Cross Post - Another "what's this noise" thread
 

** Please see post 7 after this, I've updated with new testing results***

I started this in the engine rebuild forum because I'm afraid that's where it's leading. It was suggested I cross-post here to get the attention of some of the masters. For reference, not in my initial post:

1975 911 with a 78 (iirc) 3.0. Oil level is good (in the middle of the stick after warm), oil pressure is 30 on the gauge, warm temps never get above 200-220.

I purchased it a couple of years ago, had been sitting a while, failed restoration. I got it running and have driven it 1-3 times/week since until the last month or so. Totally unknown engine history. I've probably put 7-8k miles on it, have changed the oil 3 times, last about 6 months ago and at that time tried to adjust the valves and discovered I couldn't get the right valve cover off due to hitting the aftermarket header that's on the car.

Ok, videos:

Initial Start - Cold:
<iframe width="640" height="480" src="https://www.youtube.com/embed/36kPfznsTIU?rel=0" frameborder="0" allowfullscreen></iframe>

Taken when warm:
<iframe width="640" height="480" src="https://www.youtube.com/embed/epPHfxll98E?rel=0" frameborder="0" allowfullscreen></iframe>


It seems my new "knock" comes on strong after a few seconds, it's steady with RPM, seems to be coming from the middle of the motor. There is a "tick" that I have undoubtedly identified to the middle right (5?!) cylinder with the long screwdriver method. All others are relatively quiet. I can't identify the exact location of my knock with the screwdriver.

Pictures:

This is the "diaper" under my car, haven't driven it in 3 weeks at all, as you can see it's not leaking but a drop here and there. She has never in my time consumed any oil to speak of:
http://forums.pelicanparts.com/uploa...1344098542.jpg

Right Bank - shows my clearance issue w/ the header:
http://forums.pelicanparts.com/uploa...1344098683.jpg

Right side showing cam cover:
http://forums.pelicanparts.com/uploa...1344098718.jpg

Bottom of the engine:
http://forums.pelicanparts.com/uploa...1344098773.jpg

Left Bank - this side clears the header
http://forums.pelicanparts.com/uploa...1344098833.jpg

Left Cam:
http://forums.pelicanparts.com/uploa...1344098888.jpg

Valve clearance issue to much gap.

The right-side ‘tick’ is probably valve related. Take the covers off and check the valve clearance, inspect for rocker arm shaft sliding out and inspect for broken valve spring.

The center ‘knock’ is worrisome.
Drain the oil through the sump plate drain plug into a clean container and then carefully remove the sump plate. (Don’t drain the oil by loosening the sump plate.)
Inspect the sump plate for ‘gold color’ debris (flakes).
You want to inspect the small area between the sump screen and the crankcase opening, particularly where the screen is attached to the flat housing.

Drain the oil filter and cut apart (there is a special ‘can-opener’ tool for this job at most shops.
Spread the paper element out linearly.
Using laquer thinner, clean the filter element by washing through the filter, leaving the debris in place.
Again, inspect for debris.
Please post images of anything you find.

Best,
Grady

Thank you, I ordered a leakdown tester this morning, had planned to try and do a leakdown & compression test before I drained the oil, I'm assuming it's time to drop this engine for several reasons and wanted data to report before I started opening things up.

Is this too much of a risk at this point? I've only driven the car twice since I started hearing this new knock.

Travis

To me, that sounds valve related, but not sure what a main bearing knock would sound like in a flat-6. It doesnt sound like a rod bearing because those double knock.

Checking valve lash should tell you pretty quick if it's bearing or valvetrain related IMO.

Yeah the center knock sounds like a wrist pin. You should get turbo valve covers for the bottom.

Updating
 

I humbly [re]summon the 3-liter whisperers...... apologies for the delay, I've had weeks of pummeling work and started my ~40 y/o a$$ self back to college. Please prepare for an onslaught of data, I really really appreciate your feedback.

