Fiat Coupe Club UK

Engine Noise - Dead or not? Advice needed (vids)

Posted By: Anonymous

Engine Noise - Dead or not? Advice needed (vids) - 02/11/2010 22:34

further to my post Here

Marco came round tonight to have a look at the failure.

I'll let him explain all the things he checked.

Suspect bottom end gone..... but only by ruling out other issues.
The two things that make us (well Marco as I have no idea) is that the sound is very "top" of engine, almost towards back of engine.
Also if the bottom end had gone, it should have low oil pressure. Mine is still holding 2.75 - 3 bar (See Video).

So this is for all those times where you've heard a funky noise, hopefully someone has heared this before and can shed some light on the problem.

Videos
Outside the car

Inside showing oil pressure
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 02/11/2010 22:51

by the way, i'm sat in the corner, faced towards the wall, head in hands waiting for reality to hit me.

on the bright side, its an excuse to buy a new one smile

poto blue or maybe moon grey anyone??
Posted By: Theresa

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 02:24

It does sound like the bottom end, especially when you rev it from inside the car frown
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 09:37

sounds nearly the same as mine did when my bottom end went, does not sound good mate
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 10:04

it really weird..

we checked every thing on the car.
it sounds horrible.

i am 90% sure its the bottom end Karl... sorry mate.

we checked the cam belt, cam shaft's, lifters, plugs, injectors every thing really..

the big kick in the face was the little bits of metal in the oil..

sorry Karl.. frown
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 10:08

metal in oil = suicide sorry mate
Posted By: samsite999

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 10:16

Sounds like bottom end, if marco found bits of metal in there its game over frown
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 10:52

Bottom end 99.9%
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 11:00

so question is what to do with it?
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 11:50

break it..
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 12:22

i've not got the room mate, or tools or time


see thread here

If another coupe turns up, i will be keeping her to transfer all the mods over.
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 12:47

ask marco what to do iv text him an idea for you
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 13:29

got the text, nice one Nase!

i will speak to Karl...

brilliant!
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 17:21

I have no experience with this, but if you capture the audio
from the outside clip its 10Hz frequency i.e. corresponding
to 600rpm - thats low idle?
or is it because noise is from one of the cams that runs at half the speed of crank/engine rpm?
just a thought...
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 03/11/2010 22:41

Originally Posted By: mli
I have no experience with this, but if you capture the audio
from the outside clip its 10Hz frequency i.e. corresponding
to 600rpm - thats low idle?
or is it because noise is from one of the cams that runs at half the speed of crank/engine rpm?
just a thought...



shocked confused shocked
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 04/11/2010 13:15

in otherwords its still broken
Posted By: Barmybob

Re: Engine Noise - Dead or not? Advice needed (vids) - 04/11/2010 14:45

That sounds more like top end to me, not good though frown
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 04/11/2010 15:55

I have no idea what MLI is on about lol.

it does sound "VERY" top end. But after checking it over, there are just no signs of top end fault frown

I may break this car, but keep the tuning mods.
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 05/11/2010 07:30

sorry karl smile
A bit more explanation:
I think the 'clacking' sounded 'slower' than normal engine idle speed.
So i analysed the sound in an audio editor tool.
Here I could count the 'clacking' noise to ~10 pr sec (10Hz).
This would correspond to ~600 RPM /IF/ its coming from the crank (=engine speed).
My point is that it might be more likely that the
'clacking' comes from one of the cam-shafts which is
turning at half the engine/crank speed?
i.e. noise at 600 'clacks pr min' while engine is
running at 1200 RPM
(maybe you had engine speed at 1200rpm in the 'outside' clip?)

easier to understand now?
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 05/11/2010 12:14

yes.

car was at normal idle in vid.
Posted By: MCMike

Re: Engine Noise - Dead or not? Advice needed (vids) - 07/11/2010 21:49

Sounds like bottom end to me to frown
Posted By: stinky

Re: Engine Noise - Dead or not? Advice needed (vids) - 07/11/2010 23:28

probably bottom end but when the barchetta variators go they sound just like that,so slim chance it could be variator related
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 27/02/2018 23:04

Hi All

I'm reviving this old thread...

