DerrenZ

Current questions:

1. Is there any way possible that an engine block with number 183169 (as shown above) could have been originally installed in a vehicle with VIN 2G2FV22G522160639??
2. Do most people eyeball this 75 degree turn to torque the con rod bolts? Is this usually just fine?
3. I have literally only looked at the bottom half of each con rod bearing. They look fine. I can go dislodge the upper halves, but is it possible to find significant damage to only the upper half of the bearing set? I would think if the bottoms are fine the uppers are too?
4. The piston slap that is associated with LS1's--is it detrimental? Is it a sign of wear? Is it... bad?
5. And what other problems, like those suggested by 88 350 tpi formula, could cause a knocking noise and how do I diagnose them? (see posts #45 & 46)

Pocket

iTrader: (24)

Just learn the definitive sound of a knock vs the sound of other noises

If the lower halves look that good, no way the uppers have anything wrong with them

Have you pulled the valve covers yet? Any loose rocker arms? Broken spring? Compression test?

Pocket

iTrader: (24)

1) Cant say for sure

2) More or less. A degree wheel is preferred but marking the bolt with a sharpie and estimating will work fine. Good time to stick some ARP bolts in there which have a specific TQ spec

3) Upper and lowers are almost always mirror images of each other. Those look fine, Id button them up and not worry about them

4) Piston slap is the piston rocking slightly inside the cyl bore when its cold. As it warms up it expands so the already minute gap is tightened so you dont hear it anymore. Only detrimental if you run it hard when cold which will hurt any engine really. It doesnt seem to speed normal engine wear to a degree to worry about. Just as many original build high mileage early LSx engines with piston slap as later LSx engines without

5) If someone dropped something metal, bolt, washer, nut, pebble etc into the intake and it got sucked into a cyl, all hell can break loose and make any sort of terrible noise. A loose heat shield, stone wedged behind the heatshield or simply something banging againt the chassis/exhaust can sound like a bottom end knock. Whacking the exhaust system with a rubber mallet may help track this down but eyeballing it usually spots trouble areas. Running the engine sans belt lets you hear specifically the engine for a short period of time. If say the alt bearings are totally shot and are making bad noises, removing the belt will isolate the issue to being external. If the sound remains, look outside first, then possibly dig in. Five7kid suggested the converter bolts being loose as was a common problem with OEM 3rd gens. It sounds EXACTLY like a rod knock, but you have a T56, so your converter cant be banging against the flexplate because you dont have one

88 350 tpi formula

iTrader: (9)

often times piston slap can be very bad and does not always go away just off idle. I honestly hear techs who are 30 year plus bla bla bla know a knock when they hear one and I have to tell you your rod bearings are yet again proof you need to properly diagnose an issue and not guess. those bearings look great and I would tend to think even the mains are going to look great too.

a bolt in a cylinder happens alot. some one removes the intake and one finds its way it like iron to a magnet.

a cylinder cancellation test often will tell you what cylinder has a spun bearing. when you take major load off that cylinder it will generally get quieter. (not always but most of the time)

^ same goes for carbon knock^ that goes away though

yes, ran into a/c compressors, water pumps and balancers that made "lower end knocks"



the idea of the valves making noise is a good one too. lots of valve train issues can cause similar issues and I have seen many 5.3 engines to be more specific with wiped out cam lobes

since we have no recording I really cant tell you where to check

DerrenZ

Thanks all.

Yeah, since pulling the pan off, and then the first couple caps, I started thinking I needed to get back to work on a better diagnosis. And I really needed all the feedback from those of you with more experience than myself.

Do I dare hope it still turns out to be nothing more than my shoddy exhaust system? I'll have to start checking everything.

Still, I'm happy to see the bottom end looks pretty good so far.

I'll look into the ARP bolts too.

Summit shows 2 different sets of ARP bolts. Is the correct set based on whether I have 1st design or 2nd design connecting rod bolts?

http://www.summitracing.com/parts/ARP-134-6006/
http://www.summitracing.com/parts/ARP-234-6301/

NBrehm

iTrader: (4)

Theya re the same except the type of metal, one is chromoly the other is plain steel

ghettocruiser

iTrader: (4)

Collapsed lifter maybe? I wish you would have gotten some video of it running...its hard to diagnose from a video, but it might have helped out some.

