Roller Rocker Install DIY, Top Dead Center???

[bwhitmore]

I am installing my roller rockers this weekend. I bought the Harland Sharps and T&D pushrods from Roe Racing. These rockers are mounted in pairs, that is both the intake and exhaust valve rockers are connected via a small shaft and so the OE rockers and pushrods have to both come off at the same time on each cylinder to swap them with the new ones. The instructions say to mount and adjust the rockers in pairs this way, but I was not aware that there was a place in the firing order when both rockers have their lifters at the heel of the cam for proper adjustment. So if there is a place like this, and how do I know when I have gotten there? I plan to turn the engine over by hand with a socket on the crank pulley.

 

[HOdbleFman]

Both valves are closed during the compression stroke of the engine. Install the rockers with the studs and rotate the engine until movement in the rocker arms is no longer evident. This will put you on the base circle of the cam, then go ahead and turn it a few more times. Since the cam rotates at half the speed of the crank, this will ensure that you are somewhere on the base circle of the cam. Once you get them in this position you can go ahead and adjust them properly. Make sure you have checked your pushrod length. You don't want the adjuster cup on the back of the rocker arm to be too deep into the rocker arm. Not only is it possible to cut off the oil to the rocker tip, but you can also create a side load on the adjustment cup that will cause it to fail. That particular brand of rocker arm is not forgiving in that respect.

 

[bwhitmore]

Thanks, I got the T&D 7.500 pushrods as Sean suggested with the rockers. The instructions say to start off with the adjuster cup installed with one thread showing below the rocker arm and adjust 1.5 turns past no play in the pushrods.

BTW, do you know what the size of the bolt head is on the crank pulley? I need to get a socket big enough, I only have ones that go to 1" and it is bigger than that.

 

[vipergts2000]

When are you doing the install, tomorrow? I want to do my car as well. I would like to come by and check it out if that would be cool.

Shawn

 

[Jack B]

A couple of insights: it is very difficult to turn the engine over from the the balancer. If you succeed let me know how you did it. It is just as simple to use a push button off of the solenoid.

A very valid comment was made about the correct length. It is so simple to measure for the correct rod length, why not do it right. The wrong length push rod could be catastrophic. Our cars have different length push rods from the factory, no one can guarantee that the .750 will be absolutely correct.

Contrary to opinion the push rods can be adjusted cold. The sweet spot (take-up range) on the lifter is far greater then any expansion from heat. One last item,make sure that the roller is seating in the center of the valve. Use some magic marker to verify.

 

[bwhitmore]

Jack,

Thanks for the reply, the instructions that are included are pretty clear that the adjuster cup should be 2 1/2 threads below the bottom of the rocker for proper oiling and that typically the 7.500's accomplish this. I will certainly check that out before buttoning everything up though. I plan to go pick up a remote starter and adjustable pushrod to have handy for the install.

Shawn,

I planned to do the install Sunday mid day, but that is assuming all goes well with getting the tools I need and making the time for it. Why don't you PM me a phone number I can reach you at.

Brian

 

[Jack B]

2-1/2 threads or 2-1/2 turns?? Too far down weakens the adjuster and can limit the flow of oil. Another caveat, just because oil flows out the push rods when you crank does not mean it can flow sufficiently at high rpm's.

 

[Bill B]

One other warning. Hold on to the pushrod when removing and installing. They can fall inside the motor.

 

[ROCKET62]

A couple of insights: it is very difficult to turn the engine over from the the balancer. If you succeed let me know how you did it. It is just as simple to use a push button off of the solenoid.

Pretty easy IF the spark plugs are out.

 

[J DAWG]

One other warning. Hold on to the pushrod when removing and installing. They can fall inside the motor.

been there and don't wanna go back.


remote starter will work fine. check the roller tip position on the vavle as Jack said as well.

 

[1TONY1]

Thanks, I got the T&D 7.500 pushrods as Sean suggested with the rockers. The instructions say to start off with the adjuster cup installed with one thread showing below the rocker arm and adjust 1.5 turns past no play in the pushrods.

BTW, do you know what the size of the bolt head is on the crank pulley? I need to get a socket big enough, I only have ones that go to 1" and it is bigger than that.

Bigger than 1" ... I "think" 1 1 /4" but not sure. Get you a bump switch and watch the intake valve, shortly after the intake valve closes the piston is coming up for the compression stroke. I use a 8" or 10", 1/4" extension stuck in the spark plug hole AFTER I know the piston is coming up.....until you get used to this, only manually turn the engine at the balancer bolt (yes, you must be careful) You can carefully bump it up to near the top and then manually turn the engine (this is what I do) When you do the first one, put a piece of tape on the extension to line up with the spark plug shield (leave the shields in place to support the extension) Adjust both valves at TDC. You do not have to install the rockers one cylinder at a time. Back the adjuster nut all the way out on the new rockers and you can remove all the stock rockers and install all the new rockers at the same time. When tightening the lock nut on the rocker, tighten it to 1/8 turn shy of where you want to be and then tighten/pull the adjuster AND the nut another 1/8 turn....this will lock them together....done correctly they will never loosen. I like to see oil flow at idle on a new rocker install. The location of the adjuster (reference oiling)may not have to be perfect.....I have seen t&d's already on cars that have come to the shop that run a very wide range from above and below the recommended "spot"

 

[vipzilla]

saving so i can find this thread later

 

[MattInNC]

BTW, do you know what the size of the bolt head is on the crank pulley? I need to get a socket big enough, I only have ones that go to 1" and it is bigger than that.

31 MM, but a 1-1/4" works as well

 

[Jack B]

Thanks, I got the T&D 7.500 pushrods as Sean suggested with the rockers. The instructions say to start off with the adjuster cup installed with one thread showing below the rocker arm and adjust 1.5 turns past no play in the pushrods.

BTW, do you know what the size of the bolt head is on the crank pulley? I need to get a socket big enough, I only have ones that go to 1" and it is bigger than that.

The bolt data is in my write-up. If you haven't bought the rods yet you may want to measure first. Sean is guessing, it is a good guess, but, not 100% sure. It only takes a little effort to measure.

 

[0209 CLK]

I'd like to check out the install as well if thats ok with you. I tried to send you a PM but your inbox is full.