Moparts
Valve train question
Posted By: bigcountry
Valve train question - 02/11/13 05:35 AM
Hello all, had my 69 A12 Superbee out a few weeks ago cruising the streets when I heard a poping noise coming from the carb. Limbed about five miles home doing under 20 mph..Took valve covers off and noticed pushrod had punched a hole thru rocker arm on number 5 cylinder exhaust valve. Took rocker arm shaft off and fished out the lifter and noticed that it too had a hole punched in it. Have never heard of a push rod going thru both lifter and rocker arm before and can't figure out how it could be possible. The valve is not stuck. Put lifters, rockers and rocker arm shafts from another 440 in and it seems to run fine. Any ideas on what the cause of this is? Most people don't seem too concerned, but I would like to know what caused this. Thanks and take carer, B.C..
Posted By: RapidRobert
Re: Valve train question - 02/11/13 04:50 PM
Hyd lifter I'm assuming. Piston to valve collision? How much preload do you have? More details on what was punched thru on the lifter.
Posted By: Yellow Fever
Re: Valve train question - 02/11/13 05:07 PM
You took used lifters from another motor and put them in? I doubt it will last very long, should have just put one new lifter in or all new lifters.
Posted By: JohnRR
Re: Valve train question - 02/11/13 05:22 PM
Quote:
You took used lifters from another motor and put them in? I doubt it will last very long, should have just put one new lifter in or all new lifters.
I was thinking the same thing , good luck ...
Posted By: bigcountry
Re: Valve train question - 02/12/13 03:28 AM
Yes hyd. lifters..don't know what the preload was, it had shims on the shafts along with lifters that were a little longer. Guessing shims were used for preload and to offset longer lifters to allow for clearance. Lifters were only put in to make sure engine was not further damaged. New lifters will be installed this weekend. The push rod went thru rocker arm and was wedged about 1.5-2 inches thru rocker arm.
Posted By: RapidRobert
Re: Valve train question - 02/12/13 04:54 AM
I'd pull the valve springs off of the offending cyl with an on eng valve spring compressor & check piston to valve clearance with a pair of light checking springs. The rocker arm could have failed from high spring pressure but you said the lifter was punched thru also. I would suggest some more checking unless you're sure V/P clearance is adequate
Posted By: bigcountry
Re: Valve train question - 02/12/13 05:21 AM
Yes both lifter and rocker were punched thru. Can't figure out why piston to valve clearance or spring tension would become an issue at this point?? Motor probably had 3000 miles on it with this setup. Any ideas? By the way thanks for all the input and help.
Posted By: Pacnorthcuda
Re: Valve train question - 02/12/13 05:33 AM
Push rods wearing through the stamped steel stocker rockers is not unheard of at all. A pushrod punching a hole Ina lifter ??? Would lie to see a pick of that! Can't see both happening either.
Weird.
Posted By: cudaman1969
Re: Valve train question - 02/12/13 05:50 AM
I would check to make sure oil is getting to the rocker arms, were any restricters put in the block? Unless a big cam they should last many many miles.
Posted By: bigcountry
Re: Valve train question - 02/13/13 05:16 AM
Plenty of oil on rocker arms, shafts and lifters.Seems to me pushrod would have to punch hole in lifter first, since it was wedged 1.5 inches approx. thru rocker.
Posted By: jbc426
Re: Valve train question - 02/13/13 02:25 PM
When you're saying the pushrod punched a hole through the lifter, can you describe what that looks like or post a picture?
Did the lifter have a hole through the bottom of it and look a bit concave where it meets the cam?
Posted By: JohnRR
Re: Valve train question - 02/13/13 03:40 PM
Quote:
Yes both lifter and rocker were punched thru. Can't figure out why piston to valve clearance or spring tension would become an issue at this point?? Motor probably had 3000 miles on it with this setup. Any ideas? By the way thanks for all the input and help.
Was the block decked and the heads surfaced also ? Adding shims under the rocker shafts is the WRONG way to fix what is one of your real issues ... pushrods that are TOO LONG.
Posted By: bobs66440
Re: Valve train question - 02/13/13 04:12 PM
It seems to me the pushrod would bend before punching a hole through the lifter.
There's a lot of metal to go through on a lifter...and if it went through the lifter first, the pushrod probably couldn't even reach the rocker arm and vice versa.