Some peoples definition of knock can be different from others haha. Did you rotate the motor over by hand and make sure none of the connecting rods were bent and contacting the block or cylinder sleeves or piston skirts? Easy to do now with the bottom exposed.

J.

Mkos1980

iTrader: (8)

I dont know about ARP's bolts but I went with Katech's Rod Bolts and I have no complaints. They are made for using them without rebalancing the setup and so forth.

DerrenZ

The support here at TGO is great, maybe even more than I had hoped. So I hadn't prepared to diagnose it here in this thread, I thought I would just need help getting the lower end fixed.

But yes, I'm back to diagnosis. And no, I don't have much data to work with.

For now, I'll make sure all looks good in the bottom and close it up I guess. Then probably put it back in and work on a more reliable diagnosis. When I heard lower end bearings I was afraid to drive it anywhere or do anything.

Now I'll get more opinions and more info. Thanks to everyone's help, I'll be able to do a better job sorting out my LS1 sounds.

ghettocruiser

iTrader: (4)

LS1's are fairly noisy beasts. Mine sounds like a sewing machine on steriods. The stainless long tubes dont help hush the sound either. At first it bothered me. It sounded bad, made my motor sound unhealthy at the front of the car. Now...if its not ticking...I get worried haha.

But knocking...thats not normal no matter what the engine is. Ticking is ok. Tapping should induce some investigation. Knocking...there's something going on somewhere.

You'll get it... They are still just an engine. Keep poking around and you'll find something.

J.

DerrenZ

Yeah, maybe this will qualify as more of a tapping sound.

So as I pulled my rod caps off to check the bearings, I just cleaned them and put them back on.

Should I have applied any assembly lube in this case?

DerrenZ

Should the connecting rod bolts be replaced either way since they are tty?

Pocket

iTrader: (24)

TTY bolts are not reusable regardless of the application. Ive never heard of a reused rod bolt failure, but they're still not designed to be reused

DerrenZ

I have some 8740 ARP's coming in locally in about 4 hours.

Thanks to the TGO member who offered me a great deal on some of the Pro-Series, but these will be adequate and faster. (I was going to go back with stockers, but the whole TTY stuff changed my mind.)

And is assembly lube necessary if I only pulled the caps to see their condition and then bolted back with the existing bearings? Would be wise, unwise, unnecessary?

Thanks all!

Heritage Z

iTrader: (4)

I would have just put a lite coat of oil on the bearing before installation. Before you put the pan up check crank endplay real quick just to eliminate it.

Pocket

iTrader: (24)

Put some fresh oil in there and bolt it back up. Try not to touch the surface as oils from your skin dont play well with precision steel

DerrenZ

Should I be concerned about resizing the connecting rods when switching to ARP 8740's?

Has anyone successfully switched to ARP's without resizing?

five7kid

iTrader: (14)

Resizing factory rods doesn't work well. Factory rods are "fractured" - the cap is literally broken off of the rod. You can see that the mating surfaces around the bolts are rough rather than machined.

When a rod is resized on the big end, the first thing they do is grind down the mating surface of the cap a little. Can't do that with a fractured rod.

DerrenZ

So ARP recommends this after installing their bolts. Should I not switch to ARP's?

88 350 tpi formula

iTrader: (9)

I haven't seen a failure using the arp bolts on the stock untouched rods. the only way to re-size the ls1 rods is an over sized bearing.

DerrenZ

OEM stock rod bolts should arrive today. These should be adequate since I'm not building or racing the engine, and should be a safe install.

If I want to get the correct torque when I install them, should the threads be dry or oiled?

DerrenZ

Has anyone ever pulled off a cap and replaced it without trouble? Is this an old wives tale that the bolts can only be replaced one at a time, and never take out both at the same time?

I pulled the cap so my bolts are out at the same time. Many instructions say to leave one torqued at all times (one on each con rod).

What could go wrong?

DerrenZ

So I'm now assuming nothing is wrong with the lower end and I'm just trying to bolt it back together without screwing anything up.

I have the new OEM rod bolt shown on the right:



The original one is on the left (ferrule is on the threads).

