Oil spray nozzle

[whizbyu]

My 2005 Passat TDI comes with oil spray nozzles. There are curved nozzles that are bolted in to the engine block and spray oil to the bottoms of pistons to help cool the piston when under heavy load. One of the nozzles broke off in mine, cylinder #4, likely from the previous owner damaging it while changing out a piston.
The only way to replace one is to take the motor out and disassemble the motor. Tried to do the repair with the oil pan off and it won't work.
It is a single passenger driver 90% of the time. Relatively flat roads. I do not tow, do not gun, and typically drive in a manner to get as many MPG as I can.
As I understand it, a Porsche 944 Turbe does not have any spray nozzles and I know of many 944 Turbo motors lasting way past 300,00o miles.
I suppose diesel motors generate less heat. Has anyone every had the same issue with broken nozzles?
Thanks

 

[maxdustington]

It's the .01 percent of the time where you have to pin it that is going to smoke the mill.
You can rationalize it, but that's probably an important engine component. Durability will be sacrificed on a 13 year old car. It is up to you how you feel about that.

 

[clinebarger]

Direct Injected Diesel pistons generally run hotter especially at max load as the combustion chamber is part of the piston.

 

[bullwinkle]

If your engine wasn't a turbo, it could likely survive not having it. Look at it this way-it's already had that piston replaced once, likely when the nozzle failed-odds are it'll burn a hole in that piston again without it.

 

[AVB]

That is a good point.

 

[DoubleWasp]

Piston design being the largest factor.

Some piston literally only get by because of cooling jets. The piston would need to be larger and heavier without them. Some, actually have channels cast or forged into them to make the oil have quite a bit of contact before dropping away; Even flowing through the pistons in large volume.

Other engines have them pretty much just because it is a good idea and could do quite well without them.

As previously stated, the fact that this piston ate the fat one previously is not a good sign for the new piston running without its cooling jet.

 

[Cujet]

If I were to guess, I'd say that the spray nozzle is an absolute necessity. I'd also guess that your "easy" driving style matters not with regard to piston cooling. Invisible to the driver/operator, diesel engines are often very heavily loaded, at low RPM. The heat transfer from the pistons is likely insufficient, hence the nozzles.

 

[JHZR2]

Do we know why the piston was replaced?

Yes, the heat load varies substantially with fuel burned, which associated with how hard or "loaded" the engine is. But it's still in an incredibly hot zone where there is flame impingement and all sorts of other means of transferring heat.

It surely would sacrifice life. Question is how much, and does it matter? How many miles does the car have and in what shape is it?

 

[whizbyu]

I believe he had a leak in the gasket and coolant went into cylinder #4 and it eventually blew. That was 5 years ago. I am not sure if the nozzle had been broken for THAT long sitting in the bottom of the oil pan and 5 years later align itslef perfectly to come out the drain plug.
The engine has about 310,00 miles on it. New turbo and new clutch.