Push rod through rocker

[IQ52]

Cam specs......which include recommended parts.
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1497&sb=0

Valve spring 911-16 single w/damper........925-16 dual w/damper
1.524" o/s diameter.................................1.509"
1.110 i/s diameter................................1.125"
Inside diameter of inner...........................0.697"
Spring rate 373.......................................395
Spring height/psi
1.950/104................................................92
1.900/122...............................................111
1.850/141...............................................131
1.800/160...............................................151

1.400/309...............................................309
1.350/328...............................................329
1.300/346...............................................349
1.250/365...............................................368

Coil Bind 1.200"........................................1.175"

Were Comp Cams lifters used in this build? If so, which ones? Some of them require the used of adjustable rocker arms. The 822-16 can be used with stock rockers. The 867-16 required adjustable rocker arms.

And the 107 lobe separation decreases the piston to valve clearance.

 

[413 belvedere]

Yeah, there it is two pages left in the catalog. Hydraulic Flat Tappet, Mutha' Thumper 21-601-5, 287/304, 235/249 @ .050" .497"/.483", 107 LSA. Turns out there are two Mutha' Thumpers, hydraulic flat tappet and hydraulic roller.

I'd really check those valve spring pressures. The suggested single spring, 911-16, has even more seat pressure than the 925-16 alternative dual spring that is suggested as an upgrade. If valves are floating and hitting pistons, that will punch the pushrod right through the rocker arm.

Stealth heads are notorious for the pushrods hitting the intake runners of the heads. There isn't enough machined clearance on the outside of the runner in the pushrod pinch area. When that happens all kind of nasty things can happen.

They are the springs that came on the stealth heads, he checked them and said they were good for the cam I'm running, he did change the keepers he said they didn't seat very well, I did look and the pushrods are close to the heads but looked like enough room.

 

[413 belvedere]

Cam specs......which include recommended parts.
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1497&sb=0

Valve spring 911-16 single w/damper........925-16 dual w/damper
1.524" o/s diameter.................................1.509"
1.110 i/s diameter................................1.125"
Inside diameter of inner...........................0.697"
Spring rate 373.......................................395
Spring height/psi
1.950/104................................................92
1.900/122...............................................111
1.850/141...............................................131
1.800/160...............................................151

1.400/309...............................................309
1.350/328...............................................329
1.300/346...............................................349
1.250/365...............................................368

Coil Bind 1.200"........................................1.175"

Were Comp Cams lifters used in this build? If so, which ones? Some of them require the used of adjustable rocker arms. The 822-16 can be used with stock rockers. The 867-16 required adjustable rocker arms.

And the 107 lobe separation decreases the piston to valve clearance.

Cam specs......which include recommended parts.
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1497&sb=0

Valve spring 911-16 single w/damper........925-16 dual w/damper
1.524" o/s diameter.................................1.509"
1.110 i/s diameter................................1.125"
Inside diameter of inner...........................0.697"
Spring rate 373.......................................395
Spring height/psi
1.950/104................................................92
1.900/122...............................................111
1.850/141...............................................131
1.800/160...............................................151

1.400/309...............................................309
1.350/328...............................................329
1.300/346...............................................349
1.250/365...............................................368

Coil Bind 1.200"........................................1.175"

Were Comp Cams lifters used in this build? If so, which ones? Some of them require the used of adjustable rocker arms. The 822-16 can be used with stock rockers. The 867-16 required adjustable rocker arms.

And the 107 lobe separation decreases the piston to valve clearance.

Not sure which lifters he used, can find out but I am going with adjustable roller rockers, also I have a pretty low compression motor 8.9to1 so not sure if valves will be hitting pistons

 

[IQ52]

They are the springs that came on the stealth heads, he checked them and said they were good for the cam I'm running, he did change the keepers he said they didn't seat very well, I did look and the pushrods are close to the heads but looked like enough room.

I too believe that, properly set up, those springs should work with that cam.

 

[miller]

Hate to say it, at this stage of the game...but, might also consider checking for any bent valves. That RPM backfire you mentioned, sure sign, for whatever reason, valve wasn't closed on the stroke.

 

[413 belvedere]

Hate to say it, at this stage of the game...but, might also consider checking for any bent valves. That RPM backfire you mentioned, sure sign, for whatever reason, valve wasn't closed on the stroke.

What's the best way to check, can I just make sure all valve tips are equal height

 

[khryslerkid]

What's the best way to check, can I just make sure all valve tips are equal height

That would be a start. It might show if a valve isn't completely closed as long as all of the valves are the same lenth and seats are the same.
I would use compressed air in the spark plug hole with the rockers removed. Listen for escaping air in the carb (intake) or air in the exhaust (exhaust valve)

 

[Ski 61701]

If you have a long enough machinist ruler or something like it set it on top of the valve stems on the head and then take a feeler gauge and check to see if you can slide it under the valve tips. With the ruler across the tips it can give you a visual reference to see if any of the valves / springs are not in line. I agree with the Kid and put some air in and listen for leaks. Id wire back the throttle so it might be easier to hear if its an intake exhaust is going to be a litter harder if you have an exhaust valve if its ever so slightly leaking. Depending what your ring gaps are you are probably going to hear air noises coming from dipstick tube. Just get ready to have all of your Spidey senses going when it comes to listening. Good luck

 

[miller]

Yeah, to a point, I agree...too many variables, especially if a valve took a hit. Considering how bad some of your push rods are bent, something went bad! Hung lifter, sticking valve...who knows! Not without some good checking.
Are you planning to make a change on those valve springs? Just comparing the valve tip heights could easily mean nothing. Not unless you had 'hands on' working the valves, and seats. Just cutting the seats 'should' be done with all of them the same depth. Do you know? If you are going to change springs (and pull the heads), simple to do a liquid leak check. Heads belly up, and give 'em a drink...if their leaking, they'll let you know.
The air check will work, too, but your adding in leakage past the rings. But, it can be done!

