valve train noise

[moogrr]

I adjusted the valves as per the 1973 factory service manual. .025 I / .030 E. Hot. I noticed the vacuum at idle is up slightly, which is good, but the valvetrain noise is worse. The noise appears to be uniform across the valvetrain, which leads me to believe the adjustment is too loose. I do know the block is original, and the head had a "30" on it as did the cam. Car was built 11/72. Oil pressure checks out.

I did have to open up the clearances a lot, in fact, a couple of adjusters are bottomed out in order to achieve the proper lash.

Thanks for the help;

Ted.

[Zedyone_kenobi]

I do not know how the 73's compare to the 71's, but I used 0.10 Intake / 0.012 exhaust on my stock L24 (1971). If my valves were that lose I would have lots of noise as well.

But again, I have a 71.

[doradox]

.012 inches = .030mm Make sure you are using the correct units.

Steve

[moogrr]

Thanks for pointing out the obvious - wrong units alright. You would think a Canadian could figure this one out on his own, since we're all metric up here... It's not a Mopar to be sure!

[Zedyone_kenobi]

actually,

0.012in = 0.3048mm

again be careful!

[doradox]

actually,

0.012in = 0.3048mm

again be careful!

Or 0.030 mm = 0.001181099 in or so.

So when the FSM says 0.012 inches or 0.030 mm which is correct? I mean you could be off by a couple ten thousandths (in) which could really wreak havoc on the valve train. We really need to get this straight. Did Nissan make a mistake when they wrote the FSM?

Steve

[sblake01]

I've always used the metric setting to where you could move the feeler guage with just a slight amount of drag. Always worked for me.

[doradox]

I was just poking a little fun about carrying out conversions to way too many decimals.

Steve

[Zedyone_kenobi]

.012 inches = .030mm Make sure you are using the correct units.

Steve

I know you were poking fun, but I was pointing out that your decimal is in the wrong place in the mm part of the equation. I think sometimes threads do not convey good messages!

[doradox]

I know you were poking fun, but I was pointing out that your decimal is in the wrong place in the mm part of the equation. I think sometimes threads do not convey good messages!

I think I need to get my glasses checked as I did it more than once. It's funny 'cause when I wrote it I thought it seemed off but didn't take the time to re-check. :stupid:

Steve

[mikewags]

I need to adjust my valve's as well. Anyone got a good video or walkthrough on this? Tools needed would also be good to know.

[moogrr]

FYI;

The motor was allowed to warm up at fast idle until the valve cover was hot to the touch. Temp guage was in the middle of the "E". I adjusted the valves to .010" I .012" E. There was a SLIGHT RESISTANCE to the feeler guage, with the spring removed. Tightening the lock nut tended to decrease the clearance slightly, so double check after doing so. After adjustment, I restarted the motor and it ran perfectly. Smooth and quiet. 19inchs of vacuum at 800 rpm. Pulled beautifully up to 6000 rpm. This motor is growing on me...

My experience has been exclusively with push rod motors, which, incidentally, are nearly always set at around these values ( .010 & .012 ). However, these values in a push rod motor are at the valve stem to rocker arm contact point which is why I initially didn't question my error. My personal opinion is that a LITTLE BIT of noise is preferable to running clearances too tight.

The only other advice I can give is to make absolutely sure the cam lobe is as close to straight up as possible as this cam seems to have a rather gradual rate of rise and can lead to false readings if you don't take care. Other than that, the operation is relatively painless, and there is only 1 valve cover to remove!

Thanks again for all the input.

Ted.