reusing stock valvetrain parts?

[cj71z]

I was wondering if I get my head rebuilt with new seats/guides and seals can I just reinstall the old lash pads since I'll be using my old cam and rockers? I'm assuming that this return the wipe pattern to the way it was or am I misleading myself. My head has some serious valvetrain clatter, eventhough I've adjusted the valves. Since it makes so much noise, when I get it rebuilt should I just replace the entire valvetrain?

[Arne]

If you use the old cam, use the matching rockers. (Keep the rockers matched to the same lobes.) If you use new rockers or cam, replace it all.

[Carl Beck]

Given the noise you mention and the fact that you have the head off anyway- and out being redone.. I'd buy a complete new cam kit... Cam, Rockers, Springs, Retainers. I'd also replace the timing chain, chain tensioner, guide and gear.

Make sure that the shop that rebuilds your head - knows Z's... All to many times when installing new valve seats.. if they don't know better.. you wind up with seats that were set too far into the head.. which means that the valve stems will push too high in the valve train. - and at that point you have to start changing the lash pads.. Not all the sizes of lash pads are easily available any more either.

If it's a lower mileage engine - and the cam, rockers etc are all within the Factory Spec.'s - no reason to change them out - as long as you were very careful to keep the original rockers with their mating cam lobes. Again the thickness of the lash pads is determined by where the valve seats wind up being installed in the head.

FWIW,

Carl B.

[26th-Z]

Some interesting comments! It is impossible to set a new valve seat too far into the head. The head is machined to recieve a proper seat. There are specs on this in the FSMs. By all means don't work with any machine shop that doesn't know what they are doing. (At least, I don't)

The noise you are talking about can come from a number of sources including the timing chain and tensioners. However, the wear pattern on the rocker arms, cam lobes, and the valve shims is critical and will cause noise if any of it changes. In all probability, the noise you are hearing now was caused by something that was changed. I agree with Carl in that as long as you are going this far, you might as well do it all. Especially if your prmary reason for doing this at all is because of noise. Don't forget that worn cam chains and tensioners are noisy also.

[cj71z]

The noise came worse after my last valve adjustment. Now all valves are at spec, but it clatters like crazy especially after I drive it for a while. It's interesting that people say to use new rockers because I've found posts on other sites claiming resurfaced rockers work just as well. I'm thinking about taking it to rebello for the seats and guides and doing the cam setup myself. I'm assuming that if I resurface my rockers all I'll need is new lash pads and a cam. MSA sells lash pads for 50$ for a set of 12 and webcams sells regrinds for 160$ All together I figure about 500-600 dollars total. On the other hand I've read that valve clatter is natural, since the car seems to run fine would it be ok to continue to drive it like this, or should I get the work started to stop any further damage.

[26th-Z]

MSA sells Schneider products. http://www.schneidercams.com/ I bought a whole kit including cam. rockers, lash pads, springs and retainers for the $600 figure. "Rebello" sounds a lot better than "Tom and Tommy's Machine Shop", and I think you have a good plan.

I wouldn't say that valve clatter is natural depending on how much noise you are talking about. How many miles do you think you have on the valve train?

[cj71z]

I have about 126k on the stock valvetrain. This engine has never been gone through so the orig seats and guides are still in the head. I originally was going in to fix the burning oil problem from the stem seals, looks like I'll be doing alot more than that.

[Ed]

You can get reground Nissan rockers from Delta at about $3 each (excange). They can also regrind your cam. Once it's all installed you will have to check your wipe pattern on the rockers and adjust lash pad thickness accordingly.

http://www.deltacam.com/

[zcarnut]

You can get reground Nissan rockers from Delta at about $3 each (exchange)...

Their exchange price has gone up to $4 per follower (at least that's what they just charged me). Still a bargin when compared to the dealer cost of $29 a piece.