So I spent most of today doing a full boat of tests suggested above here are the results:

First.....What engine do I have? 6383878 - I've triple checked it, looking in Zimmerman's book the 2nd digit makes no sense but otherwise seems the '78 3.0 I thought it was.

Spark Plugs:

http://forums.pelicanparts.com/uploa...1345946954.jpg

All black in color, I am fairly sure I've been running it rich, not any wetness when I pulled them out

Leakdown Test:

Ran my compressor at 110psi, adjusted the left dial to 100psi, each cylinder showed ~98-99% and never moved. Every single cylinder held 2% loss or less, left each one ~5 minutes.

This is good news right? Is it possible I botched the test? I did at one point play with it off the car and was able to see it drop and swing up and down as I capped the pressure off with my finger so?!

Compression Test:

Cyl 1: 150 psi
Cyl 2: 148 psi
Cyl 3: 150 psi
Cyl 4: 98 psi
Cyl 5: 125 psi
Cyl 6: 145 psi

Remember my issue earlier with not being able to adjust the lower valves on the right side. Hoping that is the source of my odd compression #'s on that bank?!

Oil Drain/investigation:

- First off, whoever suggested straining it through the old white t-shirt, not cool dude! - (maybe I prefer too thick t-shirts )

http://forums.pelicanparts.com/uploa...1345947638.jpg

Drain plug, screen and plate-

http://forums.pelicanparts.com/uploa...1345947680.jpg

http://forums.pelicanparts.com/uploa...1345947711.jpg

http://forums.pelicanparts.com/uploa...1345947734.jpg

as you can see, clean

Ok, here's the fun part:

http://forums.pelicanparts.com/uploa...1345947823.jpg

http://forums.pelicanparts.com/uploa...1345947844.jpg

http://forums.pelicanparts.com/uploa...1345947862.jpg

http://forums.pelicanparts.com/uploa...1345947889.jpg

So what the hell is that half a ring that dropped out? On the good side I could find no real shards otherwise, no flakes of metal, what's on my fingers I believe to be carbon? I found 1 goldish flake in the t-shirt. The oil that came out of the sump was the same, found no more pieces, see below the plug, had sludge but no flakes.

http://forums.pelicanparts.com/uploa...1345948066.jpg

So there's the investigation, I open it up to the world.

Sometime in the next couple of weeks the engine is coming down so I can address whatever is going on including the valve adjusting problem. What am I looking at here?

Thank you, Travis

Is that piece magnetic? Looks like a broken valve spring probably on # 4 cylinder.

I dunno, but I'll check tonight

99.9% sure thats a piece of broken valve spring! Although it looks hollow, so don't know for sure if valve springs are/were hollow, or if that's just a anomaly from the picture... Magnetic test will tell you the answer.

IMHO, The sludge you show pictured on the rag next to the magnetic drain plug is fine metal debris most likely from your bearings. That's a lot of bearing wear. If it builds up like that between oil changes that would be very worrisome to me and almost certainly dictate a bottom end rebuild.


Good luck and keep this thread updated as thee are several Pelicans doing similar diagnosis on sounds coming from their engines...

Must be a picture anomaly, it's definitely not hollow. Are the springs magnetic?

There was none of this on my engine plug, and the oil wasn't sparkly. IIRC I had quite a bit of this my first oil change after the engine had been sitting for several years. - still think bearing wear?


Thanks, I will keep updating as progress continues until she is back pounding the pavement. If this really is a valve spring can I hope there's a possiblity of getting out of this w/o having to open up the case?

Others have successfully changed valve springs without tearing the engine apart. Compressed air is your friend. Do a search, I've seen a few threads about it.

The piece doesn't appear to be magnetic (didn't pick up any of the nuts or bolts lying on my workbench).

Read a bunch of threads on spring replacement yesterday and those pictures certainly do look like mine. I did notice more "spiral" in the shard than I'd seen this weekend.