So for each cap as I replace them:

1. I'm removing the original ferrule.
2. I'm cleaning the back of the bearing and the inside of the cap to remove all traces of oil.
3. I'm cleaning the bearing surface with a soft cloth to make sure I don't have any fingerprints on there and then coating the bearing surface with motor oil (since these are not new bearings, they have 27k on them, I don't think I need assy lube).
4. Finger tight cap onto rod then feel for smooth fit on the outside of each joint.
5. Torque to 15lbs with a loaner snap-on torque wrench.
6. Adding another 75 degrees of turn.

Does anyone see anything I might be doing wrong? I'm mortified I'll screw this up.

DerrenZ

Well, I put it back together yesterday, last night, and this morning.

Here is a 1 minute compact video clip with sound. Yeah, I should have done this in the first place.

The engine is basically cold, fired up once or twice, prolly around 100 degrees.




I don't know what the ticking is... any thoughts?

ghettocruiser

iTrader: (4)

I would not consider that a knock.... Obviously it might sound different in person, but it doesnt sound "deep" enough to be bottom end from the video (which backs up your findings when you pulled it apart).

That almost sounds like a lifter is stuck.

You dont have any major exhaust leaks (not sure how your exhaust is set up) or spark plugs that arent seated all the way do you?

Someone else might chime in...but that kinda sounds valve train related.

J.

Mkos1980

iTrader: (8)

I'm with ghetto. Its valvetrain. Check for a bent pushrod. That would cause a ticking lifter.

DerrenZ

You know when I took it the guys with more LS1 experience, I was expecting them to say valvetrain or exhaust. They said it was not valvetrain. I thought it was a good thing I took it to someone with experience.

And when they said bottom end, I nursed it home and opened it up. Maybe I snugged up the exhaust better this time. I think it is more clear now that it's not a deep sound and seems to be coming from up top.

In fairness to the guys at the shop, I didn't ask for anything but their quick and dirty, come out for free and give it a listen opinion. So I'm completely happy that they took the time. And better safe than sorry.

I don't feel quite as nervous driving it now while I track it down.

Sure sounds like valvetrain to me too. If it was a SBC I'd say it was an obvious lifter tick. I know what that sounds like.

Not knowing LS1's it's good to hear you guys say valvetrain, since you have actual LS1 experience.

Thanks much guys!

Heritage Z

iTrader: (4)

You don't want to touch the bearings dry, but if your just smearing fresh oil over the bearing your fine. Kind of a wives tale.........

ternandes

iTrader: (7)

Sounds a lot like valve train to me as well.

ghettocruiser

iTrader: (4)

Very first thing Ide do at this point... Pull the valve covers, and check things out. See if there are any obviously loose pushrods with slack in them. Or any obvious signs of rocker issues. Also check to make sure none of the springs look broken or shorter than the rest or anything.

Then, Ide pull all of the pushrods, and roll them on some glass. A mirror or window or something...anything perfectly flat. See if you have any bent pushrods.

If you dont, then Ide be looking at lifters I guess...

J.

DartByU

Are all the cylinders hitting well as in if you pull a plug wire you get a solid miss show up, have you done a compression test? If all that passes then it may be a bent push rod, I would just drive it easy for awhile and the ticking may go away, I fixed an old engine with ticking valves once by running 2 quarts of automatic trans fluid in it for awhile, AFT fluid has lots of detergents in it that clean really well.

DerrenZ

Thanks for the pointers guys!

I'll start tracking it down today or tomorrow hopefully. The family demands some attention since I've been hiding in the garage for the last week.

DerrenZ

I pulled both valve covers to look for anything amiss. Everything looks fine. I couldn't find any loose rockers or pushrods.

I have taken the rockers and pushrods out of the driver's side and so far everything looks fine, nothing bent. The noise seemed to favor the driver's side, though earlier it seemed to favor the passenger. If I stand right in front of the car it seems like both sides.

I will pull the passenger rockers off next.

I'm thinking maybe lifters. But if a lifter was bad, wouldn't I have found a loose pushrod/rocker assembly somewhere?

ternandes

iTrader: (7)

You could have a lifter that isn't pumping up (collapsed) and you would get a tick.

DerrenZ

Wouldn't that tick be caused by play, or slop, between the rocker arm and pushrod as a result of the fact that the lifter is not fully extended?

Would I have expected to find a loose rocker/pushrod if a lifter wasn't pumping up? Or is it only noticeable when the engine is running?

Perhaps everything is tight when the engine is static, but a bad lifter only causes noise when everything is moving?

