drivers side
 

the drivers side tensioner does not look like it is extended much at all.
is the chain tight?
can you leverage the ternsioner upwards to make the chain tighter easily?

Chains are tight, I'll try cranking it and observe what happens. Checking the basics: so far its spinning the fan/alternator with no belt; removing rocker covers on the right ride and checking everything there; checking for exhaust leaks. I guess I could pull the left side covers, but the noise was very clear on the right and not audible on the left using the screwdriver listening test. How do I check the distributor shaft for play?


Chains and ramps were replaced 4k miles ago so they are basically new (see my original post with parts list.) Ramps look spotless, with the raised "tracks" clearly visible. I have no idea how far these should be extended?


Chains seem tight to me, I can't get them to move much at all (either just the chain or by leveraging the tensioner.) I was able to compress the tensioner on the left side by less then 1mm, the right side won't compress at all.

I am sorry i can not go back and read 5 pages, just trying to help.
Did this noise come on just recently ? ( I would guess)
Can you take a mirror and look inside and see if ALL the chain is on ALL the sprocket ? (not halve off )

Noise was noted on PPI, that was at 2k miles after rebuild. I've driven it 2k since then and the noise has not changed. Finally decided to investigate. Some new parts in the motor, lots (bottom end) that has seen 160k miles.

Chains are seated properly on the sprockets- you mentioned that the other day so I was sure to check.

Rebuild was done by a pro shop, but the PO ordered the bare minimum overhaul so I'm dealing with that...

If you have gone 2000 miles ( with no change ) it must be not as big emergency as I once thought.
When you roll the engine over, the chain and sprockets must look all ok?
Perhaps recheck the exhaust system,........... i am sure you have.
But it is coming from somewhere that bothers you.

I made a little video showing the tightness of the chains. Squeezing the chains like this I can't get the tensioners to compress more then 1mm in. The left side tensioner is further in then on the right side, but still pretty far out. The left side chain has more slack the the other side as well, the right side is really tight, left doesn't seem bad though I can force it to make a clackety noise as you see in the video..

The only other thing I discovered is that the idlers have a fair bit of space to move side to side on their shafts, I assume this is by design to help the chains and ramps stay aligned with each other.

As previously mentioned everything in these boxes looks pristine. I may just close them back up.

<iframe width="560" height="315" src="//www.youtube.com/embed/jGoC11DyxeU" frameborder="0" allowfullscreen></iframe>

Your starboard tensioner seems to leak oil and collapse out when you put pressure on the chain..
I am not at all sure how long they should hold static hydraulic residual , but it looks suspicious .

Pressure-fed tensioners are like hydraulic lifters. Engine oil pressure constantly replenishes oil that bleeds out from the tensioner. While the piston rod is slightly extended but still firm, it looks okay.

The acid test is to run the engine w/o the china box covers and observe the chain at various engine speeds (e.g. idle to 2000 rpm). Sure, oil will be thrown and w/o a muffler, a little noisy, but it's only for a little while. Purchase some pastry for the neighbors. Lights, camera, action.

If the above is okay, button it up. Don't remember if this was already suggested, but with the engine at rattling rpm, short out each cylinder in turn (disconnect spark plug wire) and see if noise diminishes.

Sherwood

So, tonight I put everything back together and filled the engine with oil. Went for a nice long drive, topped up oil level hot, and then tried pulling one plug wire at a time to see if the clack changed. Same result all the way around: there was much more clack noise running on 5 cylinders regardless of which plug wire was removed! Clack at idle is much less audible then oil-cap-removed slow idle, then I really hear it. Leaning towards just running this engine as-is another season... :cool:

I would too

try putting a screwdriver on each cylinder (with rear of car raised), then on each head. See if it isolates itself to one piece. I have had this type of noise go away all on its own before.
Alan

Will do, I'll get it on the lift and do some serious listening. Is a stethoscope worth getting too?