So could a broken spring cause the knock I have? Valve bumping the piston? All conjecture until I drop the motor and find out more?

sobamaflyer,

Please post more images of the broken part.
It appears to be round at one end and flattened at the other.
If so, this has the profile of the end coil of a valve spring (probably an inner spring judging by the diameter).

OE valve springs should stick to a magnet. I suppose some aftermarket springs (stainless, titanium) would not stick.

If this is a piece of a valve spring, this may be the ‘tic’ at your #5 cylinder.
You can inspect this in the car by removing the #5 rocker arm (intake first) and inspecting the valve springs.
There are valve spring compression tools (different for intake & exhaust) that will allow you to replace springs in the car.

It would be very unusual (almost impossible) for the broken piece to have caused any distress in the ‘bottom end’ of the engine.
The ‘center noise’ is probably a separate issue.


I’m concerned about the low cranking compression on #4 cylinder.
The ‘good news’ is it didn’t show on the cylinder leak.
That would lead me to suspect the tests.
I would repeat both tests.


Was the ‘fuzz’ on the drain plug magnet accumulation over only a few miles since the last oil change and magnet cleaning?
If so, inspect all the cam lobes and rocker rub-pads.
The material is obviously magnetic.
Cams and rockers are magnetic, babbit bearing material is not.
Check (measure, not reset) the valve clearances.
If the cam lobes & rockers had been rusty from the sitting, they (one or all) may now have high wear having breached the hardened surfaces.


Get yourself an automotive stethoscope from a local auto parts store.
From under the running engine, see if you can better locate the center ‘knock’.
Use the stethoscope probe on the cylinders.
Also see if there is a fore-aft difference.

If the piston were hitting the valve (due to broken inner spring), it probably would bend the valve and show as a cylinder leak.


Best,
Grady

http://forums.pelicanparts.com/uploa...1346188669.jpg

http://forums.pelicanparts.com/uploa...1346188687.jpg

- It stuck nicely to a magnet

- crap


- can I repeat those 2 tests on a cold engine?


- I last changed my oil the end of last year, maybe 2-3K miles ago


- 10-4



Best,
Grady - Thank you!

So I started my first 911 engine removal this morning.

I've read a couple dozen threads over the last few weeks on this subject and don't really want to start another so I'll question here.

Why is it that half I read says take the engine and tranny out as a unit and half the pictures I see show the tranny left in?

So far I've disconnected everything but a stubborn fuel return connection and continue soaking my left engine bracket bolt as even my impact wrench isn't wanting to budge it. (To take only the engine out). Part of me doesn't feel like disconnecting all the tranny apparatus and part of me says take it all down and use this as a cleaning/refresh under there opportunity. I've even got the 3 attachment bolts out, still need to fight with the 10mm allen.

Pull the transmission with the engine.
This is a much ‘cleaner’ R&R. Particularly going back together.
Flat-rate mechanics just pull the engine and charge for both.

Yes, that is a piece of valve spring.
Why coming out?
What did you find?
Replacing a valve spring can be done with the engine in-situ.

And yes. You can do cranking compression test and cylinder leak test on a cold engine.
The ‘fuzz’ accumulation over 2-3K mi. is not all that unusual, particularly given the sitting history.
Cut apart the oil filter.

Best,
Grady

Make sure the battery is disconnected.
I personally find it easier to remove the engine and transmission at the same time. Separating them on the ground and mating it back together is simpler when they are sitting on 2 dollies than when laying on my back under the car. Trying to reach the top bolts, or getting the release fork on the throwout bearing.
Once you get the center of gravity they, come down nicely together. Besides, you may want to change some seals on the transmission while your in there. Disconnecting the transmission linkage is easy enough. Disconnecting the wires from the starter is not much either. Maybe check the CV joints. Gives you a chance to inspect the brake lines easier also. Might as well make sure evrything is in good shape now so you don't have to drop it again later.

I've been wanting to take the engine out since I bought the car to perform a really good cleaning and replace the sound mat but I enjoy driving it too much and have too little time so I've yet to do it. I have known it means probably months of the car being down.

