ACCELR8

This is the change I made and now I can hear a tapping noise. I pulled the valve covers again and checked the torque on the rocker arm bolts. Everything checked out o.k. When I started up the car again the noise was still there. I let the car idle for about a minute and the noise didn't dissipate. Is this noise normal when the stock pushrods are replaced? It doesn't seem right to me.

Thanks,

Jim

Naked AV

I believe stock pushrods are 7.36" in length, so when you replace them with 'stock' 7.4" pushrods, you are actually putting in a longer pushrod. Now whether this miniscule difference in length could cause your noise....I'll leave that to someone else to answer.

YOOFORMULA

iTrader: (6)

I thought stock length was 7.400".

ArKay99

iTrader: (1)

I changed mine with TR 7.400's. No difference in valvetrain noise.

M6HuggerSS

i think it may increase noise but who cares???? get a louder exhaust!
after my H/C install you can here the valve train alot more.... but with my cut-out open i cant hear a thing!

2MuchRiceMakesMeSick

No difference in sound here either

ACCELR8

Here's what I did:

1. checked for bent pushrods
2. found one slightly bent pushrod
3. let car sit for approximately a week, until I received the hardened pushrods. During this time all the rocker arm bolts were torqued down except the one where I found the bent pushrod. The lifter associated with that pushrod was unloaded for a week. Could that cause any problems?
4. installed bank 1 pushrods by rotating the engine until both the exhaust and intake valves on cylinder 1 were closed, then I changed the pushrods and torqued the rocker arm bolts to 22 ft/lbs.
5. I did the same for cylinders 3, 5, & 7.
6. once that bank was done I rotated the engine over several times and then checked the torque on each bolt. I made sure the valves were closed when I was checking the torque.
7. I did the same procedure on Bank 2.
8. Then I started the car and heard a loud tapping sound
9. I let the car run for about 1 minute, but the sound did not dissipate
10. about a week later I rechecked the torque on all the bolts. Everything looked good
11. I started the car (this is the first time since the initial start-up) and heard a tapping sound. This time the sound was considerably quieter, but still noticable. The sound did not dissipate.

What's going on? Did I do something wrong?

Note: there was no tapping noise prior to me installing the new pushrods. Oh, the pushrods are 7.400" long.

Thanks,

Jim

HumpinSS

iTrader: (1)

The lifters bleed down after my PR swap it took about 5 minutes for the noise to quiet down. Beleive me that was the longest 5 minutes of my life listening to all that racket anticipating somethihng to blow up

PREDATOR-Z

Well keep in mind that with the hardened ones and stock springs you have no flex on the p-rods. Let it run a couple more minutes at idle.

WAHUSKER

iTrader: (4)

I too would let it run for a couple more minutes. I ran mine without oil pressure after my cam swap (some idiot whose name I won't mention left the oil pump o-ring off....me) & it took about 5 minutes for the lifters to come back completely. (no noise)

ACCELR8

Thanks for the advise! I'll let it run a little longer and then let you know what happens.

Thanks,

Jim

ACCELR8

Well I ran the car today. It took a long time, but the noise finally subsided. I'm guessing a lifter bled down when I swapped the pushrods and just took a while to pump back up.

Thanks a lot for the responses!

Jim

eallanboggs

iTrader: (1)

I think you can answer your own question. If you have a noise that you didn't have BEFORE you changed the pushrods something is different, but by the way you describe your work nothing jumps out. It's going to make some clatter for a few minutes after you initially start it up, but that should gradually quite down after a short period of time. I know it seems like an eternity, but if you were methodical in your work and lubed everything liberally during reassembly you should be OK.

PREDATOR-Z

That is why I soak my lifters and I use a homemade tool to pump them up. I rounded an old valve and with the lifter immersed in oil, I pump them so they get completely filled. You'll know when to stop when there is no more bubbles.