Valve problem, what to do?

Sorry for leaving you hanging, I really do appreciate everyone's help! Got caught up in the holidays and travel etc., and finally starting to get back to it. So Mitch, I pulled all the little parts I could find, if there's a clip(?) that holds the lifter together, I haven't found it yet. Speaking of lifters, I'm trying to figure out what to order. When I punch in my serial # 0f154334, and find parts catalogs, there's two options for the "cylinder block and camshaft" - one is "Flat Rollers" and the other is "Roller Lifters"? What's the diff? Is it obvious which one I have, because the lifters are a different part # for each? I'll try to get some more pics of the broken lifter - not sure which side is the bottom. My "friend of a friend" mechanic also mentioned worn lobe as a possibility. I'll try and see if I can see anything down that hole - it's a pretty small hole to try to shine a flashlight and look down at the same time!
 
you have a standard hydraulic lifter
a "flat" tappet is solid...no oil chamber
a "roller" lifter has a little wheel on the cam end
with the manifold off look down the hole the lifter came out of and you are looking at the cam lobe
make sure it is not round...should be egg shaped.
if in question of what you see pull the lifter right next to it and make sure they look alike when rotated
to be sure you can insert a lift guage into the lifter hole and rotate the engine and make sure the readings are the same
keep in mind...intake and exhaust lobes have different profiles and lift..so compare "apples to apples"

edit...put a complete lifter in the hole from the bad one and make sure it goes up and down when the engine is rotated
will work too. if the cam lobe is badly worn it won't move much if at all
 
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My bad, 1996 was first year, Vortec 5.7 with roller lifters. But I did own a 95 180 BR w/a 4.3 Vortec:huh:
 
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susanandlance said:
My bad, 1996 was first year, Vortec 5.7 with roller lifters. But I did own a 95 180 BR w/a 4.3 Vortec:huh:
Click to expand...

!988 was the first year for 5.7L roller cam (center bolt valve covers) and new rear main seal. My 1988 CV-23 has one. Big Block went to roller cam in 1996 Gen VI block, Mike.
 
carterchapman said:
But your picture of the broken lifter does not look like a roller lifter...it looks like a standard, flat hydraulic lifter....
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Yes it is....that is interesting? That block and heads can go both ways I guess. I do see they list both cams for that year....roller and hydro, Mike.
 
CV-23 said:
!988 was the first year for 5.7L roller cam (center bolt valve covers) and new rear main seal. My 1988 CV-23 has one. Big Block went to roller cam in 1996 Gen VI block, Mike.
Click to expand...

1986 1st year 1 pc. rear main seal

1987 1st year roller cam
 
CV-23 said:
!988 was the first year for 5.7L roller cam (center bolt valve covers) and new rear main seal. My 1988 CV-23 has one. Big Block went to roller cam in 1996 Gen VI block, Mike.
Click to expand...
That makes since then, my dad had 5.7 Vortec in a 1993 250 EC. My 1994 Chev truck also had Vortec 5.7 w/center bolt valve covers.
 
standard(hydrolic lifter) or flat lifters are just that .flat on the bottom and are removed by simply lifting them out.
roller lifters have a roller on the bottom and are hend captive by the girdle that must be removed first before you can remove the lifter.
 
Hi Peter , just took a brief read of ur problem. First ...valve guide,seats & clearance are crucial to longevity of cylinder heads. It can start as early as the manufacture. You mentioned an earlier bent pushrod(s)... Again, possible causes, clasped lifter ( hydraulic ), poor lubrication, bad valve seat to valve contact ....& worn valve guide. All those can start a ultimate familiar resulting in a bent pushrod,bent valve (stem) and piston contact. The dented heat shield, under the intake manifold, makes one say Hmmmm,... Was that intake off before and dropped on a bucket of bolts? The good news, from a distance, my guess is that ur block is fine! Worst case ur camshaft lobe(s) are wiped. Ur half way there, kinda, if one lobe is shot, the shaft is shot. Maybe not, do it right and do a complete valve job... No shortcuts...seats , guides, seals... Pushrods and valves if necessary .Good luck ,Tim
 
