Valve cover hose? What is it? So many hoses!!

[Serdriver]

Hello all,

Im in the process of Trying to fix that water outlet leak at the back of the engine (Im almost there!). In the process Im changing the upper and lower intake gaskets, throttle body gasket, IACV gasket, valve cover gaskets, pcv valve, and spark plugs. And there are sooooo many hoses in this truck.

Problem is, some of these hoses are brittle, and I’ve already broke two of them. Looking at the EM section of the service manual, most of these hoses are not labeled, so I don’t know where or how to replace them. Some of them are pretty straight so I assume I could go to O’reilly or similar and get replacement, but some are strangely shaped.

I’m attaching pictures of one hose that goes from one valve cover to the next. It has a little bend in it, and I’m pointing to it with my hand. What’s this called and how do I replace it?

I also broke the PCV hose, but I think that should be easier to replace?

Is there a standard size/gauge for all these hoses? So many tiny little hoses that crack when you slip/pry them off. I don’t want a vacuum leak when this is all out back together.

Any help would be appreciated.

[Serdriver]

Ha! I answered my own question after searching for valve cover hose. It’s called a breather hose! And they are quite expensive for a hose! Hopefully local auto parts store has it.

[Serdriver]

Im putting the part number here (with pictures of the diagram) in case anyone in the future needs this.

The part number is 11823-4W006. The website says it’s been replaced by 11823-4W00A, but I think you can use either number.

Btw this is from nissanpartsdeal.com
Here is the link: https://www.nissanpartsdeal.com/parts/n ... 5=LE;6=AT)

Also included is the diagram of the hoses.


Im thinking I should replace all of those hoses since I already snapped two of them.

I have a lot of build up inside the engine, and the PCV valve is really gunked up with oil. I’m guessing the truck was burning oil/run without correct amount of oil for these to just snap in half as I was taking them out? Who know, the truck ran fine, no codes or anything, no sluggish performance, but I’m replacing these parts Because of the water leak.

Thanks for all the answers lol. Sometimes you just have to say things/type things to yourself in order for them to make sense.

[Mike W.]

Not a Nissan expert, but knowing cars in general fairly well, I think breather hoses are more on the fragile side. They generally don't have any fiber reinforcement like pressure hoses like fuel lines do, and need to be hard enough when new not to collapse under vacuum. Preformed makes them fit better especially since they would want to collapse if bent and under vacuum, but also means universal isn't going to work. If it's any consolation, them breaking is not just a Nissan problem.

[AlanAZ]

I have a lot of build up inside the engine, and the PCV valve is really gunked up with oil.

How many miles on the truck? Have you already replaced the valve cover gaskets (or valve covers)? You are replacing the upper thermostat?

[Serdriver]

145k on the truck, just bought it a few months ago, so don’t know if they have been changed, but guessing they are original.

[AlanAZ]

Is oil dripping on the ground? I'm at the same 145K miles, and my original valve covers in dry, hot Phoenix climate, are weeping so badly that I can see oil drops forming at the rear lower covers of the covers. Replacing them is my next big project, and I'll be doing much of the same work you are.

[Serdriver]

Surprisingly no oil drip. I had an oil drip from a leaky oil cooler, but once I fixed that no oil on the ground.

This week I’m planning on cleaning those valve covers, changing plugs, and then trying to get to the water pipe leak.