Welcome to 911UK
The only place for Porsche, 911uk is the definitive enthusiast and resource site for the Porsche 911.
Registration is fast, simple and absolutely free, so join up today for full access to the site and benefit from latest member offers.

Porsche Classifieds
Sell Your Porsche on 911uk
Create a Free Classified Advert
Search Ads
Classified Adverts FAQ
Trade Classified Information
Buyer & Seller Fraud Protection
Consumer Rights Act
Pre Purchase Inspection (PPI)
Porsche Car Sourcing
Porsche Cars Wanted
Official Porsche Centre Reviews
Model
Stock
Porsche 911
992 : 2019- 0
991 : 2011- 22
997 : 2004- 60
996 : 1997-2005 29
993 : 1993-1998 3
964 : 1989-1993 0
Carrera 3.2 : 1983-1989 2
Carrera SC : 1977-1983 1
930 Turbo : 1975-1989 1
Early 911 : 1964-1977 1
Porsche Other Models
Classic : 1950-1965 0
Boxster : 1997- 26
Cayman : 2005- 19
Cayenne : 2003- 5
Macan : 2014- 4
Panamera : 2009- 0
912-914-924-928-944-968 0
959 - CarreraGT - RaceCar 0
Car Parts For Sale & Wanted
Other Items For Sale & Wanted
Wheels Tyres For Sale & Wanted
Number Plates For Sale Wanted

Porsche Services
Porsche Body Shop Repair
Paint Protection & Wrapping
Porsche Classic Insurance
Porsche Classic Parts
Porsche Classic Restoration
Porsche Design Collection
Porsche Engine Gearbox Rebuild
Porsche Heritage & History
Porsche News
Porsche Picture Gallery
Win a New Porsche 911

Porsche Parts
Body Parts, Body Styling
Brakes, Clearance
Electrical, Exhausts
Engine Cooling, Engine Electrical
Engine Rebuild, Heating Cooling
Interior Incar, Lighting
Rubber Seals, Service Parts
Steering, Suspension
Transmission, Workshop Tools
Early 911, 911 - 930, 928 - 968
964 - 993, 996 - 997, Boxster
Cayman, Cayenne, Panamera

Porsche Model Range
911 [992] 2018-Current
Porsche 911 [992]
911 [991] 2011-2019
Porsche 911 [991]
911 [997] 2004-2012
Porsche 911 [997]
911 [GT] GT1-GT2-GT3
Porsche 911 [GT]
911 [996] 1997-2005
Porsche 911 [996]
911 [993] 1993-1998
Porsche 911 [993]
911 [RS] RS-RSR
Porsche 911 [RS]
911 [964] 1989-1993
Porsche 911 [964]
911 3.2 1983-1989
Porsche 911 3.2 Carrera
911 SC 1977-1983
Porsche 911 SC
911 [Early] 1964-1977
Porsche 911 [Early]
Boxster & Cayman
Porsche Boxster & Cayman
Cayenne & Panamera
Porsche Cayenne & Panamera

911uk Site Partners

Post new topic   Reply to topic
Author Message
monster
Imola


Joined: 04 Sep 2010
Posts: 793
Location: Bournemouth


PostPosted: Sat Aug 17, 2019 8:16 pm    Post subject: Reply with quote

me&my997 wrote:
monster wrote:
A blowing exhaust can sometimes make a similar sound....


Have you listened to the clips Surprised


Yes, both clips. That is what led me to make the comment I made.

When trying to pinpoint a problem its best to consider all possibilities and I have heard similar noises in the past which initially sounded like a tapping sound but on further investigation turned out to be a blowing exhaust.
 
  
View user's profile Send private message
   
Robert SausageTrousers
Monza


Joined: 02 Apr 2018
Posts: 243



PostPosted: Sat Aug 17, 2019 9:53 pm    Post subject: Reply with quote

I had a good listen around mine this afternoon and it certainly doesn't sound like the video clip, i'd take it in somewhere for a looksee if I were you!
 
  
View user's profile Send private message
   
chowgar
Monza


Joined: 09 Aug 2014
Posts: 245
Location: London


PostPosted: Sun Aug 18, 2019 8:38 am    Post subject: Reply with quote

deMort wrote:
I answered via email my thoughts on this .. to be fair ill post it here ..



I've just uploaded the videos and posted them on the forum for others to
comment on ..

For me .. that's not a tappet sticking .. it does sound more chain related
, a little louder than i would have liked .

It seems to be more bank 2 so the o/s/r of the car .. it would be worth just
making sure all the plugs are tight on that bank as was mentioned on your
post .

I do know that rebuilt engines can have a chain type noise and there isn't
anything you can really do about it .

As with all videos of noises it may well be louder or quieter in real life
than the recordings shows , as such i would like , when ever you get the
chance just to get an Indy to have a listen and confirm its not a problem .

lets put it this way .. i have in the past told one guy not to start his car
again and to get it recovered on the forum .. with you its a noise I'm not
worried about as such but would like someone to listen to the car instead of
remotely like i am.

Basically it needs to go on a ramp and confirm the noise is from the
tensioner area that side .



i've not had a reply so can't comment further and my " help " wasn't that good .. . i don't have an answer basically .


Maybe this is why the OPC replaced my timing chain when they rebuilt my engine. The master tech said, that they usually do this as a matter of course due to often finding blackness in the chain. I believe they also replaced the chain tensioners.
 
  
View user's profile Send private message
   
SJD
Trainee


Joined: 02 Apr 2014
Posts: 54
Location: Perthshire


PostPosted: Sun Aug 18, 2019 10:44 am    Post subject: Reply with quote

deMort wrote:
I answered via email my thoughts on this .. to be fair ill post it here ..