My own 20vt has knocking noise:

20vt knocking noise

Note:
Cold engine: not present
warm engine: present at idle - not present above 1500rpm.
Oil pressure when hot is 2,5bar at idle and 3bar at 1500+rpm

history:
Some years back I changed the cylinder head (blown gasket).
Since then the car has been standing still (occasionally started a few times).
I was suspecting top end - i.e. stuck tappets (used a bad one in the head change? - back then I think it also had knocking noise after head change).

Last week I took off the camshaft/rocker cover and removed the camshafts.
Then I took out all 20 tappets and dismantled and cleaned each of them.
Everything back in place and started the engine.
At first a lot of ticking but no knocking - when the engine got hot the ticking more or less dissapeared (normal) - but knocking came back :-(
I had the engine running at 2000rpm for a while to fill and adjust tappets.

After reading Karl's post again and viewing some vid's - I'm now also supecting a bad crank bearing ? (bottom end) shocked oh my...

Could maybe also be bad timing?
- I have the cam-locks so need to check next time I'm at the workshop...

Note: i did perform audio analysis - the knocking is appearing with a frequency corresponding to ~350rpm - so same speed as crankshaft (or every second stroke of a cylinder I guess...).

Any hints?

Thanks,
M
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 27/02/2018 23:56

Sounds more like top end to me. Strange that it goes away at high revs, maybe a blocked oilway that needs the higher pressure of high revs to pass oil?
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 01/03/2018 20:24

Thanks karl
I'll check oilpipes - what i can see.

Then also disconnect 1 sparkplug at the time to check what happens...
(But not for 10 days - going skiing...)

M
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 05/03/2018 21:11

Just drop the sump and and check big ends guessing over
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 24/03/2018 16:07

Hi guys

Update:
I can't really see anything on oil pipes but haven't dismantled them.

As mentioned I have disassembled all 20 hydraulic tappets, cleaned them and assembled all in (still noise).
Last weekend I took off rocker when engine was cold and then when it was hot. On each occasion I checkedk each tappet for movement.
I found 4 that was spongy as if not filled. Hence they could be reason for noise.
So, off with camshaft and replaced 4 tappets. Reassembled and did valve timing (getting good training at this smile )

But there's still noise :-(

So today I warmed up engine and removed rocker cover. I checked all tappets again - this time no-one is spongy - good.

Noise appears like this:
Cold engine, idle: clacking/knocking noise
After some 5mins, idle: noise gone and engine sounds nice!
After reaching working temp, idle: clacking/knocking noise (a bit better/softer sound than cold)
Warm, above 1100rpm: no noise

I don't think it's bottom end as it's clearly higher sound when i listen above engine (vs below).

This about difference when cold/warm and high/low revs could also point at oil viscosity?
I had used 10w-60 castrol sport oil. Maybe not good as 10w-40 recommended. Maybe too thin when hot?
I'm going to try std 10w-40...

M
Posted By: Countrycruising

Re: Engine Noise - Dead or not? Advice needed (vids) - 25/03/2018 05:49

So possible lazy or seized valves on the hydraulic lifters, either way it is sounding positive, and with the oil you're using the same weight with the 10 grade oil, the 40 and 60 are the optimum working temps so my personal choice would be 60 as induction temps rocket with spirited drivings so the 60 will hold a better viscosity.
Posted By: magooagain

Re: Engine Noise - Dead or not? Advice needed (vids) - 25/03/2018 09:15

If you were not talking about the valve lifters ,from you're description it sounds like cracked manifold .
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 25/03/2018 11:08

Once it's running OK and noise is gone how long does it take at idle until the noise returns? A few seconds or a few minutes?

If it's only happening after minutes of idling I'd just drive the car normally and forget about it. If it doesn't happen under normal driving conditions then it's probably just a slightly restricted oilway (inside the head or tappet) causing a tappet to not automatically refill due to the lower oil pressure at idle.

Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 25/03/2018 21:54

Thanks for following up guys.

@ cc: yeah 10w-60 probably best - I think I misunderstood SAE J300 when I read about it yesterday. 60 means higher viscosity at hot engine... When I changed to 10w-40 last night my oilpressure dropped to 1.5bar hot idle (from 2.5bar with 10w-60).
Also noise is slightly worse with 10w-40 - and comes back a bit quicker when going from 1500rpm back to idle. (Oilpressure drops slightly quicker as well).

