rocker arm problem

[confucius_Sez]

ok, it is a shaved cam lobe. i just don't know how it happened in less than 300 miles. i believe i adjusted the rocker arms down appropriately prior to starting the motor. the lifter was cupped on the under side and i was able to pull it out of the hole.

anyways, what's the best way to get the shaved metal dust out of the oil galley? should i use the distributor primer i made and get all the oil circulating to try to get rid of the oil before more problems arise. so other than the metal dust and replacing the cam, lifters, what else should i check for?

when it stops raining over here in southeast texas, i'll get to work. (maybe, sincei i have all 4 kids here, they can help me push it in the garage!!!!) :O)

laters, joey

[Oldtruckfanatic]

Unfortunately it sounds like it shaved that lobe off the cam. Did you break the cam in after the rebuild (run it at 15-1800 rpm for 15-20 minutes) you must do this to insure the lifters start spinning like they are supposed to if you don't they start wearing the lobes down all the way. until it's round. if you remove the intake and try to remove that lifter it will probably jam up in the bore. this is caused by the lifter "cupping" as it wears the lobe off. essentially it makes a bowl in the face of the lifter and flares it slightly at the tip making it very hadr to remove. I wish I could say it was something else but it sounds like a flat lobe.

[confucius_Sez]

yes, the break in was around 2000-2200 rpms for 1/2 hour plus. it is a brand new cam and lifters. what do you mean by the lifters spinning? circular or up and down (lifting). so the bowl effect would mean where the cam and lifter meet or the lifter and pushrod? cuz that would suck if its at the cam/lifter. means i would have to take out the damned motor again.

[Captkaos]

Were you varying the speed per the break-in procedure? How were the valves adjusted before you broke the cam in? Were you using new lifters and new cam?

I also think you wiped the lobe off.

[swervin ervin]

Could very well be a collapsed lifter too. I've seen this happen before. Looks like you may have to pull the intake to see what is going on.

Edit; One other thing it could be is the rocker arm stud pulling out of the head as you tighten the rocker. I've also seen this happen.

[confucius_Sez]

if i was supposed to vary the speed, then no, i didnt' do it per procedure, but i did vary it by mistake then. i did bring it down to 1500 for about 10 minutes to make some other adjustments, after it ran for 20mins at around 2000 or so (on the higher side)

another observation is this. i used a straight edge across all the rocker arms. all but the #1exhaust (first on driver side) rocker is aligned. the #1 exhaust rocker is just slightly higher than the rest. i haven't checked nor taken off the intake manifold since i'm headed to work here in a little bit.

yes i used new cam/lifters/pushrods/rollertipped rockers/springs and was told the pushrods didnot have to be any extra length. i'm hoping it's just a collaped lifter. though, can that be bad as well? or just a simple swap?

hey, i appreciate ya'lls help. i'll have pix of her all polished up soon. even though she just sits there for now. like ya'll, i'm not ever done.

[piecesparts]

I am betting that you have a collapsed lifter. I realize that this may sound critical, but it would help diagnose the problem; Did you pump up the lifters with oil before installing them? A lot of guys will let them soak in a bath of oil to fill th elifters, others will use a squirt can to fill them with oil just as they install them. What you have described sounds like one lifter is not pumped up or it has failed in the collapsed condition.

[Slonaker]

This article was pointed out to me AFTER I broke my new engine in.

http://www.competitioncams.com/infor...yID=1821071676

I have been told that GMs break-in lubricant (I think it is called EOS) is recommended like the stuff competitioncams is trying to get you to use in their article.

BTW, the cam can be changed with the engine in the truck if you need to. Swervin has an article on it on 73-87.com. I have done it, and it will work.

Slonaker

[confucius_Sez]

Originally Posted by piecesparts

I am betting that you have a collapsed lifter. I realize that this may sound critical, but it would help diagnose the problem; Did you pump up the lifters with oil before installing them? A lot of guys will let them soak in a bath of oil to fill th elifters, others will use a squirt can to fill them with oil just as they install them. What you have described sounds like one lifter is not pumped up or it has failed in the collapsed condition.

hmmm, no i did not pre-oil them other than breakin lube. so would i be able to use the same lifter or should i buy a new one (or set) and replace them all after the pre-oiling? if doing so, would i have to do another cam break in run? also, while the lifter is out (on that particular cam lobe) how can i tell if the lobe is shaved off? would the lifter show it, or looking down the hole would tell me? i appreciate the information guys. joey.

[swervin ervin]

IMO, pre-oiling or pumping up the lifters is a waste of time and not a good thing to do. It will give false readings when trying to set the lash before starting the engine and they will pump up very quickly after it starts anyway. Besides, you are not going to get them pumped up very much anyway.

