I had bought an N42 head from a guy and just received it last night. It has been rebuilt and then stored without having been used so it truely is a fresh rebuild. However, there was no cam sproket or valve cover and there is some rust in a few places. Please see the pix in my my gallery, there is one where I have pix from all angles in one photo and have circled some of the rust locations in red. I don't understand how the gallery system works, the head pix are scattered throughout my gallery and not in the order I uploaded them either. In short, there is a little on the cam, on the rod that runs parallel to the cam, the manifold bolts, in the little passages on the manifold side, and the piece that hangs off on the plug side of the head.

Can someone please tell me how bad this is for the head and what can be done about it? I don't really want to pay for another rebuild or anything like that. Can this just be cleaned up with something? Does it need cleaned up (I'm thinking yes)? What would be used to clean it up (tools, chemicals, etc)? Should I be mad at the seller for not disclosing this information to me?

As a side note, since the cam sproket is missing are they all the same between the different Z heads?

From what I can see you have a pretty good head. The manifold bolts you should replace anyway. The nipple on the plug side is for your heater core and if in bad shape should be replaced also. The rust you see inside the head is part of the water jacket (where the coolant flows). Looks like the previous owner ran rusty water instead of coolant. Either way it won't hurt your head unless the rust build up restricts the coolant flow. The rust on your cam can be cleaned up with a wire brush and an oily rag. Check the cam lobes for rust . They should be smooth.

I would take the head to a shop anyway and have the head checked for straightness and pressure tested. Everything else can be done at home.

Typically, the valve cover would not be included with the head. I'm with Ed on the manifold studs and coolant connector. That little connector is available for just a few dollars, so it's not so bad to replace it anyway. It will look a lot better too :classic:

On the upper right side in the gallery you can sort by 'latest'. I think it defaults to alphabetical, so that's probably why they're mixed up.

I think the sprockets interchange. You should be OK.

Hope it helps.

Chloe

looks pretty good to me

Are the manifold studs available from somewhere? How do you remove them and install new ones (a special tool)? As long as I can find the coolant connector that should be a no brainer to replace.

On the rust, am I correct in assuming that I should do my best to not allow it to fall onto the head when cleaning it off? I'm very new to engine work and do not know how clean thigs must stay so as to not cause any problems later on.

I would have thought a wire brush onto the camshaft is a no no since the wear pattern between lash pads and camshaft are so delicate you could disrupt things there couldn't you?

I'm not engine expert either still learning just thought it was a bit harsh on something like a camshaft.

I'm with Gav on the wire brush being a no-no, but from the looks of the photos, the rust on the camshaft is not on the lobes. It looks fairly light. I would try an oily rag on those areas of the cam that you noted. That should probably do the trick.

Yes, try to keep anything from falling into the head. For the studs, I believe that the Nissan studs are readily available, but I could be wrong. Some of the suppliers have "upgraded" stud kits, but I don't have any experience with those.

There are stud remover/installer tools. The cheap installer tools will usually hurt the threads of the stud. There a lot of choices for tools. There are also "free" ways to get those in and out (2 nuts tightened against each other and a wrench, etc.), but you might find the money spent is worth the time and frustration saved.

Chloe

brass bristles

even steel bristles prolly wouldnt be hard enough to hurt anything but brass is very soft

Originally posted by nutxo

brass bristles

even steel bristles prolly wouldnt be hard enough to hurt anything but brass is very soft

Steel brush bristles most certainly ARE hard enough (most are stainless steel) and small enough to cause problems in an engine. Brass bristles are softer, but you don't want that junk floating around in your engine either. :stupid:

Just my $.02

Carl

When I mentioned the steel brush I was talking about between the lobes. From the picture that is where I saw the rust. If the lobes had any rust on them I would probably think twice about using it. Be sure you do keep any engine parts as clean as possible. Something as small as a grain of sand can really bugger things up. When you remove the studs spray some WD-40 or other penetrating oil at the base of the stud and let it sit overnight. You can use the two nuts tightened together trick. Be carefull and work the stud loose. Don't force it or you will end up with a broken stud and that is a different story. You should be able to pick up new studs either from the dealer, VB or MSA.

Good luck.

Please be kind, I'm new to the terminology too. If the lobes are the shiney parts of the cam that make contact with the rocker arms (is that the right name?) then you are correct, there is no rust on that area only between them and also really only near the front of the cam.

What is the rod that runs parallel to the cam that I indicated has rust on it too? What's it's function/purpose?

Originally posted by Ed

When you remove the studs spray some WD-40 or other penetrating oil at the base of the stud and let it sit overnight. You can use the two nuts tightened together trick. Be carefull and work the stud loose.

You can also soak a cotton ball in your favorite penetrating oil (I like KROIL) and then rest the cotton ball on top of the stud at it's base. This seems to allow a bit more "penetration" of the fluid into the areas where it is needed.

Right Ed, you'd never want to wire brush the cam lobe, but even with brushing off surface rust elsewhere, I'd be very careful to not allow even one wire bristle to get into the valve train. Might even pull the cam to do any scrubbing like that, but that's just me.

My prior response was more pointed to the statement that "even steel bristles prolly wouldnt be hard enough to hurt anything but brass is very soft." which I do not agree with at all.