@mago: i guess noise from manifold would not disappear when changing temp/revs?

@graham: I haven't timed exactly - but my notion is that noise is there for 2-3mins after cold start. Then while engine is warming up the noise disappear for about 7-10mins.
Then the noise start to appear slowly when engine reaches normal temp.

My theory was that some tappets were not able to keep oilpressure inside (eg due to poor retain valve inside) - hence I cleaned all and changed 4.
But since all feels hard now I'm not sure...
I'm considering now if it's due to 1 or more tappets being too small in diameter - hence can tilt slightly when pushed by cam? I noticed that one tappet can tilt slightly...
Can this create noise when hitting cylinder for tappets?
I guess noise from this would disappear with higher oilpressure.

Re lazy valve: not sure I understand how noise can disappear if this is the reason.

@graham re blocked oil channel: this is a used cylinder head I got - don't know if it's been stored for long all dirty.
Now I'm sad I didn't do a complete cleaning of it before installing...

Next step:
Check gaps for tappets with gauge.
Recheck hardness and tilt for all tappets.
Posted By: Nigel

Re: Engine Noise - Dead or not? Advice needed (vids) - 26/03/2018 04:25

Has this engine been run at high boost? (Eg 1.5 bar or above?)

Is it modified at all?

I only ask because I had all 20 tappets replaced on my last Coupe and it turned out to be a bent rod (piston slapped the bore on the exhaust stroke only, hence a “half engine speed” knocking)
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 26/03/2018 08:16

Once it's warmed up and the knocking is there at idle, then you rev it and noise disappears... how long does it take for noise to come back when you stop revving it and engine is idling again?

Have you actually driven it properly on the road to see what happens when you have high oil pressure for a long time?
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 26/03/2018 20:38

Thanks for interest and inputs!

@nigel
I don't have complete history but I haven't pushed it very hard.
But the reason for changing the cylinder head was blown gasket and water coming in one (or two) of the cylinders.
This could have lead to bent piston rod I guess :-/ (oh my)
As I recall - but not sure at all - pistons were flush with engine block. Maybe thats what I want to remember...

In your case did the knocking disappear when revs were a bit higher? (Eg >1500rpm)


@graham: the noise/clacking/knocking reappear some 2-3secs after drops to idle. Following the drop in oilpressure it seems.
I haven't had the car on the road recently. No registration... But a few trips around the field could probably be done without risk :-) (countryside)
As replacement for driving I had it running at 3000rpm for 1-2mins - after warming up - after changing tappets.

M
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 26/03/2018 20:45

Sorry nigel: I think it's standard turbo etc - the guy that had it before me wanted to keep an original setup.
(It has adjustable shocks though...)
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 26/03/2018 21:00

Go give it the Italian road test lol
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 27/03/2018 06:05

Yep moon smile Will do Thursday.

If it's actually oil channels that are a bit restricted by sludge then maybe I should try putting a cleaning agent in the oil?
I watched some videos of people (us guys) trying cleaning agent in oil when having noisy valves/tappets. It worked for some of them.
Does anyone have experience with this? (Some states there's a risk of overfilled filter hence sending debris around filter through by-pass)

M
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 27/03/2018 19:33

Hi guys

Further updates:

Tried oil system cleaning: warm idle oilpressure went up to 1.9-2.0bar - nice. (From 1.5bar before)
Did not change clacking/knocking noise though...

But I timed when noise starts (at idle):
At cold start: various noise incl clacking
After 3mins: begins going silent
After 10mins: clacking slowly begins.

Another finding:
Warm engine- noise is there: when I pull out cyl3 ignition coil then noise is muted significantly (although still there)

Listen/watch here:
Cold start with various noise:
coldstartnoise
After 3-4mins getting quiet:
after8mins
When warm - notice when cylinder 3 disconnect:
noise warm

So, I tend to think that I have 'piston slap' ? eg due to a bent rod :-( so this only give noise on exhaust stroke... (Hence at half engine speed)
@graham: like yours?

I'm not really happy though :-(
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 27/03/2018 19:40

Hi guys

Further updates:

Tried oil system cleaning: warm idle oilpressure went up to 1.9-2.0bar - nice. (From 1.5bar)
Did not change clacking/knocking noise though...