If that's the case, then I can keep suspecting lifter. If a bad lifter is evident from loose components in the pushrod/rocker arm assy upon pulling the valve cover, I will have to come up with a new theory.

DerrenZ

Is it possible to have a bad lifter without seeing any slack in the valvetrain?

Is it possible to have a bad lifter with no apparent damage to pushrods or rockers?

So far I don't see any slop, loose rods, or damage, but I'm thinking about just pulling the heads and replacing all the lifters.

Good idea?

Mkos1980

iTrader: (8)

can u start it without the valve covers like a gen 1 sbc and check for play?

DerrenZ

I don't know. It would be very messy at the least since the coil packs mount to the valve covers. They would have to dangle in the vicinity of the oil spray...

I guess I'd like to hear if anyone has done this with an LS1, it may help me diagnose my noise.

ternandes

iTrader: (7)

Yes, if you have a bad lifter, you can have zero lash with the engine not running, and still get a tick because the lifter is supposed to pump up with oil. If it doesn't, you will get the tick.

DerrenZ

Well I've ordered a set of LS7 lifters and trays. Let me see if I understand this. If a lifter "collapsed" then I would find a loose pushrod at that lifter. But if it is just a matter of not pumping up during use, it will only be noticeable when the engine is running?

So if my problem is a lifter not pumping up, will I be able to tell what lifters are bad when I pull them out?

Mkos1980

iTrader: (8)

Hope you ordered new headgaskets too!

DerrenZ

Yes I did. And just as important I ordered new head bolts as well.

But again, will I be able to spot a bad lifter if it was just failing to pump up during use?

kevinc

I just did a top-end teardown on mine this Spring for a very similar noise and never found a definitive cause. No wiped cam lobe, no visibly damaged lifters, no bent pushrods, etc. The lifter plungers wouldn't budge when pushed manually w/ an old pushrod, either.

In went new Morel lifters, new LS6 cam, new PAC 1218 springs, new GM rockers...no more noise. Didn't have time to conduct repeated teardowns for incremental parts replacement so I threw the whole parts bin at it to ensure a clean kill on the problem.

It bothers me that there was no "smoking gun" in there to be found, but it's fixed.

My big change going foward is no more API SM or SN spec oil. More detergent, less zinc & phosphorous anti-wear additives. No thanks.

DerrenZ

So what oil are you going to use now kevinc?

DerrenZ

What do I need to know when installing new lifters? I've heard to soak them overnight in clean oil, and to try to actuate the mechanism to help fill them with oil, but is there anything else I need to know or do?

I am also replacing the lifter guides.

mw66nova

iTrader: (13)

roller tip goes on the camshaft.

lol, jk...there is no real procedure. most lsx engine build books say not to worry about soaking them in oil. i did, but only because i did it before i read the books. i also pu all the oiling holes towards the front of the engine. not because they need to be, but because it was all uniform that way.

DerrenZ

Thank you sir for the reply.

Yeah, it kinda seemed to me that if there was air somewhere within the lifter that it wouldn't matter how many hours it sat there under oil, the air wouldn't move. Unless you were agitating or rotating it somehow.

But everyone says to do it that way.

This is why I sometimes feel compelled to ask straight up dumb questions. I "use the search feature" but often times an idea can be repeated in thread after thread and still be wrong.

So roller tip toward the cam you say...

Thanks!

EDIT:
For anyone in the future stumbling across my silly questions looking for an answer, I just found this post that expands on what Matt said:
http://www.hotrodders.com/forum/prim...ne-114580.html

DerrenZ

Pull driver's head tonight. Cylinder #7:





Sigh...

I've never broken a piston before. What can cause this??

ternandes

iTrader: (7)

Extreme detonation. What made you decide to pull the head?

Pocket

iTrader: (24)

Aww thats terrible

Rotate the piston to BDC and see if there are any scratches in the cyl wall you can catch a fingernail on. Check the cyl head and see if either of the valves are nicked from chomping on the piece as it made its exit

Id also call up the place you got the engine from and see if its under warranty still

Best case scenario a new piston/rod off ebay and you're back in business. Worst case, the cyl wall is gouged too far and the block has to be replaced. Cyl head may need a valve job if it chomped on the piston pieces assuming the chamber isnt hammered beyond recognition