Sorry...cogs are spinning...just trying to look at the whole picture. All that mess has to work together, or no tango, like you have now. Best of luck on it!!

 

[413 belvedere]

Did some more checking and found out the lifter preload on lifter is about 113 thousand, would that cause the problem

 

[Ski 61701]

That is way too much. You are checking this with the lifter on the heel of the cam correct? Which rocker arm are you checking with the first ones that were on the motor or the replacement they used. I have a feeling with your mixed match of rocker arms you might get readings all over the place.

 

[413 belvedere]

They way I did it was put the lifter on the back side of the cam, measured top of lifter to top of lifter cup then subtracted top of life to retaining clip, probably not the correct way to do it. Would that be close though

 

[413 belvedere]

OK did it again, lifter back side of cam, top of lifter to top of cup is .249 the undid rocker no pushrod top of lifter to top of cup is .128, so o think that gives me 121 thousand preload? am I wrong

 

[Ski 61701]

What I would do if I were you is get a checking pushrod (if you havent done so already) and use it to get a definitive measurement. But if you are getting roller rockers they use the ball and cup pushrod so everything you are doing now is not going to help you with the new rockers. Then you will need a ball cup checking pushrod to get proper preload on the lifters

 

[413 belvedere]

Yes getting a ball and cup pushrod checker, just wondering if that could of been the problem

 

[Ski 61701]

Depending on how you are measuring your current set up, using anything other than a checking pushrod is trickey. Not saying it cant be done it can be but its hard because you have to take in consideration the end of the pushrod might not set completely into the cup of the rocker as you mentioned earlier that some rockers fit the pushrod tight and others were loose. If your measurement are correct you could have problems at higher rpms. The biggest thing i could see happening depending on your current set up depending on coil clearance that extra preload could put the coils into a stack mode and with not enough travel you start breaking things

 

[413 belvedere]

Depending on how you are measuring your current set up, using anything other than a checking pushrod is trickey. Not saying it cant be done it can be but its hard because you have to take in consideration the end of the pushrod might not set completely into the cup of the rocker as you mentioned earlier that some rockers fit the pushrod tight and others were loose. If your measurement are correct you could have problems at higher rpms. The biggest thing i could see happening depending on your current set up depending on coil clearance that extra preload could put the coils into a stack mode and with not enough travel you start breaking things

Yea, maybe, just hope roller rockers and new pushrods help and don't bend or break anything else

 

[miller]

Yea, maybe, just hope roller rockers and new pushrods help and don't bend or break anything else

Unless those 'roller rockers' are adjustable, they won't do squat, without your push rods being the right length.
Measuring the tappet pre-load...forget about the top of the tappet...doesn't have anything to do with it. First, you must decide how much pre-load to shoot for...saying that because even with a # in mind...it will vary a little, once the motor is running. That's the whole idea behind hydraulic tappets! A little leeway, a workable 'range' that the tappet will work correctly in.
Somehow, you need a method to get the measurement you need for the push rods.
Yes, cam base at the tappet...measuring from the rocker arm to the tappet cup. Pre-load measurement is only from the TOP of the tappet's cup (piston) to the bottom of the snap ring/retainer. That distance the tappet's cup is pushed in is pre-load, simply keeping the tappet's cup OFF the retainer. And, allows the tappet piston movement through it's cycle.
I use a wire gauge to measure pre-load. If I want .030 pre-load, use a .030 thick wire. When the wire will go into the gap, between the retainer, and top surface of the tappet's piston...it's there.
Agree, or disagree, pre-load should be minimum .020/max .040. Some say .040 - .060. Pick your poison!

 

[413 belvedere]

Unless those 'roller rockers' are adjustable, they won't do squat, without your push rods being the right length.
Measuring the tappet pre-load...forget about the top of the tappet...doesn't have anything to do with it. First, you must decide how much pre-load to shoot for...saying that because even with a # in mind...it will vary a little, once the motor is running. That's the whole idea behind hydraulic tappets! A little leeway, a workable 'range' that the tappet will work correctly in.
Somehow, you need a method to get the measurement you need for the push rods.
Yes, cam base at the tappet...measuring from the rocker arm to the tappet cup. Pre-load measurement is only from the TOP of the tappet's cup (piston) to the bottom of the snap ring/retainer. That distance the tappet's cup is pushed in is pre-load, simply keeping the tappet's cup OFF the retainer. And, allows the tappet piston movement through it's cycle.
I use a wire gauge to measure pre-load. If I want .030 pre-load, use a .030 thick wire. When the wire will go into the gap, between the retainer, and top surface of the tappet's piston...it's there.
Agree, or disagree, pre-load should be minimum .020/max .040. Some say .040 - .060. Pick your poison!

Thanks for the input, engine builder says .050, I've heard .020 to .040, but going to get a pushrod checker from engine builder, and hopefully be around 40 to 50, and yes they are adjustable rockers .

 

[413 belvedere]

Hope this helps