But I timed when noise starts (at idle):
At cold start: various noise incl clacking
After 3mins: begins going silent
After 10mins: clacking slowly begins.

Another finding:
Warm engine- noise is there: when I pull out cyl3 ignition coil then noise is muted significantly (although still there)

Listen/watch here:
Cold start with various noise:
coldstartnoise
After 3-4mins getting quiet:
after8mins
When warm - notice when cylinder 3 disconnect:
noise warm

So, I tend to think that I have 'piston slap' ? eg due to a bent rod :-( so this only give noise on exhaust stroke... (Hence at half engine speed)
@nigel: like yours?

I'm not really happy though :-(
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 27/03/2018 20:04

Mine sounds like this and it's just a noisy tappet:

http://sendvid.com/mbumb1uc

If mine is left idling for a long time the tappet gets noisy like that but after a few mins of normal driving it's OK again. Fine from cold start too unless it's been left standing for weeks, but most coupes have noisy tappets then.

If your noise is going away with high revs but appearing again within a few secs of idling then it may not just be a tappet, as a tappet shouldn't be draining that quickly unless it has a major problem.
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 28/03/2018 21:45

Try to measure the compression of each cylinder.

You should get something about 150 psi or 10 bar.

Differences between cylinders greater than 20% is not good.

This test will tell you if your engine have a bad gaskets and/or bent rod/pin.

Here is a how to, just in case
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 02/05/2018 17:03

Hi Guys.

Sorry for the silence - I had to fix some stuff in the garden/house...

@graham: you're right - with functional tappets they should stay 'full' after first running in. And when I checked last time they were all firm (rocker cover off and pushed each with a plastic pin).

@ SVC: My plan was to check compression on all cylinders this week - but ran short of time frown

Other news:
I gave it a good italian road test Monday :-)
I seem to have power.
But I noticed a couple of times: when accelerating modestly I seem to hear clacking/knocking noise following revs - indicating trouble...

So, a couple of theories:

1. bent rod on cylinder 3
-> seems valid as I can hear reduction of noise when removing coil on #3
-> need to confirm with compression test

2. lazy valve (i.e. having trouble returning completely to seat)
-> no experience with this - but cant understand how the cold start scenario fits with this (noise - silent - then noise; see above)
-> this would require head off to check I guess :-/

3. loose/spongy tappets
-> I don't believe in this theory anymore.

BTW:
Went for Danish MOT today - my CO was now ok (failed last time - I believe its because I replaced injector on cylinder 1).
However the car failed on airbag lamp on :-(
(not allowed in DK apparently)

Cheers,
M
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 07/09/2019 14:47

Hi All

Continuing an old story...

Im trying to get ready to disassemble the engine...
But maybe someone could give last advice?

Short recap: first i had engine full stop after overheating (bad temp switch?) - which gave blown head gasket (head bent).
Head replaced (used) and new gasket.
Running ok w good power but the issue is a clacking noise at half engine rpm. Not present when warm above 1500rpm.
Noise gets vague if cyl 3 ign coil disconnected.
Seems to come mostly from topend center (around #3).
All 20 tappets disassembled cleaned and oiled. All hard.
Oil pressure 1.9-2.0bar hot idle acc to dash gauge.

Compression test:
#1: 11.5/11.6
#2: 11.4/11.6
#3: 11.2/11.5
#4: 11.0/11.3
#5: 11.5/11.9
Pretty decent and low variance?

Should I go for new crank bearings?
Or piston slap? (Which means all out I guess?)

Cheers
M
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 23/01/2020 23:17

Hi all

My contribution here havent been the best - sorry.
I hope you might still want to join thread anyway.
Old story of my sprint that has been standing still a lot due to this issue (luckily inside my moms big garage).

Short recap:
first I had engine halt after overheating (bad temp switch?) - which gave a blown head gasket (& head slightly bent).
Head was replaced (used) with new head gasket.

Issue:
Running ok w good power but the issue is a (metallic) clacking noise (Audio files above).

Observations:
Frequency of noise is corresponding to half engine RPM (determined from PC audio analysis).
Clacking is not present when warm and running above 1500rpm - Reappearing 2-3sec after returning to idle.
Audible but vauge when accelerating modestly.
Noise gets vague if cyl 3 ignition coil is disconnected.
Seems to come mostly from center (around cyl #3) at top end - but can be heard from below.
Oil pressure 1.9-2.0bar hot idle acc to dash gauge - 3bar at 1500rpm+.