I had gathered 1 problem was nailed down to a valve spring and had read it could be done in the car, but your prior warnings and fears about my newer knock not sounding like it could be related has me scared to grenade what is otherwise seeming like a healthy engine.

Is your advice then to proceed a little further before dropping it? Try to get the header off the Right bank in the car so I can properly access that valve cover and address the spring issue and new valve adjustment? Am I being counter productive spending the effort to take it out at the moment?

I haven't yet gotten the stethescope you suggested and I have been going back and forth this week as to whether I needed to fill it back up with oil to do more tests, and not sure I can hear the knock during cranking or just running?

I'd love nothing more than to think I could fix this [relatively] little issue, oil it back up and return to my couple times /week of 911 stress relief.

Sorry … I have to laugh (politely).
You want to take the engine out (for several reasons).
Yes, go for it, with the transmission also.
You will enjoy the process.
Just make sure you get it back together asap for your ‘911 fix’.

Replacing the valve spring is simply easier on an engine stand compared to in the car. The process and tools are the same.
Difficult is that you can’t then run the engine and tell if the “central noise” has gone away.
I’m not convinced that they could or could-not be the same.
I’m a proponent of repairing the valve spring in the car and only then, if necessary or desired, pulling the engine & trans.

In the process, get rid of the exhaust that precludes you removing the lower valve covers. There are better options.

Best,
Grady

I laugh whole heartedly at myself on a regular basis, please feel free :)

for personal growth....which part was the chuckle for (the time out, the haven't yet or the taking it out for what should be a simple repair?) I happily admit the downtime is excessive, I have a 3 year old, a wife that appreciates attention, a stressful job and most recently a return to college. All take away from any real garage therapy time but are more important in my grand scheme (and I don't have funds to drop my toy off to be fixed for me).

I'll take your advice and drop that header before I go further and see what I see, gotta be fixed anyway right?

If I get out of this w/o a rebuild I'll have a good excuse and funds to do something about my [somewhat] bobo exhaust. I would kinda like to have a stock set of HEs and a non-Flowmaster (although I've grown to somewhat enjoy it)

“Simple repair” – no such thing.
It always turns into “while-you-are-there”.

I’m a strong proponent of diagnosis and planning.
I like to think-through a few steps farther along any situation.

In your situation, it is easy to say “time for rebuild”.
That may not be necessary.
Yes, it may be what you (secretly) want.
If so, buy another engine and keep your 911 functioning.


3-YO, I’m jealous. In spite of the stress, I miss it at 70+.
I make-up tutoring/mentoring an 8-YO tomorrow. I hope to live to attend Nathan’s PhD dissertation.

Best,
Grady

"Secretly want the rebuild".....sure the allure of breaking this down and KNOWING what's in there that remains a question mark a couple years of wonderful, enjoyable ownership....... I'm not afraid of it, I've rebuilt a couple of VW motors w/ success. But the reality is I "shouldn't" if I can at all avoid it, I have too many other places to spend $.

I love my little family, I love that I'm passing along to my son the love of these old greasy things. I can't be out in the garage working on anything without him climbing on top of me/it wanting to know what he can do. He's getting good at finding me the 10/13/15mm wrench lately.

I'll report back with new data with any luck tomorrow morning.

Morning report, right bank open....

Engine is close to TDC on #1 - I have noticeable (but not awful) valve looseness on #6 exhaust, and #5 intake. There is NO play in any other tappet, I CANNOT budge any of the 6 valves (springs) by hand.

I didn't have time to go ahead and dig into the left bank to see if I found the same there.

Did I need to rotate the engine to feel the spring play I've read about in other "broken spring" posts?

