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Discussion Starter #1
Alright Guys, I guess I have a couple questions here, main reason for this disassembly of the top end just for starters is because i've had a wicked clack in my engine, and I am embarrased to drive it around right now because of that clack, it's horrible, so I started some investigation. First of all, it's a v6, but i can't afford a swap yet, and I want to save up and get the right engine, so i want to fix this for now. FYI, I WILL be getting all new gaskets, suggestions on anything else that should be replaced while doing this process is appreciated:

Alright, here's everything pulled off, not yet clean or anything:


Question 1:

Why are those two slots back there covered up with a gasket like metal material?

Question 2:

The same ones that coincide with them on the manifold are also covered up? Is this normal? Shouldn't coolant be flowing or something?

Question 3:

Okay, I wrote distributor there to show you where in peticular I was talking about, see that hole there is all decayed, can I just tap it out to the next size, that hole is the coolant hose coming from the exit of the heater core just FYI. Or should I go get a junkyard one for now? Remember this is a v6, I just want it to run, not perform, that's for later on.

Here's a better picture of that:



Okay, now a question of the lifters, here's just the manifold and valve covers off, showing the lifters, and the retainer to keep lifters in place:


Here is a pic of a retainer that keeps the set of lifters in place for each cylinder:


Question 4: Now here's a pic of the lifters. This is an 88 gmc sierra, since when do they come stock with roller lifters? Isn't that more performance than anything? The original owner used this as a work truck, but DID rebuild it once. Is this more than likely an engine out of a newer truck? Would this indicate that it's been rebuilt on the bottom end too?


Question5: There's a pic of the top, where the pushrod is inserted... they all look like that, that's not collapsed right?


Here's some of the stuff that's been through the parts washer, but I still have to do the manifold, and some nuts and bolts yet :D :


So guys...

Question 6: What the hell is causing the clack? What have I overlooked? I appreciate any help on ANY of my questions. I originally thought it had to be a collapsed lifter, but they all look fine, and they're nice roller rockers to boot! I wanted to ask you guys for some help here before I continue. Thanks a lot!

- Brandon

*EDIT*

All stuff was put through the parts washer except for the Manifold/TBI as those are still in question. :D

 

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#1 Don't knnow why they are there but they are part of the gasket, they will be on the new gasket set (a guess is to force coolant through the heater core)

#2 See #1

#3 That is not a water jacket (at least on the V8's) I have forgotten to tighten after adjusting timing with no leaky/dire consequences. Tapping should be fine, becaeful, you are in aluminum.

#4 I didn't think that they did, and there really is no way to know for sure if the bottom was gone through

#5 Collapsed will have the slot below the lip. (I don't know how to explain it) If they all look the same I would guess it is not a lifter.

#6 Did you ever try adjusting the rockers? Are you 100% certain it is not an exhaust "tick"? Are you certain it is not a rod/bearing clanking away?
 

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1,2,3,4,5 Thanks

6: If im not mistaken, a Bearing would be a constant sound right? Sort of maybe a tick or something?

This is a CLACK CLACK CLACK, but it doesn't happen all the time. When it first starts up, it's sorta alright I guess, but when it warms up it starts clacking like a bitch, and it's really uncomfortable trying to sit at a light and not help but see everyone staring at your truck acting like: "What the fuck, redneck."

Another thing is that it takes a long time to warm up, not sure on that.

If it's a spun bearing that means i gotta pull the engine right? How could I tell? Could I see by dropping the pan, or do I have to pull the whole crank out?

Thanks so much.

- Brandon

Any other input on all is greatly appreciated also!
 

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Bearing isl not necessarily constant, when my bearing went it sounded like a sledge hammer, but was not consistent. Stuff on the lower end really hammers away.

You can pull the pan and plastiguage the bearings to see if they are within spec. I figured it was the lower end on my truck and when I pulled the caps off it was obvious. (see pics) Trust me, i was despartly hoping it was a top end issue.


 

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I am lazy, easier to copy and paste than explain.

This link is awesome, article from carcraft.
http://drcwww.kub.nl/~bogaard/noises/noises.htm

From some other page:

3. My engine makes a clicking noise that gets louder when I rev it up. Is this serious?
It could be. The clicking noise is probably "tappet" or upper valvetrain noise caused by one of several things: low oil pressure, excessive valve lash, or worn or damaged parts.

First, check the engine dipstick to see if the oil level is low. If low, add oil to bring it back up to the full mark. Is the engine still noisy? Check your oil pressure. A low gauge reading (or oil warning light) would indicate a serious internal engine problem that is preventing normal oil pressure from reaching the upper valvetrain components. The cause might be a worn or damaged oil pump, a clogged oil pump pickup screen or a plugged up oil filter.

COLLAPSED LIFTERS
Worn, leaky or dirty lifters can also cause valvetrain noise. If oil delivery is restricted to the lifters (plugged oil galley or low oil pressure), the lifters won't "pump up" to take up the normal slack in the valvetrain. A "collapsed" lifter will then allow excessive valve lash and noise.

VALVE LASH
If you can rule out lubrication-related problems as a cause, the next step would be to check valve lash. On older engines, mechanical lifters require periodic valve lash adjustments (typically every 50,000 kms). Too much space between the tips of the rocker arms and valve stems can make the valvetrain noisy -- and possibly cause accelerated wear of both parts.

DAMAGED PARTS
Finally, inspect the valvetrain components. Excessive wear on the ends of the rocker arms, cam followers (overhead cam engines) and/or valve stems can open up the valve lash and cause noise. So too can a bent pushrod or a broken valve spring.



4. I hear a deep rapping noise from my engine. Is this serious?
A deep rapping noise from the engine is bad news because it is usually due to "rod knock," a condition brought on by extreme bearing wear or damage. If the rod bearings are worn or loose enough to make a dull, hammering noise, you're driving on borrowed time. Sooner or later one of the bearings will fail, and when it does one of two things will happen: the bearing will seize and lock up the engine, or it will attempt to seize and break a rod. Either way your engine will be wrecked.

Bearing noise is not unusual in high mileage engines as well as those that have been neglected and have not had the oil and filter changed regularly. It can also be caused by low oil pressure, using too light a viscosity oil, oil breakdown, dirty oil or dirt in the crankcase, incorrect engine assembly (bearings too loose), loose or broken connecting rod bolts, or abusive driving.

Bearing wear can be checked by dropping the oil pan and inspecting the rod and main bearings. If the bearings are badly worn, damaged or loose, replacing the bearings may buy you some time. But if the bearings are badly worn or damaged, the crankshaft will probably have to be resurfaced -- which means a complete engine overhaul or replacing the engine if the vehicle is worth the expense.
 

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Discussion Starter #7
Your the man, im thinking harder and harder, and this engine isn't worth replacing parts to try and fix, i believe it must be camshaft or bearings, and it isn't worth it to me, so im going to put it back together, if it stopped, awesome, if it didn't stop, oh well, time to save up for engine swap. Thanks again for all this info, im still sifering through it!
 
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