Procedure for adjusting adjustable roller rockers. Preload?

ricardoa1

Registered User
Im buttoning up stuff but I tried putting on the Motorsports 1.7 studmounted rockers on my new set up and having variable results..

I first mounted the stud and guides.. and then torqued to 25ft/lbs. Keep in mind these studs are larger then the stock bolts so the bosses on the heads have already been machined flat for the guides and drilled and tapped for the larger studs.

Next is the rockers and the nut with the little screw stops....

I turned the nut till I felt resistance and then turned it 3/4 turn and locked them. Problem is some of them dont give resistance until the pushrod is already collapsing the lifter. I seem to get rockers that are too tight and some that feel loose after I rotate the engine.

Whats the right way before I put on the valve covers on....
 
I always soak my lifters before install..Also a good idea to pump up your lifters before attempting to tighten. You never know if you have a collapsed or sticking lifter. Keep in mind hydraulic lifters are made to have a bit of preload. Instead of writing it all out for you a quick search on the net yeilded a good resuklt

http://www.flowtechinduction.com/technical.htm#Valve http://www.flowtechinduction.com/technical.htm#Valve

People get scared of adjusting for some reason but its pretty straight forward
 
Do you have the intake manifold installed, or is it off still? you should be able to easily sense zero lash with your fingers. turn the push rod clockwise and counter clockwise with your fingers as you ever so slowly tighten the adjusting nut. as soon as you feel any change in resistance, you are at zero lash.

The leverage you have with the adjusting nut makes it terribly easy to push the lifter down. Thus you have to be very sensitive to your fingers as you rotate the push rod.

If you are like some people had have little feeling in your fingertips, you may want to see if someone with a lighter touch can help.
 
Intake is back on. Valve cover is still off. I have to redoit

Ricardo,

My Haynes manual has a procedure listed where you can adjust all the valves using only two differnt crank positions, and you don't need to see the lifters. I'll post it this evening.

David
 
The problem I encountered was also with these guides I have, not sure what brand they are. It is very hard to align the guides so they dont interfere with the pushrod during full travel. The heads were machined flat where the studs go. The guides can swivel anyway they choose and can come close to the pushrod during travel. These things are extremely hard to set up IMO.
 
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I problem I encountered with these guides not sure what brand they are. And it is very hard to align the guides so they dont interfere with the pushrod durning full travel. The heads where machined flat where the studs go. The guides can swivel anyway they choose and can come close to the pushrod during travel. These things are extremely hard to set up IMO.
I had a similar problem with my guides, but was able to work through it. Just be patient.
 
The problem I encountered was also with these guides I have, not sure what brand they are. It is very hard to align the guides so they dont interfere with the pushrod during full travel. The heads were machined flat where the studs go. The guides can swivel anyway they choose and can come close to the pushrod during travel. These things are extremely hard to set up IMO.

The guides should have been pinned to the head, then they would not try to rotate. Also, if those are 7/16" studs I hope you put more than 25ftlbs on them or they will loosen up. They should be torqued to about 40lbs or so.
 
Keep it comming Im glad you saw that I only put on 25ft/lbs the stock torque.

What do you mean by pinned. These things rotate where ever they want I have to hold it with my fingers while tighten with the other hands....

They look like the lower case letter h and are flat.
 
Keep it comming Im glad you saw that I only put on 25ft/lbs the stock torque.

What do you mean by pinned. These things rotate where ever they want I have to hold it with my fingers while tighten with the other hands....

They look like the lower case letter h and are flat.

Probably not to easy to do now, but when the heads are milled you line up the pushrod/rocker arm and then drill and pin the plates to the heads. Either that or you can weld them into pairs but that doesn't work 100% either.
 
Probably not to easy to do now, but when the heads are milled you line up the pushrod/rocker arm and then drill and pin the plates to the heads. Either that or you can weld them into pairs but that doesn't work 100% either.
Yeah, mine are welded into pairs, but before they are torqued, some of them are slightly warped at the weld and slightly bind on the pushrods until the guide plates are torqued flat.
 
Procedure for positioning the cam to set lifter preload and secure rockers.

Position crank to TDC "zero" with #1 cylinder on the compression stroke.

In this position adjust and secure the rockers for the following valves/cylinders.

Intake: 1, 3 & 6
Exhaust: 1, 2 & 4

Rotate crank clockwise 360 degrees to TDC "zero"

In this position adjust and secure the rockers for the following valves/cylinders.

Intake: 2, 4 & 5
Exhaust: 3, 5 & 6

I've used this procedure numerous times to set the rockers on my car, without removing the intake manifold to see the lifters.

David
 
Procedure for positioning the cam to set lifter preload and secure rockers.

Position crank to TDC "zero" with #1 cylinder on the compression stroke.

In this position adjust and secure the rockers for the following valves/cylinders.

Intake: 1, 3 & 6
Exhaust: 1, 2 & 4

Rotate crank clockwise 360 degrees to TDC "zero"

In this position adjust and secure the rockers for the following valves/cylinders.

Intake: 2, 4 & 5
Exhaust: 3, 5 & 6

I've used this procedure numerous times to set the rockers on my car, without removing the intake manifold to see the lifters.

David


That's how I do it. Makes it super easy to feel zero lash.
 
That's how I do it. Makes it super easy to feel zero lash.

How does that procedure affect lash "feel"?

It is not always easy to find the point of zero lash. When the lifters were removed from the motor they may have been partially into their travel, in which case they may not be completely full of oil. In this case the plunger will depress very easily for a certain amount making it nearly impossible to "feel" zero lash. In this case pumping up the lifters ahead of time may help to alleviate the problem.

Setting lifter preload should always be done with the intake manifold off so that you can see exactly what you are doing. There is generally no reason to be setting lifters after the intake is on but if you find yourself in that position, it can be a bit frustrating finding zero.

The easiest and most accurate way to set lifters is to have them completely empty (as opposed to full as some have indicated) and then set preload off the bottom of travel rather than the top. To set them from the bottom you just use a .060-.090" feeler gauge and it's a go/no-go deal. You can't hardly screw that up. But if the lifters have any oil at all in them then you have to measure preload.
 
Done, a combination of Neiberts TDC post, primed engine and some finger feel and a call to Dalke got it done. Valve covers are on.

Thanks

I gotta say now that I went tru it seems much better then using the fixed ones and playing with shims. LOL
 
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