Intake:

http://forums.pelicanparts.com/uploa...1346686475.jpg

http://forums.pelicanparts.com/uploa...1346686487.jpg


Exhaust:

http://forums.pelicanparts.com/uploa...1346686529.jpg

http://forums.pelicanparts.com/uploa...1346686552.jpg

http://forums.pelicanparts.com/uploa...1346686584.jpg

Inside of Valve covers - There was a small amount of debris but as before I didn't really find any flaking or metallic stuff, just a bit of crud


http://forums.pelicanparts.com/uploa...1346686676.jpg


http://forums.pelicanparts.com/uploa...1346686691.jpg

Exhaust and Headers
 

correct me if I'm sorely mistaken but I've always taken these for fairly decent stainless headers, they are dirty but they do polish up

I've got mixed feelings about the Flowmaster, it may need to go regardless and today's lesson was that it wasn't too awful lowering that header to get access for a valve adjust

http://forums.pelicanparts.com/uploa...1346686794.jpg

And one of my sad state car:


http://forums.pelicanparts.com/uploa...1346686828.jpg

Very confused - I took the left bank covers off this morning and found more of the same from last week. I cant really budge any spring using a screwdriver while carefully studying each w/ a mirror and light. They all "look" normal.

Makes me wonder if it's a break I just can't find or a past repair I'm just now finding a piece of?

Any suggestions to my next step?

“Very confused” yes

I would guess there is a high level of probability that the piece of valve spring may be from some previous incident.
That said, I would not discount there is currently a broken spring.
It may be that you will want to disassemble and reassemble each valve spring in-situ.
This is a pita and may not yield anything other than the confidence there isn’t a continuing issue.
Your only cost are the two valve spring compression tools (easily resold later).

Diagnosing and devising a correct course of action are difficult when you don’t have all the historical information.
You don’t know what PO or some hamburger mechanic may have done over the past 37 years (and there have been a lot of opportunity).
This brings up a difficult decision faced by many owners and not just limited to our ‘old’ 911s.
This is one reason many completely ‘rebuild’ a fine old 911 – to insure you know every detail of its condition.
I’m not suggesting this in your case, just making an observation.


So … what to do?

I think you have some ‘soul-searching’ decisions to make.
These are probably common to many (most?) mid-year 911 owners.

First, I would objectively analyze the condition (rust, prior crash damage repair and overall) of your 911.
Unless you are committed to this car (your dad’s first Porsche?), you should consider the cost of investment in repair compared to the resale value.
We all ‘love’ our Porsches but reality must take some position.

I think the investigation of the valve springs may be a ’pain’ in terms of effort but may confirm (or not) the issue with only your investment in time and effort.
The cost of the two tools (and eventual resale) are insignificant.

All this keeps in mind that there may be other issues (noted above) like wrist-pin bushings, broken piston rings, head studs and more.
Your 3-liter engine is very robust compared to the original 2.7.
That doesn’t mean it doesn’t have issues needing repair.

I’m a long-time proponent of fixing things right – given the 30+year experience, repairs can be better than original.
You can have a nice 911 far better than Porsche built it originally (rust and prior crash excepted).

Decisions….

Best,
Grady

To date I'm into this car for ~$8k (purchase and 2 years of parts replacements/additions), it has no historical or sentimental value other than being my first 911 after having dreamed of having one for 25 years prior. It's rather Franken-porsche-ish being a mish-mash of parts (but I am very fond of it's state in general)

I have no illusions that it's really worth a lot more (running) than I have in it now. This is my main hobby, I don't golf, fish, hunt, go to football games so cars are a place I choose to "waste" $. I accept that at some point I'll have far more in the car than I could ever sell it for. And I've at least had the idea pass through my head of trying to sell it running and get another ~10-12k 911 but I keep coming to the conclusion that I'd just be re-starting with a new set of unknowns (given my req'd price range).

That said......

I need to get and will get the spring compressors so that will happen this week.

If I check out each spring, even if I find 1 broken and replace it and put it back together. Do I hook everything back up and try again for a harder ID on the new knock in the middle (hoping/assuming I've addressed the "tick" with springs and valve adjustment.

Or am I bandaiding and would be better off to go ahead and open this up?

Sounds like you have a decision to make...
If it were me, I'd get Wayne's engine rebuilding book, determine the parts and tools needed to do the work, make a plan and do it right.

