Weird sound from exhaust(RB20DE NEO)

[Kapr]

Little bit late "2days" but i saw the engine.
Mechanic will send the head to "machine" shop for testing but after a long inspection himself he do not see any damage on head/valves or whole cylinder head(no cracks or anything like that)...even head gasket is ok.
Block and piston(s) are in great condition and he was very suprised how the engine looked(very clean/undamaged) (engine has 210k Km)

So after my Q WTF is wrong then...he thinks one of the valves do not close properly...He still need to look at the camshafts and everything "above" but it seem this "could" be something minor...

On the other hand...one part gone wrong kinda bad 😄
https://jp-carparts.com/nissan/partlist.php?maker=nissan&type=81&fig=140A&part=14510AA000&page=2
This part(as seen on photos) gone bad....the whole section where water comes in is destroyed..."corroded" away...

So here is the question on that part...it seems that from factory there was "metal" pipe stuck into the housing and THAT "melt" away?
Or does anyone know if it is how we think it is? Cuz everything around is ok...only that "something" corroded away completely.
We will try to weld some pipe if we can...cuz this part alone costs around 1200 USD and that is before taxes/shipping...and god know if they even had this in stock and in the reasonable time.

 

[Hendry]

I replaced that metal pipe in RB25det manifold so I think it can also be replaced in your manifold. I ordered new pipe from machineshop according to measures and installed it to manifold with rtv.

[Kapr]

@Hendry: i hope we can too but on RB25DE/T this part is different ...in RB20DE NEO it "splits" into two parts...on others the manifold is one part...and that "corroed" part looks different too.
But i saw some pictures of it and it looks like there was some metal pipe too...

This picture is from RB25DET NEO and looks little bit different but yeah...100% metal pipe...mine is/was the same it should be easy to repair 🙂 

And this is part from RB20DE NEO...metal pipe too 🙂 

On the other hand my mechanic discovers that on 99,9% problem is exhaust valve on cyl 5. (both of them)
They leaking fluid...but the head is OK so tomorrow we send it to a machine shop to check if the valves could be machined or if we need to order some new ones.

But so far it is looking "good" 🙂 

Edited March 14, 2022 by Kapr

[GoHashiriya]

Are you okay getting parts from Japan at the moment? My local post office won't let me send anything to the UK currently due to the Ukraine situation. DHL, etc seem to be okay but the prices are well.. unenticing. 

[Kapr]

On 22/03/2022 at 9:55 AM, GoHashiriya said:

Are you okay getting parts from Japan at the moment? My local post office won't let me send anything to the UK currently due to the Ukraine situation. DHL, etc seem to be okay but the prices are well.. unenticing. 

Sorry for later reply. 
Yeah i ordered many things from Japan(JP Parts) and some from Dubai and everything was ok...
JP Parts are EXTREMELY quick...like 4 days from payment i got my stuff...yeah they are little bit expensive but i dont mind...iam happy that they have the parts 🙂 

But yeah iam using DHL...our local post office sucks hard 😄 

[Neostead2000]

It looks like those are very common problems on these NEOs. My water pipe sleeve was also moderately corroded but I can still keep using it. You can just pull it out and have a standard sleeve with a lip machined, or just look for any pipe you have laying around that would be a snug fit, but certainly would need to have a lip at the end so the hose can seal well.

Also when i took apart my RB20 Neo I also noticed ALL of the exhaust valves and their seats were very pitted, whereas the intake valves looked spotless. This is a very low mileage motor, mind you (I am guessing less than 60k km). I ended up lapping all the valves and polishing the chambers to give it more flow since I will be turbocharging.

Also, can you link exactly which JP parts store website you are referencing? I want to avoid Amayama also as I just saw they have 60-90 day delivery times which is insane. I am almost ready to assemble my engine, I will be updating my build journal with it so keep an eye out if you want to see more about the 20 Neo

[BK]

Jp car parts, they are excellent.

https://jp-carparts.com/