Injector nozzle for diesel engines is very important for the engine performance, especially the holes on the tip and the seating. But it is not easy to inspect them due to its small sizes.
Here we tried to use our current digital microscopes and borescopes to see what we can see.
Here we tried to use our current digital microscopes and borescopes to see what we can see.
1. Microscope inspection from the outside of the injector nozzle.
Microscope used: ViTiny UM10.
Injector Nozzle model: DLLA 146P1581
Injector Nozzle model: DLLA 146P1581
2. Inspection of the holes by pen-type microscopes.
The injector nozzle has very small opening at the top. The inner diameter is less than 4mm. Most of microscopes can not see into the deep side of the hole, because there is no light can be shed inside.
We have one small diameter pen-type USB microscope, model PM-40. PM-40 has a diameter of 3.9mm camera, and is equipped with 4 LED lights at the front of the probe. PM-40 can be focused manually to see close and far. We found that only PM-40 can see into the hole of this injector nozzle.
The injector nozzle has very small opening at the top. The inner diameter is less than 4mm. Most of microscopes can not see into the deep side of the hole, because there is no light can be shed inside.
We have one small diameter pen-type USB microscope, model PM-40. PM-40 has a diameter of 3.9mm camera, and is equipped with 4 LED lights at the front of the probe. PM-40 can be focused manually to see close and far. We found that only PM-40 can see into the hole of this injector nozzle.
Microscopic view from the top of the nozzle hole
3. Looking inside the injector nozzle with small diameter video borescopes or fiberscopes.
The opening of the injector nozzle is less than 4mm. One nozzle sample has inner diameter about 3.5mm and another one about 3.9mm. And the opening goes narrower as it goes deep into the tip side.
To see inside the nozzle, we has to use a borescope with diameter less than 3.9mm, or even smaller than 3mm.
The opening of the injector nozzle is less than 4mm. One nozzle sample has inner diameter about 3.5mm and another one about 3.9mm. And the opening goes narrower as it goes deep into the tip side.
To see inside the nozzle, we has to use a borescope with diameter less than 3.9mm, or even smaller than 3mm.
Observations and learnings:
- 3.8mm diameter borescope can see inside of nozzle, but only can go inside a little bit deep.
- 2.8mm, 2.7mm and 2mm diameter borescopes / fiberscopes can go deeper to see full range of the nozzle.
- Large diameter video borescopes and fiberscopes give better quality images and views.
Suitable borescopes and fiberscopes to look inside diesel injector nozzles:
- VC-2810, with 2.8mm diameter camera.
- NP-2011 video borescope, with 2mm camera
- RC-215 rigid borescope with 2mm camera
- VC-2010 video borescope, with 2mm probe camera
- VC-3810 borescope with 3.8mm diameter. Only can be used for some large nozzles. And limited accessibility