454 Firing Order/Distributor alignment

[1970BannerBlazer]

Originally Posted by AussieinNC

Replace the guide and both pushrods.

Those measurements sound correct.

I would be checking the other bank as well for misaligned rockers....the guides are usually the culprits...

Good news/bad news.

Good: no bent pushrods on the passenger side.
Bad: the rocker bolts where on so tight I had to pull out the 1/2” drive and use my entire force to get them off.

I think I’m going to switch over to studs with locking nuts.

Thoughts?

[geezer#99]

It’s good they were tight, they’re supposed to be torqued to 50 ft lbs.

[1970BannerBlazer]

Originally Posted by geezer#99

It’s good they were tight, they’re supposed to be torqued to 50 ft lbs.

Everyone else is saying tight is bad.

[geezer#99]

Tight is bad with the older style rocker and nut, not with the newer style like you have.
Until you posted pics everybody assumed you had the older style.

Screw in studs are available if you convert to the older style. However they are 3/8 inch on the bottom and 7/16 on the top. Your heads have 3/8 inch threaded holes. If you want to make a 7/16 stock screw in stud fit you need to drill the holes out and rethread to 7/16.

[AussieinNC]

IMHO....

No need for screw in studs and nuts...just adds costs all round.

The rocker bolts being that tight means someone used an impact drive to install the bolts...not recommended.

Re-use the bolts, clean out the threads in the head and on the bolts with brakeclean and use a little dab of Blue loctite on the bolt threads. Torque to 50lb as others have recommended.

Replace that worn guide plate and the two damaged push rods.

Start it with the covers off and let it idle for a little while so the lifters can bleed out as needed.

If you have any rockers that "clack clack " after a few minutes, you may have bad lifters or a bad lobe on the cam....

Good luck...Bill

[1970BannerBlazer]

Originally Posted by AussieinNC

IMHO....

No need for screw in studs and nuts...just adds costs all round.

The rocker bolts being that tight means someone used an impact drive to install the bolts...not recommended.

Re-use the bolts, clean out the threads in the head and on the bolts with brakeclean and use a little dab of Blue loctite on the bolt threads. Torque to 50lb as others have recommended.

Replace that worn guide plate and the two damaged push rods.

Start it with the covers off and let it idle for a little while so the lifters can bleed out as needed.

If you have any rockers that "clack clack " after a few minutes, you may have bad lifters or a bad lobe on the cam....

Good luck...Bill

I have the rockers and pushrods reinstalled. New guides. Everything torqued to 50lbs. Have been idling it for 20 min plus. Lots of rockers that are still clacking. Some have stopped or minimized. Others haven’t. None clacked prior to me going on this journey.

How long should I wait for them yo pump up? Should I run it at higher rpm to boost the oil pressure? I don’t think the lifters are bad since they didn’t have issues prior.

[AussieinNC]

Is it possible to drive the truck around for a little while ?

Sometimes they take a while to bleed thru.

What weight oil is in the engine?

Are the original failed pushrod cylinders the ones that are noisy?

If the cam lobes / lifter bottoms have been damaged you have bigger issues than the noise.

[1970BannerBlazer]

Originally Posted by AussieinNC

Is it possible to drive the truck around for a little while ?

Sometimes they take a while to bleed thru.

What weight oil is in the engine?

Are the original failed pushrod cylinders the ones that are noisy?

If the cam lobes / lifter bottoms have been damaged you have bigger issues than the noise.

I drove it around and nothing changed with the noise. The clatter is coming from pushrods that weren’t changed and were fine prior. I think I have 20-50 oil in there. I don’t think the cam is damaged or I would have heard an issue prior. I only pulled the rockers and pushrods on these to make sure they weren’t bent. All were good except for the one.

Now that I think about it, I did change out the pushrod retainers. Maybe the Comp Cams retainers I put in are thicker than the ones I took out? That would cause the rocker to lift just a tad. But then I would expect all of them to clatter. Not just some.

Maybe my lifters just aren’t pumping up.

[geezer#99]

Or maybe your cam was on the way out when you first started this thread and now it is really getting wiped out.

[kwmech]

What kind of oil pressure do you have?

[1970BannerBlazer]

Originally Posted by geezer#99

Or maybe your cam was on the way out when you first started this thread and now it is really getting wiped out.

Maybe but 6 out of 16 rockers chatter when they didn’t prior?

[1970BannerBlazer]

Originally Posted by kwmech

What kind of oil pressure do you have?

60 at idle. 70 running.

[1970BannerBlazer]

I’m going to move this into it’s own thread to get more eyes on the problem.

[geezer#99]

Did you figure this out yet?

[AussieinNC]

Started a new thread for more exposure

https://67-72chevytrucks.com/vboard/...d.php?t=835491