Posted By: moper
Re: Valve train question - 02/14/13 03:05 AM
If the lifter face had a hole in it (worn) you can stop doing anything and closely inspect the camshaft without the intake in place. You have engine damage and the more you swap in used parts and run it the more damage is done. If the cam lobe that killed that lifter is also damaged (and no, it running with another used lifter for ANY time is not helping) then you have serious repairs. Inspect it. Closely. Immediately.
Posted By: bigcountry
Re: Valve train question - 02/14/13 05:30 AM
Well the pushrods from both 440's are the same length. Have the heads been surfaced/block decked...will have to check, I dont know. The lifter face is not where the hole was punched, it is on other end where pushrod meets. The lifters I pulled from Superbee are a little longer than the ones that I pulled from, another 440. Put the two different lifters side by side WITH the shim on top of shorter lifter and they are the exact same length. I figured the shims, which are NOT homemade, were added under the rockerarm shafts for clearance??I was told shims were used before ajustable rocker arms were around?
Posted By: bobs66440
Re: Valve train question - 02/14/13 11:45 AM
Yes, the shims are used to adjust lifter preload. Some say they really aren't a good idea because they effectively increase the diameter of the rocker shaft, which makes them too snug for the pedestals in the head and causes them to crack. I've never actually seen one crack, so I'm not sure if it's true, but it sounds logical. Adjustable rockers are better, but expensive. If you want to use the stock rockers, the correct way to adjust preload is to get a custom set of pushrods made. That's what I did with mine.
Posted By: moper
Re: Valve train question - 02/14/13 06:07 PM
Shims are "bad" because they move the centerline of the rocker shaft. That in turn can negatively affects the path the rocker follows - they affect the geometry of the rocker. So you add shim to adjust for the wrong pushrod, and the rocker tip ends up riding slightly off in terms of it's path accross the top of the valve. So for the cost of pushrods you run the risk of wearing the guides faster, valvetrain instability, wearing the rockers faster, and wearing the valve stem tips faster.
Posted By: MoparforLife
Re: Valve train question - 02/14/13 06:23 PM
Quote:
Well the pushrods from both 440's are the same length. Have the heads been surfaced/block decked...will have to check, I dont know. The lifter face is not where the hole was punched, it is on other end where pushrod meets. The lifters I pulled from Superbee are a little longer than the ones that I pulled from, another 440. Put the two different lifters side by side WITH the shim on top of shorter lifter and they are the exact same length. I figured the shims, which are NOT homemade, were added under the rockerarm shafts for clearance??I was told shims were used before ajustable rocker arms were around?
Case height of the lifters don't mean didily. The preload is determined by the depth of the plunger after the rocker shaft is tightened down with the lifter on the base circle of the cam with the lifter, push rod, and rocker all in place. 
Posted By: rowin4
Re: Valve train question - 02/14/13 06:34 PM
Normally shims are used when the heads have been milled. When nonadjustable rockers are used if the heads are milled the push rods will hold the valves open. If both the rocker and lifter were damaged I would look closely at the rocker shaft for galling and the valve sticking. Your problems just are not normal.
Posted By: bobs66440
Re: Valve train question - 02/14/13 06:38 PM
Quote:
Quote:
Well the pushrods from both 440's are the same length. Have the heads been surfaced/block decked...will have to check, I dont know. The lifter face is not where the hole was punched, it is on other end where pushrod meets. The lifters I pulled from Superbee are a little longer than the ones that I pulled from, another 440. Put the two different lifters side by side WITH the shim on top of shorter lifter and they are the exact same length. I figured the shims, which are NOT homemade, were added under the rockerarm shafts for clearance??I was told shims were used before ajustable rocker arms were around?
Case height of the lifters don't mean didily. The preload is determined by the depth of the plunger after the rocker shaft is tightened down with the lifter on the base circle of the cam with the lifter, push rod, and rocker all in place.
Exactly right. When I was building mine, I had two different brand lifters side by side. They had different overall heights but the distance from the plunger and the face where the lifter meets the cam was the same. That's the dimension that matters. 
Posted By: bigcountry
Re: Valve train question - 02/15/13 05:32 AM
Thanks for all the reply's. Plan on putting a new set of lifters in it and give it a go. Might buy a new set of heads for it this summer and if I do I will go with an adjustable roller rocker setup.
Posted By: MoparforLife
Re: Valve train question - 02/15/13 11:19 AM
If you aren't going to use a big cam with high spring pressure with a tendency for side loads, rollers are a waste of money. Get a set of doctile adjustable rockers or leave well enough alone. for a street engine you will likely notice very little difference in the ratio difference in the OEM and the more accurate adjustables. Here is a excerpt from a Mopar mag. It is referring to small block but the same holds true for bb engines.
