6sally6 wrote:

Somewhat off topic butt............ain't it cool you have people from all over the US look'in and diagniosing your engine problems!?!!
Orange spot makes me think....crack/crapp in the stud.
Guess the commie chineze still haven't figgered out out can't melt rust out of steel. I'm sure they don't give a ratz-a$$ about quality. I mean....what does an 8 year old know about arn & rust?!

One question though.........you are using roller rockers...correct?! How can they be self-aligning? (see your above post)
Just curious...
6sal6

These are roller tip rockers. They are just like the stock ones except they have a roller tip and shoulders on the side to keep them straight, like stock
 

josh-kebob wrote:

6sally6 wrote:

Somewhat off topic butt............ain't it cool you have people from all over the US look'in and diagniosing your engine problems!?!!
Orange spot makes me think....crack/crapp in the stud.
Guess the commie chineze still haven't figgered out out can't melt rust out of steel. I'm sure they don't give a ratz-a$$ about quality. I mean....what does an 8 year old know about arn & rust?!

One question though.........you are using roller rockers...correct?!  How can they be self-aligning? (see your above post)
Just curious...
6sal6

 
He stated hes running Crane roller tip rockers. Look at post 11 and 13.

 
Those rockers are the same as mine but seem to be the self aligning model which have a shoulder on each side of the roller to keep them centered on the valve stem.
I used adjustable guide plates which need hardened push rods.  If I remember correctly the self aligning rockers can use non hardened push rods, don’t quote me on this.
Are your rockers 1.6 of 1.7?

just ordered a endoscope just to be sure

No it was not. but I did have them smashed all the way down when I set them up wrong the first time Im sure

Yes I can see that happening, but why now after all new studs and setting lash per recommendations. At least I think they are pumped up when the motor has run in the last day or so. In fact how can a lifter drain out when the hole is above the center line of the lifters. If that was the case they would not be pumped up after the motor sat for a week or so. Is this more of my problems and I need to pull the distributor and prime before each valve adjustment?  I still fear that the ARP studs are only going to move the problem.

Setting valve lash and checking valvetrain geometry are two different things.  You can't accurately check the geometry in a hydraulic valvetrain with a hydraulic lifter.  If you completely compress the lifter, one you could damage it by doing that, and two the lifter height is now not correct, so any readings taken in such a state are erroneous.  You simply must use a solid lifter to check geometry.  I would never trust a hydraulic lifter, regardless of whether or not it should be pumped up or not.  How could they quickly bleed down?  There are ways/reasons for this, but my point is why take the chance? 

Like Nos681 I also prefer to move the pushrods up and down to determine when all clearance has been removed.  Using the spin method I've never been able to accurately feel where the drag starts and they always end up too tight.  But going up and down its easy to tell when there is no slack and then go 1/4-1 turn past (each person has their own personal amount of preload it seems, personally I go 1/2 turn, but to each his own). 

"The point is............"      whether you do the spin technique or the up & down technique it amounts to the SAME THANG!
Get all the slack/play out of the  rocker/pushrod/lifter assembly   then give it the 1/2 turn!
You are making sure there is NO slack in the adjustment BUTT no pre-load either!   The 1/2 turn just pushes the top of the hydraulic lifter down  approximately half way so it's NOT bottomed out  BUTT it's not too loose either.
Both methods accomplish the same thang.
6sal6

One half turn on a 3/8 stud is .021. 

Bullet Bob wrote:

One half turn on a 3/8 stud is .021. 

 
Can you show your work.  I’d like to understand.

ARP studs on head side is 3/8-16, however the rocker arm side is 7/16-20.

Edit:

I found this information this morning.

https://www.atlanticfasteners.com/tech-tips/how-far-a-nut-or-bolt-travels-in-one-full-turn/

Last edited by Nos681 (3/17/2021 4:41 AM)

Hello everyone this morning,
The current studs are at this time Pioneers 7/16" x 3/8" x 2-1/4" long with no real shoulder to stop them at the head, I think if I had torqued them I would have ran that shoulder down into the head.   They only let me just get the nut on full by 1-2 threads, almost to short. The ARPs will be same threads just 1/4" longer on the 3/8" side so the nuts will be on full for sure. And I can torque them at 50 knowing they are installed correctly. I like the chart showing the depth pr turn too. So pre load is only .021 that's amazing.
Well today is my delivery day so maybe I will be back on the road Friday since we all haven't spotted anything other than cheap studs. I look forward to seeing what the endoscope shows. 

Cab4word67 wrote:

Question
What would you recommend for the thread sealant on the new ARP studs going into the heads as they go into water?
Black RTV, Permatex Aviation, Teflon pipe dope, the red locktite 37701 that says its sealer too?

I've been using Permatex Thread Sealer with Teflon (PTFE).  This is what AFR recommends on the rocker studs even though they do not to into water.  I use it on all the head bolts and the rocker studs.  No leaks from the short head bolts.

Bullet Bob wrote:

Sure...My AFR heads use shouldered studs that are 7/16 - 14 below the shoulder and 3/8 - 24 at the top.  As your chart shows, 24 threads/inch works out to .042 (actually .0417) per thread.  One half revolution = .021.  7/16 - 20 studs at the top will be .050 per thread and .025 for the half turn..  I was assuming 3/8" studs in that answer since the pic on Post #56 appears to be 7/16 down and 3/8 -24 up.
I didn't use a chart, just divided 1000 by the thread count.

 
Thanks for explaining that for me BB, i think I’ve got it now.
Never sat down to calculate it.

Even if you know what the thread pitch is at the rocker stud, that doesn’t necessarily mean the same amount at the valve or the lifter.

How do you calculate the movement at each end of the rocker arm?
Especially since this is at the pivot point.

Last edited by Nos681 (3/17/2021 3:48 PM)