...
Actions done:
Oil system cleaning - rechanging oil a couple of times afterwards (and filter).
All 20 valve tappets were disassembled, cleaned and oiled - all are hard now.
Compression test showed its fairly equal on all cyls (within ~5% variation).

Latest:
I removed the sump (d*** what a bitch - not least because of A/C piping :-/ )
And then removed rod caps & bearings - carefully noting position and orientation.
BTW: (plastic) bushing for oil dipstick was damaged - seems hard to get a new one...

...
Theories:

a) Bent rod (cyl#3) -> piston slap
. I guess there would be bad compression on the relevant cyl?

b) loose pin (cyl#3) -> piston slap
. I can NOT feel any vertical play when pushing/pulling (any) rod from below...
. but I can tilt the piston(s) sideways ('quite a bit') perpendicular to pin axis...
(they move nicely along pin axis as they should)
. I can see a bit of scoring in cyl#3:
click to enlarge
. but I would have expected this was a 'broader area' at lowest end of cyl?

c) Exhaust leak - eg from poorly assembled ex-manifold?
. I guess this wont change with temp? (nor dissappear with higher rpm?)

d) Bad (con) rod bearings?
. I dont think they look totally bad:
click to enlarge
although there are signs of dirt in oil + one withoil starvation? + one with strange 'middle wear'.
. Maybe one of them (eg cyl#3) could be smashed from water in chamber?
but I forgot to check vertical play of pistons before removing all rod bearings :-/

e) Bad main (crank) bearings
. ? - I have not taken these off yet...

f) Loose valvepin (cyl#3)? (lazy?) -> knocked by tappets (cam)
. maybe - I did not disassemble the head before mounting :-/
. but I guess this would NOT change with RPM/oil pressure?

g) Bad sparkplug (cyl#3) - giving unwanted detonation
. I guess this would NOT change with RPM/oil pressure?
. I do have carbon build up in cyl#3 - quite a bit compared to when head was changed
click to enlarge
click to enlarge

h) bad injector? giving unwanted detonation
. this would also affect power, idle etc?
. I guess this would NOT change with RPM/oil pressure?

i) a tappet that can tilt slightly in 'housing'-> clacking on sidewall when hit by cam
. I could try to exhange tappets btw cylinders...

Comments / suggestions welcome:-)
Thx M
Posted By: Grigio

Re: Engine Noise - Dead or not? Advice needed (vids) - 24/01/2020 07:15

Originally Posted by mli
b) loose pin (cyl#3) -> piston slap
. I can NOT feel any vertical play when pushing/pulling (any) rod from below...
. but I can tilt the piston(s) sideways ('quite a bit') perpendicular to pin axis...
(they move nicely along pin axis as they should)
. I can see a bit of scoring in cyl#3:
click to enlarge
. but I would have expected this was a 'broader area' at lowest end of cyl?


There is obvious heat colouring on the piston that corresponds with the scoring of the bore. That piston should come out to determine the cause. Broken ring is my call.
Posted By: Countrycruising

Re: Engine Noise - Dead or not? Advice needed (vids) - 24/01/2020 09:24

It could be detonation due to a failing injector, if it overheats the ring it'll drag down the cylinder as shown in your underside picture.
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 24/01/2020 22:55

Thanks Guys

@grigio: yes - I noticed that as well frown I hope its not too much to save the cylinder-wall...
How would you explain the change of noise acc to engine temp?
- cold start:some clacking - after 4mins: almost silent - hot idle: more clacking...
I had a feeling that the silent phase was due to 'full oil supply at medium viscosity'
- then when oil gets warmer/thinner it changes.
Is this a matter of thermal expansion of cylinder vs (broken) ring?
Or maybe a combination with something else?

@CC: I should have tried to switch both sparkplugs and injectors btw cylinders before disassembly :-/
Would detonationchange with temp? (prominent->almost->more prominent)

..
Any comments to the condition of the rod bearings?
It seems theres dirt - maybe from poor assembly of head :-/ This would call for proper re-build...

