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Quote:

Originally Posted by GregWeld (Post 471894)

Lash caps are a must for high revving motors to protect the valve tip.

Not sure I consider 6500 high reving Greg. In addition lash caps are used to correct drive train geometry.

Quote:

Originally Posted by Vegas69 (Post 471900)

The question is, were the push rods spec'd with or without lash caps?

In order to reach a conclusion I imagine would probably have to put together all the variables and do the math.....how much was removed from the deck of the block, piston to deck dimension, valve stem length, spring assembled height, push rod length, gasket thickness, piston to valve clearance, etc, etc..
As soon as I get the other three rocker arms I'll run the drive train through it's motions and do a little more investigating.

Quote:

Originally Posted by GregWeld (Post 471871)

Appears to me that you have contact with the retainer.... Not an uncommon issue with the aluminum rocker arms.

Make sure you check the rocker arm to retainer clearance. There should be at least .040” to .050” clearance at the closest point under the rocker arm and the top of the retainer.

http://i919.photobucket.com/albums/a...os/file-24.gif

^^^THIS^^^

It's not the proper way... but sometimes you have to grind some on alum rockers to clearence big OD retainers and springs Or install lash caps or longer tipped valves or different retainers if "installed hights" can still be achieved correctly

[QUOTE=Track Junky;471873]

Question is if the timing chain breaking had something to do with it......:headscratch:

If you're asking If the rockers hitting the retainers due to chain breakage The answer is...very unlikely..Hard to tell by the pics, Those look like they've been hitting for a while

Quote:

Originally Posted by Track Junky (Post 471911)

Not sure I consider 6500 high reving Greg. In addition lash caps are used to correct drive train geometry.

and or correct length push rods

In order to reach a conclusion I imagine would probably have to put together all the variables and do the math.....how much was removed from the deck of the block, piston to deck dimension, valve stem length, spring assembled height, push rod length, gasket thickness, piston to valve clearance, etc, etc..
As soon as I get the other three rocker arms I'll run the drive train through it's motions and do a little more investigating.

What exactly are you trying to figure out?? PM me if you like

------------------------------------------------------------------

In this pic, is the roller on the rocker that far back on the valve tip w/ the valve closed, is there lash?? If so your push rods are wrong or that rocker is hitting the retainer and pushing it back

Here is a dumb video but will give you an idea
https://www.youtube.com/watch?v=XnS46ahJVqI

A couple of write ups

http://www.compcams.com/Products/CC-...rods%27-0.aspx

http://www.circletrack.com/techartic...h/viewall.html

http://i2.photobucket.com/albums/y3/...ps94ed6cb9.jpg

Quote:

Originally Posted by Track Junky (Post 471873)

Sounds like you got an early start Mills. My kids are 10, 12, & 14 and this is a great time. I'm trying to spend as much time with them now before they dont want to hang out with Dad anymore.
I heard that if your cup holder can hold a big gulp your a shoe in for OUSCC. :lol:

Lol! Think I'll put one in just for fun! My two boys are 21 and 19, We have more fun now than when they were young! Only the toys cost a bit more! Each has a Honda track only car, plus a few other DD's Grandpa owns a Honda Stealership, I ain't got that kinda cash! Hope you get the motor done today. I don't know how many days I've wasted running around sat looking for parts/tools!

Quote:

Originally Posted by Track Junky (Post 471911)

Not sure I consider 6500 high reving Greg. In addition lash caps are used to correct drive train geometry.

In order to reach a conclusion I imagine would probably have to put together all the variables and do the math.....how much was removed from the deck of the block, piston to deck dimension, valve stem length, spring assembled height, push rod length, gasket thickness, piston to valve clearance, etc, etc..
As soon as I get the other three rocker arms I'll run the drive train through it's motions and do a little more investigating.

I hope you're just going to set the head on the block and use a push rod checker to check for the proper length.... At least that's how I check for proper VALVE TRAIN (I use a different tool for DRIVE trains) geometry. No real math needed using a push rod checker.