You done nothing wrong by not pre-oiling them. As a matter of fact, it sounds to me like you done everything right. If indeed you do have a collapsed lifter, it's just a freak act of nature. Stuff like this happens from time to time. One thing that can cause it is cheap lifters. What happens is the spring in the lifter weakens and breaks or just collapses. You will be able to tell very quickly if the lifter is bad. You will be able to push it down without much trouble.

As to being able to tell if the lobe is alright by looking down through the lifter hole, it's a shot in the dark really. It may look just fine but indeed may be going bad. Once a lobe starts to wear, it's only a short while until it's totally gone. Then you usually end up with bigger problems, such as metal shavings all through the engine and in the bearings.

I wouldn't risk damaging the engine if it were me. I'd pull the cam and make sure everything is in good shape.

[piecesparts]

OK I guess that there is a difference of opinion in preoiling lifters. I have done a few engines in my time and if a lifter is not pre oiled then setting the lash without starting the motor and running it to adjust the lifters is virtually a hard messy task. Yes it can be done, but it is a lot cleaner on the old shop floor to adjust before starting. The problem that you may get into is that if the lifter does not have oil in it, then your initial setting could be to tight and that may cause the valve on that cylinder to be put into a bind. It depends on the person doing the assembly and how much knowledge that person has.

I still contend that you have a collapsed lifter and I would look at the cam outside of the engine, just as Swervin said. It will mean removing the timing chain cover, but now is the time to do it, not after the engine is toast.

[swervin ervin]

By no means am I trying to start an arguement or prove I'm right but it is useless to preoil lifters. I have done many, many rocker arm adjustments in my 51 years and have never preoiled lifters. I never make a mess on the shop floor because I adjust them before ever firing up the engine. You don't need oil in a lifter to adjust it. You are not adjusting against any oil pressure anyway. You adjust against the spring inside the lifter. The oil then pumps the lifter up after the engine is running. What you are after is getting the lifter as close to center when adjusted. Of course us power rpm hogs want a little extra and instead of going the full turn past zero lash (as GM recommends), we go 1/2 turn or less for that little extra range in the upper rpm before the lifters floats the valves.

On a side note, I've never lost a lobe or lifter to date.

[confucius_Sez]

hey, ervin. someone mentioned you have a technique for removing the cam w/o taking the motor out. where would i find that?

the lifters were a package deal with the crane energizer cam. part #100172 (summit) hopefully it is only a lifter and not a shaved cam. and if so, that the damage is minimal (something an oil change would fix) to remove the metal. i'll let ya'llknow how it goes. also, when i take out that lifter, if it is a worn down cam lobe will the lifter show worn as well? or is the lifter a harder metal than the cam? i do appreciate y a'lls responses.

joey.

[Slonaker]

Originally Posted by confucius_Sez

hey, ervin. someone mentioned you have a technique for removing the cam w/o taking the motor out. where would i find that?

http://www.73-87.com/7387garage/drivetrain/cam.htm

It is a little more complicated if you have A/C because the condenser is in the way. I unbolted the clamp that holds the aluminum parts of the A/C hoses to the inner fender make them more flexible, and used a piece of string to hold the condenser up while I did the cam.

When I cut the core support, I made the cut at the bottom and bent it out of the way. I spliced it back together with a piece of sheetmetal and fastened it with some self drilling sheetmetal screws. I shot it all in black, and you could not tell it was ever cut.

Slonaker

[piecesparts]

The cam can be pulled while the mot0or is in the truck---the radiator will have to come out and the A/C condensor moved to a point that it is out of the way. The core support in the middle of the grille will have to be cut or removed. Then the timing chain cover comes off and the cam can be removed (after the lifters are taken out).

[confucius_Sez]

let me entertain this question. if indeed the lobe is shaved off, when i did the passenger side rocker adjustment, all the rockers were working properly and no knocking and going thru the full motion (from my naked eye) so wouldn't that mean that the lobe is intact and just the lifter that is ?collapsed? or effed? or am i just totally wrong.

[swervin ervin]

The passenger side rocker arms has nothing at all to do with the drivers side. Each valve has it's own lobe on the cam. A V8 cam will have 16 lobes, 8 intake and 8 exhaust. Here is a pic I found on Comp Cams website. It's GM Duramax cam so it has no fuel pump eccentric like yours will have but you can see all the lobes. It's a big pic, so I'll just provide a link to it.

http://www.compcams.com/Base/Images/...maxCam_001.jpg

[confucius_Sez]

ok, that is clear. anyways, i'll get to working on it first thing monday. i've been so busy working graveyards and other things. i appreciate everyones help. beer is on me!