Ok, so it sounds like the consensus is that I have "Flat Lifters". And I obviously need to take a look down that hole to see what the lobe looks like that. When I am able to do that, I'll get back to you all. Thanks again, for all the help! :eek:)
 
If your cam lobe isn't obviously wiped out and the lift profile proves out as Mopar (Jim) explains in his earlier post; There's one other thing that needs to be observed if you’re considering reusing the cam. Flat tappet cams are ground such that there's a small amount of taper at the top of the lobe, this forces the lifter to rotate in the lifter bore which extends the life of the lifter. It would be impossible to see the taper with the cam still in the engine, though you should be able to see a distinct wear pattern on the lobe. If the taper is still there you will see a highly polished service on one side of the peak of the lobe, as the cam wears the taper is reduced which reduces the rotation. Note that the base of the lobe is ground flat, so the polished area will be across the entire surface and ultimately decrease as it approaches the top of the lobe. If the polished surface reaches more than ¾’s of the way across the lobe I would replace the cam.

Hopefully I explained myself clearly, good luck.
 
Ok, finally got around to taking the lifter out and inspecting the cam. This is what a good lifter looks like (so I'm assuming I really do have "roller lifters", right??? Also found the circlip parts so I don't have to worry that they're lost in the engine someplace.
2013-04-07_13-55-16_748_zpsb66e3699.jpg

Here's a shot down the hole of the top of the cam. I don't see anything that would make me think it's "wiped", take a look. Looks pretty smooth, and so did the roller on the lifter - looked just like the good lifter. So hopefully I'm ok here as well.
18d1470d-de1d-4761-beea-149416a30737_zpsf3adc180.jpg

So then I took off the stbd head. After I removed the valve cover, I found these little bits lying around. No sign of where they came from. The little ones on the left are the circlip from the port side as comparison. Maybe this is what caused my last bent rod a couple of years ago and the mechanic never removed them? Any help?
2013-04-07_16-01-23_828_zps37a23f92.jpg


So my plan now is to take the heads to a machinist and have them do a valve job. Replace all the lifters and rods, and probably my risers and manifolds too, just to be safe. Anything else? Thanks for all your help and encouragement!
 
Just realized as I was looking at that post that that isn't the TOP of the cam. So ran back out and rotated the engine and checked the top, and it looks pretty much like the one next door, so hopefully it's fine.
 
Proper way to check cam would be with a dial indicator and magnetic base. Attach the base to the head and with a lifter in the hole measure the most lift you get. You can compare this to other intake/exhaust lifter whichever you need to compare. After seeing roller lifter I wouldnt think that was it.
I'm more than a bit confused between pictures #13 and #37. What section of your lifter is still missing?
Dont go to the machine shop and say " I need a valve job", show them the parts and describe the problems so they can search for issues.

Bent pushrods are a signal of another problem 99% of the time. They are the weak link in the valvetrain and generally point to a larger issue. They usually bend due to excessive valvetrain slop (broken valvespring, broken rocker, collapsed lifter, stuck/bent valve) or stuck component such as the valve.
I would test the cam lobe lift first and take the head to the machine shop (maybe not the one used last time) have the machine shop check the valve guides and valves. I would have them test the valve spring pressure. Fix whatever is the issue and replace all lifters(soak new lifters in bucket of oil to submerge them so they dont take to long to pump up) and the bad pushrod.
I dont recall if your rockers are adjustable or not, I dont think so but refer to the manual. The metal plate on the bottom of the intake is just a splash shield to keep lifter galley oil off of the underside of the EGR passage where it may cause coking. That damage doesnt appear to be a big deal.
 
As someone stated earlier DO NOT put that engine back together with the egged out pushrod hole.....you can add guideplates to the heads to compensate/save the head (ask your machinest) Also, it takes a lot to wear/wipe out a roller cam, I wouldn't worry about it.
 
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