[quote=intocarss;471936]It's not the proper way... but sometimes you have to grind some on alum rockers to clearence big OD retainers and springs Or install lash caps or longer tipped valves or different retainers if "installed hights" can still be achieved correctly

Thank Jer, I was not aware that engine builders sometimes have to grind on the rocker arms.

Quote:

Originally Posted by Track Junky (Post 471873)

Question is if the timing chain breaking had something to do with it......:headscratch:

If you're asking If the rockers hitting the retainers due to chain breakage The answer is...very unlikely..Hard to tell by the pics, Those look like they've been hitting for a while

I agree Jer. After further observation it's pretty obvious.

What exactly are you trying to figure out?? PM me if you like

Trying to figure out why the rocker arm is hitting the retainer and why the engine builder did not catch this.

------------------------------------------------------------------

In this pic, is the roller on the rocker that far back on the valve tip w/ the valve closed, is there lash?? If so your push rods are wrong or that rocker is hitting the retainer and pushing it back

Stand by, the pic your refering to has not shown itself this time around
OK I see it now. In that pic #1 is at TDC and both valves are closed so to answer your question, yes. I hadn't checked lash yet as I was trying to figure out if I was going to need the lash caps or not.(Seriously do not recall having lash caps when I pulled the heads off)Obviously I do. I'll have to run down this morning and confirm but If I go with a longer pushrod I'm not sure I will be grabbing enough of the rocker stud.

Here is a dumb video but will give you an idea
https://www.youtube.com/watch?v=XnS46ahJVqI

A couple of write ups

http://www.compcams.com/Products/CC-...rods%27-0.aspx

http://www.circletrack.com/techartic...h/viewall.html

http://i2.photobucket.com/albums/y3/...ps94ed6cb9.jpg

Thanks Jer :thumbsup:

Quote:

Originally Posted by GregWeld (Post 471953)

Thanks Greg. I will order that tool this morning :thumbsup:

Just hopeing a longer pushrod will allow me to grab enough of the rocker stud. Current pushrods are 8.00 in length.

I believe those marks are from clearencing done by the machinist. But I do see one that looks stressed. I think its the one that Greg sees too. Remember this engine was rotated with a few valves stuck down. Could explain this.

Inspect them Geatano and replace or fix the ones that look hammered.

pretty easy to check push rod with white grease and a caliper. if need be buy longer studs

Here is a better view with the spec'd .026 lash. I used a sharpie to black out the top of the lash cap and verify where the roller tip was engaging the lash cap. Looks like it is just behind center.
At this time I'm grabbing about 3/8"-7/16" of the rocker arm bolt.

http://i851.photobucket.com/albums/a...igation001.jpg
http://i851.photobucket.com/albums/a...igation004.jpg

What's it look like without lash?

Got a little motivated and decided to adjust all the valves that I could minus the 3 rocker arms I am replacing that should arrive on Tuesday. I use the quarter crank turn method to adjust valves and decided to put the degree wheel to work for accuracy. Bolted a clothes hanger wire at the water pump boss, installed the degree wheel, and set up the clothes hanger pointer to point to zero. With #1 at TDC I adjusted the intake and exhaust valves with spec'd lash, turned the crank 90*, and then moved on to #8 and so on. The cam I am using has an LS firing order. It has 108 lobe seperation and intake center line is at 104. That means that if I was to line up the dots of the crank and cam gears(setting the cam straight up) I would already be 4* advanced. Advance will give you a little more torque on the bottom end and retarded will shift power to the top end. The beauty of this belt drive set up is that I can adjust up to 4* either way on the fly. Just need to loosen the four bolts on the cam cover and rotate left or right. Degreeing in the cam is best done on a dyno and dialed in for your desired rpm range. I am going to set it up 2* advanced for now per engine builders specs. Once all rockers are installed I'll recheck valve train geometry. Then it will be off to the dyno.

http://i851.photobucket.com/albums/a...Valves1003.jpg
http://i851.photobucket.com/albums/a...Valves1005.jpg