Power Valve Screw Repair and Timing Chain Rattle Repair

[Legend11]

Hello,

I finally have the motivation to do as many preventative maintenance and and repairs to my 2001.0 QX4 as possible. I have been dealing with an oil consumption problem (currently using 5w30 Mobil 1 High Mileage and loses about 1-2 qts per oil change) and Timing Chain Rattle on cold stars since I first purchased my QX4. I was concerned that the oil consumption was tied to Power Valves being sucked into the engine, but it appears that I am fine . All screws are intact
Should I be concerned about the Yellow paint marks near 2 of the screws? Do they mean anything? I'm hoping that doesn't mean they were replaced before Also, is that oil/crud normal to see in here? It's not much, but I did notice a little in the upper intake and manifold as well.

Going forward, I investigated both valve covers and there appears to be some seeping from both, but the driver side is definitely saturated. I plan on replacing both. Besides thoroughly cleaning both with brake cleaner, is there anything else I should replace? I believe I read somewhere about an updated Valve Cover design which may help with oil consumption; I 'm not sure if anyone has done this on this forum.


Further investigation shows some really bad hoses (especially the one connecting to the passenger valve cover wit the crack! (it was so bad, it felt like plastic and not rubber! ) ) I will plan on replacing as many of these as I can.

So far everything is going well, I will be removing the radiator alternator, and other misc. items in order to access the timing chain cover next. So far the forum, service manual, and having the right tools has been very helpful. I will continue to update this thread with pictures as this project continues.

Thank you

[Legend11]

The fun continues... Take a look at my PCV Valve:


If that wasn't enough, my drive belts are terrible! Probably original and it's a miracle they didn't break; even one was splitting in half!



Now, while investgating the Timing Chain Rattle, I took out the Radiator to get to the small Timing chain cover where the tensioner is. I expected to see a broken timing chain guide today, but to my surprise the guide looks fine (Just covered with sludge!). I'm starting to wonder because of all the sludge and my truck being a first year design with the VQ35DE (2001.0), the tensioner might just be bad and I'll need a newer version (At least that's all I hope it is). I'm still willing to do what's needed to investigate, but I'm wondering if I should start by simply replacing the Tensioner through the small cover to see if my problem is resolved.. Wanted to get everyone's thoughts on the Timing Chain rattle being caused by the tension er and anything I can do to clean this sludge up. I've been doing regular oil changes with good synthetic oil.


Thank you and I appreciate any help. Anything that is supposed to be Rubber is hard plastic at this point. Can't wait to get these issues resolved!

I'll be doing spark plugs and new belts tomorrow...

[AlanAZ]

... and new belts tomorrow...

Thanks for all the photos, very helpful.

Check also the belt adjuster pulley bearings (see youtube videos for what good vs. bad bearings sound like.)

How many miles on your truck, and what oil filters are you using? I'm about the same oil consumption at 120K mls, M1 0w40, and 7K mls OCI.

[Buzzman]

First of all, I was going to say, replace your PCV valve while you have the intake removed. It can't be replaced without doing that.
Secondly, just looking at the internals of your engine from your pics, I'm inclined to think that the last owner was somewhat negligent on his oil changes and general maintenance.
How long have you had the truck, and how many miles were on it when you bought it?

[Legend11]

I bought the truck with 125,000 miles on it about 1.5 years ago. It currently has 136,000. Since I bought it, I've been using Mobil 1 Synthetic 5w 30 High Mileage oil. I'm probably going to start using an additive to clean-up the internals (MMO?). I just ordered a brand new Timing Belt Tensioner from Nissan to replace the one in the pic.

I ordered a bunch of new parts last night. I'm going to replace all the following things this weekend before putting the truck back together:
-PCV Valve (OEM Nissan)
-All 4 Crankcase ventilation hoses including PCV hose and split hose in pic (OEM Nissan)
-2 Drive Belts (OEM Nissan)
-Spark Plugs (NGK Platinum)
-Fuel Filter
-Main Timing Chain Tensioner (OEM Nissan)
-Water Pump and 2 ring gaskets (OEM Nissan)
-Thermostat and gasket (OEM Nissan)
-Water Control Valve and Gasket (OEM Nissan)
-Red Threadlocker for Power Valve and Swirl Valves
- 2 Valve Cover Gaskets (OEM Nissan)

I'm going to thoroughly clean the insides both valve covers and Intake Manifolds (upper and lower).

Anything else I should replace while I have everything off? If the timing belt tensioner doesn't stop the rattle by itself, I'm going to possibly replace the Timing Chain, 2 secondary Timing Chains, 2 secondary timing chain tensioners and guides later this summer. This is about $450 in Nissan parts so I'm hoping the Tensioner is all it needs

[atraudes]

Sounds like you got this thing nailed down good For the straight dope on valve covers, check out this thread. It may be possible to use the updated valve covers, but it'll take some tweaking. You're probably better off reusing the aluminum set you have. I'd pop off the rivets on the baffles, have the whole thing cleaned by a machine shop, reattach the baffles, and pop them back on. If you end up doing that, please post on that valve cover thread with your findings, notably whether cleaning them helped your oil in the intake problem. A couple of us have this on our summer todo list.

[Legend11]

I appreciate the info on the link. I don't know anything about rivets or how easy they are to remove and install, but I will take a look into. Definitely want to soak some type of cleaner in there to clean as much of it out as I can. I'm also on the fence on buying a new timing chain, secondary timing chains, guides, etc... Figure I should brake clean/degrease as much as I can so I hopefully won't have to do this again. I will report my valve cover findings in that other thread. Thank you

[Legend11]

@Atraudes Do you know any chemical I can soak the valve covers in for a night or two? It doesn't look like much fun popping/drilling out the rivets. Thanks

[04pathse]

@Atraudes Do you know any chemical I can soak the valve covers in for a night or two? It doesn't look like much fun popping/drilling out the rivets. Thanks

I believe many people soak them in Kerosene...