatic one or a manual gears one? if it's indicating a gasket issue, did you notice any white smoke from silencer? once you open the radiator cap are there any air bubles coming out ? if you have not used coolent check the water transparency again ?
i have heard that there is an link with the engine head cracks & gasket. be aware on what mechanics state on everytime changing this & that things.

will see how others comment on this.

Well this is a automatic one. every time used the coolant (except for one week after the first fix). At fist time it was indicated as an engine knock and less pulling power and that was the time I realized something went wrong. At first time did not notice any white smoke thing but oily air bubbles coming up when open the radiator cap at start mode. At the 2nd time initially identified as the thermostat is not properly functioning and later identified the heat sensor also not functioning.

Rumesh88 · July 4, 2013

On 7/4/2013 at 8:48 AM, vajz said:
Well this is a automatic one. every time used the coolant (except for one week after the first fix). At fist time it was indicated as an engine knock and less pulling power and that was the time I realized something went wrong. At first time did not notice any white smoke thing but oily air bubbles coming up when open the radiator cap at start mode. At the 2nd time initially identified as the thermostat is not properly functioning and later identified the heat sensor also not functioning.

What were the symptoms 2nd time? Was the engine actually overheating? It is very unlikely to have the thermostat and the heat sensor both getting busted at the same time for they are very reliable components. Did they face the head before replacing the gasket first time?

vajz · July 4, 2013

On 7/4/2013 at 9:08 AM, Rumesh88 said:
What were the symptoms 2nd time? Was the engine actually overheating? It is very unlikely to have the thermostat and the heat sensor both getting busted at the same time for they are very reliable components. Did they face the head before replacing the gasket first time?

Nope. did not face.

At the second time all of a sudden after riding 4 - 5km again felt something like knocking when gets slow (when is not accelerating). at the same time heat meter also moved towards upward from the middle position. So stopped the car and let the radiator to get cool and luckily there was a garage near by that area. After test ride and all it was identified as the issue with thermostat valve. So unplug the valve and again had a test run. While having the the test run something happened funny which was heat meter went up and down like nothing and finally figured out that sensor's jack also broken.

Rumesh88 · July 4, 2013

Looks like you either have a warped head or a hairline fracture in the head. If it is the former you may get away with the head faced and gasket replaced. But if it is the latter you would have to replace your head or find yourself a replacement engine.

maheshw · July 4, 2013

On 7/4/2013 at 9:58 AM, Rumesh88 said:
Looks like you either have a warped head or a hairline fracture in the head. If it is the former you may get away with the head faced and gasket replaced. But if it is the latter you would have to replace your head or find yourself a replacement engine.

well what about removing & re fixing all the identyfied sensors & other things? recheck all & let the engine run with a/c on idling for some time like one hour & notice.it's very bad to hear the same faults come on first trial.

The Don · July 7, 2013

You can normally check the functionality of a thermostatic valve and sensor by using a water heater, thermostat and a multi meter and probably a 12V feed. The thermostatic valve opens at a predefined temperature and the the voltage of the sensor varies according to temperature.