Posted By: jbc426
Re: Valve train question - 02/15/13 12:10 PM
Quote:
Thanks for all the reply's. Plan on putting a new set of lifters in it and give it a go. Might buy a new set of heads for it this summer and if I do I will go with an adjustable roller rocker setup.
How many miles do you have on this motor since this all happened?
It's kind of surprising you don't have a flat/ damaged cam lobe already from running those used lifters, and you'll be taking another chance when installing that new set.
A lot of people on this board aren't so lucky even with all new parts.
I hope this all works out for you and you've Dodged a bullet.
Posted By: Dodgeguy101
Re: Valve train question - 02/15/13 02:37 PM
I would be asking why did it only happen on one? If all these assumptions were correct, you would have 16 pushrod problems, not one. IMO.
Posted By: MoparforLife
Re: Valve train question - 02/15/13 05:34 PM
Quote:
Quote:
Thanks for all the reply's. Plan on putting a new set of lifters in it and give it a go. Might buy a new set of heads for it this summer and if I do I will go with an adjustable roller rocker setup.
How many miles do you have on this motor since this all happened?
It's kind of surprising you don't have a flat/ damaged cam lobe already from running those used lifters, and you'll be taking another chance when installing that new set.
A lot of people on this board aren't so lucky even with all new parts.
I hope this all works out for you and you've Dodged a bullet.
Over ther years Ihave seen people that put the lifters in a box and reused them when reassembling. Making sure that the lifters and cam are clean and well lubricated and they end result was no problem. Granted it isn't a good idea but if you have run it for even a relatively short time with no problem I would not worry about it and run it. Save your money for later up grades. The damage would have been virtually immediate.
Posted By: bigcountry
Re: Valve train question - 02/16/13 04:53 AM
Quote:
I would be asking why did it only happen on one? If all these assumptions were correct, you would have 16 pushrod problems, not one. IMO.
That is why I asked this question. Most people say it just happens sometimes BUT I want to know the cause. These lifters have less than 15 miles on them plus 10-15 min idle time after installing them.
Posted By: RapidRobert
Re: Valve train question - 02/16/13 05:10 AM
I say V/P collision from valve float or something momentarily siezed from inadequate clearance. All pieces in related assy's are different (clearances/yield points etc) & will act different under fire. For a start I would check V/P clearance on ANY cyl. Something stacked em up solid (K.I.S.S. = vp collision)
Posted By: 74yellowduster
Re: Valve train question - 02/16/13 03:26 PM
Quote:
I say V/P collision from valve float or something momentarily siezed from inadequate clearance. All pieces in related assy's are different (clearances/yield points etc) & will act different under fire. For a start I would check V/P clearance on ANY cyl. Something stacked em up solid (K.I.S.S. = vp collision)
yes this. and over 6000-6500 rpm or so (plus or minus) hydraulic lifters will pump up solid and cause problems. i dont think you were running over 6k, so it's more likely that your pushrods could be too long.
if you like running high rpms you should have solids (this requires adjustable rockers).
do you have a good local machine shop? you should go explain the issues they would probably show you how to measure things and get it right. you might need a cut-to-fit pushrod kit and the guys at the machine shop can help you get your baby right
my recommendation: get a solid cam / solid lifers / adjustable rockers / cut-to-fit pushrods / pushrod measuring tool / have a machine shop help or teach you all the details / know how to adjust them you will never have these problems again 
Posted By: ek3
Re: Valve train question - 02/17/13 04:36 AM
Quote:
I would be asking why did it only happen on one? If all these assumptions were correct, you would have 16 pushrod problems, not one. IMO.
it can not be put more simply than that. lifters dont just get holes sometimes. post a photo of dammaged parts.......
Posted By: bigcountry
Re: Valve train question - 02/17/13 11:57 PM
How do you post pictures here?
Posted By: Dodgem
Re: Valve train question - 02/18/13 12:13 AM
one way is to leave I want to preview my post and/or attach a file
checked then it will have a place to choose file to attach file must be resized small enough to be allowed.
Other is to go to Photobucket.com join upload your photo there click the photo and there will be a links box to the right click the IMG line (second from bottom) the come hear and paste in your post Ctrl V or use paste in browser and line shows up and will show as a picture after you post
Posted By: bigcountry
Re: Valve train question - 02/19/13 05:55 AM
Thanks Dodgem, I will try that soon.