Check, got it a few weeks ago and read through most of it.

I've been stalling I guess hoping the magic Porsche fairy would show me a loose nut and put me back on the road

Sent from my SCH-I535 using Tapatalk 2

I'm well down the rabbit hole trying to diagnose my errant noises.

http://forums.pelicanparts.com/uploa...1348664537.jpg

My wife and son have been out of town for several days so I've had actual time to tinker. I broke my engine mount cross-member at the left weld (hoping to catch one in the classifieds). My first 911 engine drop went surprisingly smooth otherwise (after I figured out I'd not unhooked the clutch cable & then reverse lights).

I am waiting on a PP order to get spring compressors & cam tools. I haven't found anything really disturbing so far, knocked the biggest chunk of grime off right after I pulled it. I have 4 header studs that came out but visual inspection inside the valve covers so far doesn't cry out anything crazy and the head studs all "appear" intact (I'll confirm that for sure soon).

Obligatory "dude in an engine bay" photo:

http://forums.pelicanparts.com/uploa...1348665136.jpg

Not bad for not having a soul around to lend an extra set of hands.

Made a little more progress today (a little)

I have the top stripped down, chain covers off, cam nuts are both loose.

I continue to feel like this engine was rebuilt not terribly long before it was put away, everything inside is relatively spotless, seals are all fairly fresh.

I don't seem to have Carrera tensioners but they look odd (anodized collars on the top?), any hints as to why they look different than what I've seen in pictures?

I have the valve spring compressors on-hand but have yet to delve into exactly how to use them. I'm continuing to follow the book so...

http://forums.pelicanparts.com/uploa...1349220629.jpg


http://forums.pelicanparts.com/uploa...1349220640.jpg

submitted for evaluation & advice
 

I'm looking for those in the know to comment on what I've found so far.

Clutch:
I'm in need of a new disc? Resurface the mating surface or can I clean it w/ a scotchbrite pad?
http://forums.pelicanparts.com/uploa...1350237312.jpg

http://forums.pelicanparts.com/uploa...1350237445.jpg

Cylinders:
All look like this, some carbon buildup on the crowns but the cylinders seem to be in nice smooth shape. Given my good leakdown and compression numbers I'm thinking about removing the pistons & cylinders as a unit (as described in the book). Not messing with them/the rings?

http://forums.pelicanparts.com/uploa...1350237711.jpg

http://forums.pelicanparts.com/uploa...1350237744.jpg

Heads:
Also (aside from dirty) appear to my untrained eye in decent shape (I may be corrected in this) the valves appear to seat but I need to look into this further. I also still need to take off the valve springs to check them and see if one is broken. I foolishly bought the 2 seperate tools when I needed the 1 big c-clamp one.
http://forums.pelicanparts.com/uploa...1350237800.jpg

Studs:
I'm thrilled! Every single dad-blame nut came off without incident. Hoping someone can tell me what is here, they are not magnetic, they are black and slimmer in the middle than the threads.
http://forums.pelicanparts.com/uploa...1350238073.jpg

I continue to hypothesize that this engine was rebuilt some time before it sat for at least a few years. I have no basis for judgement of the quality of the rebuild, what was done, what wasn't. I highly doubt this is a stock, original '78 3.0.

I still have a way to go, I plan to at least get all the way inside to find out if there is a bearing messed up causing that knock. (I will be at a loss if I find nothing amiss as I have so far)

Thoughts, opinions, tips, hold on moron what are you doing??(s)

Thanks, Travis

Looks like you are really digging in.
Here are some answers, personal opinions and questions for you:

Here is a link to the chain tensioner collars you have. :Pelican Parts - Product Information: 99-0458-053-M230

Is there any lateral play in your rockers on the shaft when they are not on the valve(loose) ie: can you rock them at all from left to right?
I'm wondering if the rockers weren't rebuilt or were mixed up when assembled.
If they aren't worn with the cam they will be noisy.