BTW: Mileage: ~182000km

Cheers
M
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 10/02/2020 22:37

Hi guys

Update:
Now I have exchanged both rod-bearings and main bearings in situ (after checking old gap with plastigauge).
(top main bearing shell #1 and #6 were hard to get out just put pushing with fingers/plastic-bit
- I guess they're loaded by flywheel and stuff. So I used a cut-down 'head' of a cable-tie and pushed it into the
oilhole on the crank and then turned the crank; and voila it pushes out the top shell...)

Note: Main bearing #1 is looking like rod-bearing on cyl1 - signs of dirt and a bit extra wear.
But they're not totally bad...

Anyway: after assembly and starting up the engine: the knocking/tapping sound is still there :-(
So theory d & e can be removed from the list.
Theory g & h can be checked now when engine is running (swap btw cylinders)
Theory a + b still to be checked... (engine disassembly)

When checking sound carefully now, it also feels like its mostly coming from 'middle of the engine' - higher sounds here than below engine...
And it is quite harsh 'metallic' sound.

Re. theory i) tappet tilt: I dont think I can feel any sideways play on tappets (with cams in place) - need to check w/o cams I guess.
(vetical play is non-existant - I can not get a 0,05mm 'blade' in btw tappet and cam-lobes...)

New theory j): (partially) blocked oilway for tappet(s) - but today it was almost totally silent after 3-4mins running - so not likely.

New theory k): one of the tappets is too small in Ø ? i.e. it cant be filled properly when oil is hot because oil leaks around it.
When oil is cold this gives enough resistance to fill tappet?
This support the symptoms: sound prominent at cold start -> almost silent after a few mins -> sound prominent when oil//engine hot.

(Or is one of the tappets still bad - even after disassy and cleaning? :-/ )

BTW: this whole sump removal and refitting feels more painful/cumbersome that timing-belt change IMHO :-(
I had to cut/disassemble the power-steering lines and 'bend' them out of the way
- and I removed exhaust from turbo as well (i.e. lambda sensor off).

Cheers
M
Posted By: Countrycruising

Re: Engine Noise - Dead or not? Advice needed (vids) - 11/02/2020 08:56

So a quick recap, you've stripped this engine, head off and pistons out for a full inspection of the rods, ring valleys etc, rebuilt and still makes that knocking noise when hot as posted in the sound wave 23/03/18?

What was found and resolved for the scuffing on the cylinder bore. piston etc?
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 11/02/2020 22:24

Thanks CC

No sorry :-/ since the images from underneath 23.jan-2020 (sump off) I only replaced bearings - Im not moving that fast... :-/
In 2010: blown gasket - full stop.
The (used) head replacement was in 2011 - after this the (clacking/knocking) noise came immediately
(and the car was sitting there for some years \ no money&time).
In march 2018 I disasssembled, cleaned and reinstalled all tappets - same noise. Pause in 2019...
Here in Jan'20 I decided to open sump and look at bearings (since I didnt find issues with tappets) - and then realised the scuffing on Cyl3 seen above.
After main/rod bearing replacement still same noise.

I will need to take the engine apart to deal with scuffing... However I would like to (try to) ensure that the cause of the noise is not somewhere else before I do that.

Cheers
M
Posted By: Anonymous

Re: Engine Noise - Dead or not? Advice needed (vids) - 11/02/2020 23:00

I still think it might be a partially blocked oilway in the head. Have you tried an aggressive oil flush like BG EPR ?
Posted By: Countrycruising

Re: Engine Noise - Dead or not? Advice needed (vids) - 12/02/2020 10:19

To be honest I think you're that far in to this the only way to truly ascertain what's going on is completely strip the engine and inspect everything meticulously,you could spend another year chasing your tail without any answers, and the scored bore is already an issue that needs dealing with so a weekends work and I bet the problem will become apparent.
Posted By: mli

Re: Engine Noise - Dead or not? Advice needed (vids) - 12/02/2020 21:34

@ graham: I think the 'OSC' I used was probably a more 'normal' one... I dont know about BG EPR - seems it could be a good option. I was actually going to try to 'blow air' into oilways supplying suspected cylinders/tappets...
I hope the stuff BG EPR 'releases' goes in my oilfilter and not into the new bearings...

@CC: yes you're right - I already spent too much time on error hunting. and cyl 3 piston/rings needs to be inspected. As said 'strip' is my main next step...

Thanks for support.

Cheers
M
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