Also, is there any harm idling the motor for longer periods (say 15 minutes) with the oil cap off? I still read just over 1 bar oil pressure on the gauge in no-cap-slow-idle mode, but it does make me nervous.

You don't really need a lift, nice but not really needed. Just jack the rear of the car up, put jack stands under the torsion bar ends, and lay under it. Screw driver is just as good as stethoscope for this. Place the blade end on the cylinders, then on the heads. I am quite sure you will isolate it. It should only take 5 minutes. (Been there, done that).
1 bar pressure is plenty at idle. For long periods you just need to watch the oil temp. But no need really to run it for 15 minutes.
Good luck.
Alan

Suggest a long screwdriver to provide plenty of space between your ear and the warmish engine, heat exchangers, etc.

If there's a Harbor Freight nearby, buy their cheapish but usable mechanics stethoscope. Simple and handy to help isolate noises.

Sherwood

So, I finally ordered a mechanic's stethoscope, should arrive soon. I'll do a thorough job of listening everywhere you guys suggested.

In other news I sent my oil in for analysis just for grins, since I was changing it anyway. Here is the report if anyone is interested:

http://forums.pelicanparts.com/uploa...1413211350.jpg

Believe I have the same issue
 

I've bought a car just recently. The previous owner said something about a noise at the same side of the engine. Did you ever discover what the problem was?

The suspense is killing me. I gotta know what was the cause. I'm hoping it was loose exhaust!

This is an explanation but might not be the cause.
The Euro SC's 930-10's have forged pistons in nickies due to the higher CR. Forged pistons, in most every 'built' high CR V8 I've owned, have piston slap at idle that is the same kind of knock I hear in that vid. The cast US Alusils don't have this slap.
It goes away at higher rpm (not completely) but def gets quieter.
I have a 930-10 and it has a knock at idle, is freshly rebuilt by a pro...has fantastic leak down and goes like stink for the last 20k miles....also uses about 8-10 oz of oil in 3k miles.
I doubt you have an issue as this 'may' be your circumstance.

Mahle & KB pistons run very quietly, unlike JE and other 2618 pistons which need much more clearance.

Valid comparisons between Mahle & other 2618 forged pistons are impossible to make due to their totally dissimilar alloys and applications.

Steve,
My experience is pretty shallow but I've listened to 2 other euro 3.0's and they both had a bit of slap/knock in each one. As they warm it goes away but not totally and is only heard at idle.
Another shop owner told me it's pretty normal.
OTOH, what's in the video might be anything as trying to compare recorded sounds always escapes me.

USA/Euro 3.0's should not have any piston slap at all unless they have 2618 pistons (JE, CP, Woosner, etc) in them.

Mahle cast & forged pistons run very quietly unless something is wrong such as piston wear, pin bore wear, etc. New ones are dead quiet.

Okay Steve, you know a hellava lot more about this than I do.

Hi everyone! SmileWavy

No update other then that I got to run the car a couple hundred more miles before putting her up for the winter. I will have a good listen to the engine with the stethoscope when I get a free weekend, I just haven't had time and and weather has been lousy.


evan

Steve, since my P/Cs are of unknown vintage but are OEM 9:8:1 Euro spec, does that tell you anything about if they are Mahle or something else?

Without seeing your cylinders for myself, I cannot tell you precisely what you have, however if they are Euro 9.8:1 pistons, they are likely Mahle ones.

Nikasil and Ausil cylinders have very different appearances as well as markings at the base of the cylinder so if you can take some close-up, high-res pictures, I may be able to ID them for you.

Steve - hi, top or bottom of engine to id cylinders? Many thanks.

Evan,
Photos of the cylinders...as Steve says. What do you have?

Finally got time to snap a couple pics from underneath the car today... hereby delivered for the great Steve W. to evaluate. Any idea what I've got? I can take more pics if needed. TIA SmileWavy

http://forums.pelicanparts.com/uploa...1420909547.jpg

http://forums.pelicanparts.com/uploa...1420909583.jpg

Those look like Alusils to me, based on the pics.