Measure the thickness and if more than 50% worn, replace the clutch and have the flyweel resurfaced so you don't have to go back in there in a year....

Head studs look like the Canyon ones but if not magnetic at all then perhaps the updated Dilivar.
Pelican Parts - Product Information: 10-0115-101-M105
Pelican Parts - Product Information: 993-101-170-53-M260

I bought this spring compressor for my OHC Toyota, I'm sure it would work for you.
Heavy Duty Motorcycle & Car Valve Spring Compressor Kit SET | eBay

Thanks Dennis,

I agree, the studs do look like the Canyon ones. I had come across the collars last week after asking, and also read about them in the book while re-reading that section. I'm afraid a tensioner upgrade is not in the cards at the moment so I hope they are ok for a while.

Given how close some of the little rivets are to the surface I have to believe that clutch disc is almost gone but I haven't measured it to truly compare. It's going to be on the shopping list.

So confused
 

I really thought I'd find something significant at this point......

Trying to capture the amount of play I found on the rods. This is indicative of all 8, I can wiggle them side to side less than a mm.

<object width="853" height="480"><param name="movie" value="http://www.youtube.com/v/CBD1W0WxpHo?version=3&amp;hl=en_US&amp;rel=0"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/CBD1W0WxpHo?version=3&amp;hl=en_US&amp;rel=0" type="application/x-shockwave-flash" width="853" height="480" allowscriptaccess="always" allowfullscreen="true"></embed></object>

(pardon my shop helper in the background)

Pistons:
All look exactly the same, all rings visually appear clean, solid, ok. Surfacing is clean, mar free.

http://forums.pelicanparts.com/uploa...1350429870.jpg

http://forums.pelicanparts.com/uploa...1350429881.jpg

http://forums.pelicanparts.com/uploa...1350429895.jpg


http://forums.pelicanparts.com/uploa...1350430057.jpg

http://forums.pelicanparts.com/uploa...1350430075.jpg

http://forums.pelicanparts.com/uploa...1350430087.jpg


Dennis, I tested my rocker arms for play, when off the cam I can wiggle them maybe 0.25mm back and forth (all of them)

So where do I stand? Do I keep going since I'm this far? Do I finish taking it apart the case? Shouldn't a failed bearing have presented itself at this point? Or maybe that was never the cause of my disturbing knocking (and if not what was?)

Hoping someone will tell me check this or that or notice anything good or bad in my photos. I'm in too far to just put this back together without ensuring (to some measure) that I will get some significant mileage out of her before doing this again, but I also don't want to waste $ if it is fine.

Without being there to inspect, feel, mic and measure it's hard to say!
I'm thinking you should proceed with the valve train disassembly. Most of your noise in your first post seemed valve related.
See how tight the rockers fit to the shafts once removed, (don't mix them up) check/Measure the bore of the arm, inspect the wear on the rockers, the shafts and the camshafts. Any pitting or heavy wear?
Then once you have your compression tool check the valve springs, seats, seals etc.
Did you measure your rocker arm clearances on disassembly?

The heads at the moment are still fully assembled. I may have misunderstood what you suggested? I merely managed to wiggle some back and forth and could wiggle others similarly if I rotated the camshaft.

The camshaft itself is not pitted or scored at all, polished and shiny.

sent from my Galaxy S III

you should be able to identify excessive rod play by just push and pull. you cant tell much from rocking them back and forth. atleast thats been my experience from rebuilding vw and briggs engines

I was referring to play on the rocker shafts. if they aren't at a close tolerance on the shaft they can wander, bounce and rattle.
Try a torque wrench on the rocker shaft nuts set at 8 ft lbs and see if they are tight.
Should be tighter according to most builders. Around double that amount on an old engine.
I'm just looking for a source for the noise.

My camshafts looked great when assembled.... replaced both due to pitting on 3 lobe tips.

http://forums.pelicanparts.com/uploa...1350441741.jpg

My workbench last fall:
http://forums.pelicanparts.com/uploa...1350441824.jpg