NP300 YD25

Pauld · Postby **Pauld** » October 18th, 2016, 8:11 pm

Looking for some advice ,NP300 YD25 on morning start engine makes a loud knocking sound accompanied by white smoke .
as soon as the engine warms up to the mid temp on the gauge the sound goes away.
Massy keeps telling me its the quality of the diesel ,but I have owned a navara before with the same yd25 engine and never had this issue.
they keep doing fuel purges every time I carry it in ,but it makes no difference .

looking for some advice

Thanks
Paul.

FullStop · Postby **FullStop** » October 19th, 2016, 8:10 am

You're experiencing the situation where unburnt fuel is exiting the exhaust, that's the cause of the white smoke.
This is usually caused by deposits/buildup around the rings but can also be caused by failing glow plugs. You need to get this tended to immediately if the vehicle is under warranty.

FullStop · Postby **FullStop** » October 19th, 2016, 8:25 am

oh, sorry, just realized you also said loud knocking, so the the injectors can also be leaking...basically, you have the situation where there is fuel in your cylinder that isn't burning till the vehicle is up to temperature.

ADONI · Postby **ADONI** » October 21st, 2016, 11:37 am

That is Massy favourite excuse. If you get a flat tyre, the go tell you is the quality of diesel cause the tyre to go down...

BUSHMASTER · Postby **BUSHMASTER** » October 21st, 2016, 2:36 pm

ADONI wrote:That is Massy favourite excuse. If you get a flat tyre, the go tell you is the quality of diesel cause the tyre to go down...

car · Postby **car** » October 21st, 2016, 2:55 pm

If the knocking sound is coming from the front of the engine it could be the timing chain. Those yd25 engine always have those issuse but only when it crosses 100k. What's the milage?

Sude22 · Postby **Sude22** » November 17th, 2017, 8:18 pm

Hi good day i have an np300 Navarra VL model 2015 year when I starting on mornings I am, here a knocking sound coming from the engine.
When the engine heats up its stops and when gets cold again it start to knocks.
Anyone have n same problems.?.

car · Postby **car** » November 17th, 2017, 8:21 pm

Sude22 wrote:Hi good day i have an np300 Navarra VL model 2015 year when I starting on mornings I am, here a knocking sound coming from the engine.
When the engine heats up its stops and when gets cold again it start to knocks.
Anyone have n same problems.?.

Hydraulic tensioners on the timing chain. Either the chain stretch or the chain guides worn.
When you start most components are dry of oil. When oil get flowing it will cease. Common problem with these engines.