Thanks Steve! I'll definitely have questions come rebuild time.

Now its just to wait for the snow to melt so I can get the car outside, run it and try out my mechanics stethoscope.

Out came the stethoscope for the first time today: back to trying to find the clackety noise. I'm not sure I know more then before but here is the lowdown:

• The noise is definitely on the right side of the motor (4-5-6)
• No clacking from the chain boxes
• Clacking audible on fan housing but very muted
• Audible on lower right rocker cover but muted
• Clearly audible on upper rocker cover but not loudest here either
• Clearly audible from underneath the heads
• Clearly audible from exhaust flanges but again not loudest
• LOUD from 4-5-6 intake runners next to each injector. On cylinder 4, I can FEEL the clack through the stethoscope wand :eek:
• Really LOUD with the wand on the right SSI header
• Barely audible from the underside of the case which leads me to believe its not bottom end

Again, this is a metallic thuck-thuck-thuck-thuck noise, apporximately four times a second at 7 - 800 RPM (idling slowly with oil cap removed, sound is most audible this way.) The clack speeds up according to engine RPM and gets harder to hear with the other noises over 3K but is still there.

You'll recall I've had the right side rocker covers off and checked valve clearances and these were in spec, no rocker shafts out of place, no oil or exhaust leaks. Sounds like a little engine gremlin is smaking something metal inside the engine with ball peen hammer four times a second, and I can't find the little bugger. :mad:

Next I'll put the car in the air and run it to better probe around underneath the motor. Thoughts welcome! SmileWavy

So, here are my thoughts/options. Valve guide loose (probably inlet), small end bush loose, or maybe they did not install the little wrist pin clips properly on #4.
This is just shooting from the hip, but if possible my next step might be to try and look inside #4. Don't know how do-able this is but others will have the knowledge if it is. I'm thinking of those small internal probe type lights/cameras. If it is possible, I would get #4 piston to the bottom and try and inspect the lining of the cyl, looking for marks.
On the upside - I had exactly the same issue (on #2) after rebuilding my engine from the crank up. I could feel it on the cylinder housing. After trying everything else, I reluctantly tore the engine down to the short block looking/measuring for any sign of something wrong. And found NOTHING. Had no option but to bolt it up again.from memory the noise was still there, but finally went away, and some years and about 20-30k later, it is perfect. Go figure.
Alan

Could the exhaust flange be leaking?? I found mine warped somehow and caused a leak. Same issue happened to a buddy doing a rebuild. Solution is to remove and file the flange flat. Reinstalled with new gaskets and I used a little high heat silicone. 100% OK now.

Certainly can make a sound like described - but unlikely to make the vibration he can feel in #4, IMHO.
Alan

Thanks Alan, I recall you describing your engine that fixed itself. I'm not counting on that happening, but you have some good suggestions as always. The heads were left untouched when the PO had the rebuild done other then machining of the mating surfaces... so valves/seats/springs/guides have 160K miles on them and possibly a lot of neglegt along the way. I couldn't find any broken springs when I had the covers off, so at some point I'm going to have to do a teardown. Problem is that means a full rebuild 'cause there is no way I'm dropping the motor to do things halfway.

My electrician buddy has some kind of probe camera I can borrow. Not sure if it will fit in a plug hole but its worth asking.

I can't find any leaks, and this is a metallic clack I can feel. Imagine someone was under the car tapping the engine with a hammer four times a second and thats about what I have.

Maybe a rocker of broken. Good luck. ;-)

I had both covers off on the right side and rockers/shafts are fine, valves are in adjustment. I couldn't find any broken springs but I suppose an inner spring could be gone that I couldn't see.

Really nice. Well done.
Cheers,
Resmas

Not easy to find the cause of this clac clac, it is maybe due to a bad regulation of the game(set,play) of valve too important for the admission 4.