I've just uploaded the videos and posted them on the forum for others to
comment on ..

For me .. that's not a tappet sticking .. it does sound more chain related
, a little louder than i would have liked .

It seems to be more bank 2 so the o/s/r of the car .. it would be worth just
making sure all the plugs are tight on that bank as was mentioned on your
post .

I do know that rebuilt engines can have a chain type noise and there isn't
anything you can really do about it .

As with all videos of noises it may well be louder or quieter in real life
than the recordings shows , as such i would like , when ever you get the
chance just to get an Indy to have a listen and confirm its not a problem .

lets put it this way .. i have in the past told one guy not to start his car
again and to get it recovered on the forum .. with you its a noise I'm not
worried about as such but would like someone to listen to the car instead of
remotely like i am.

Basically it needs to go on a ramp and confirm the noise is from the
tensioner area that side .



i've not had a reply so can't comment further and my " help " wasn't that good .. . i don't have an answer basically .


Apologies for the delay in my response.

Thanks for the support and feedback, really appreciated.

I’ll get the car booked into the Indy I use and may also consider gaining the opinion of my local OPC.

My Indy had previously mentioned the chain tensioners but no immediate concern.

The noise is annoying and something I’ve lived with too long without really getting to the source. I had read Hartech comments previously and thanks to Baz for commenting again but I still hope it’s something that can be sorted.

With the contributions from all on this great forum it will help me decide the next steps I take. Could be a good few weeks before I get the car looked at.

Thanks again!!
 
  
View user's profile Send private message
   
DAVIDGT996
Trainee


Joined: 24 Feb 2019
Posts: 77
Location: Colchester


PostPosted: Sun Aug 18, 2019 10:59 am    Post subject: Reply with quote

My 996 has developed the exact same noise as yours on the same side - offside rear.

Noticed it a few weeks back when on idle and on low revs. Seems to disappear at higher revs or just not noticeable as much.

Mine is booked with my local Indy next week for plug change and investigation.
_________________
2001 C2 Coupe Tip
Black, GT3 kit, lowered
 
  
View user's profile Send private message
   
bazhart
Approved Trader


Joined: 20 May 2009
Posts: 1004
Location: Bolton Lancashire


PostPosted: Sun Aug 18, 2019 1:43 pm    Post subject: Reply with quote

Probably the most difficult to analyse from a recording and you really need to take the car somewhere they are more familiar with the noises and their consequences.

The fact that the noise rises with revs is odd if it is related to a tensioner because the oil pressure soon rises with revs and usually provides enough pressure to dampen out and chain snatch - unless there is something else out of balance between cylinder firings that causes a drop in revs every time that cylinder fires and a consequent snatch when the tickover is automatically raised to compensate.

Anything that unbalances the tickover on one cylinder can be a cause and this includes exhaust manifold connections, loose plug, burnt or bent valve, sticky or weak tappet, sticky fuel injector or a fuel injector out of delivery scale on tickover, inlet manifold leak, exhaust leaks, ignition coil damage, loose valve seat, bent or burnt or coked up valve and some sound metallic even though they are the result of exhaust leaks or plug leaks (list not exhaustive by any means).

A big end on its way out sounds similar and noises rise with revs - but you should be able to see evidence of that in the oil filter.

A damaged piston can also make similar noises but if the engine had 6 Nikasil liners that is highly unlikely unless something fell into a cylinder.

We would be happy to listen to it if you want to bring it up to us by appointment.

It may also be just one of those that some engines have as a result of general wear. This is because the tickover control is set from new as low as possible to just avoid a ticking noise - but as parts wear a bit (like hydraulic tensioners and really all the parts I have listed above) it sometimes unbalances the tickover which needs to be higher.

Sometimes a rebuilt engine with Nikasil cylinders runs with slightly better compression at low revs and results in the tickover control hunting a bit and as it does so the tick can come and go but as I mentioned above it usually goes away as revs rise when there is more oil pressure to the tensioners.

I agree it can be very irritating but having spent hours and a lot of money changing just about everything you could ever think of on some of our own engines without either sourcing the cause or eliminating it - you may have to try and ignore it.

Just one final point - has the car had an oil change and is it presently running with a lower viscosity oil (as per original handbook recommendations)?

Baz
_________________
Click here for the Hartech

You can trust us to "CARE FOR YOUR PORSCHE"
www.hartech.org
 
  
View user's profile Send private message Send e-mail Visit poster's website
   
DAVIDGT996
Trainee


Joined: 24 Feb 2019
Posts: 77
Location: Colchester


PostPosted: Sun Aug 18, 2019 3:19 pm    Post subject: Reply with quote

bazhart wrote:


Just one final point - has the car had an oil change and is it presently running with a lower viscosity oil (as per original handbook recommendations)?

Baz
[img][/img][img]mine funnily enough started after i did an oil change. I put the recommended oil grade in 5w40 total quartz 9000. Just wondered if the previous owner was running on a different grade oil.[/img]
_________________
2001 C2 Coupe Tip
Black, GT3 kit, lowered
 
  
View user's profile Send private message
   
bazhart
Approved Trader


Joined: 20 May 2009
Posts: 1004
Location: Bolton Lancashire


PostPosted: Sun Aug 18, 2019 5:54 pm    Post subject: Reply with quote

We recommend 10W50 Nanodrive be interesting to try it but it’s takes a while to purge the thinner oil from some of the tensioner.

Baz
_________________
Click here for the Hartech

You can trust us to "CARE FOR YOUR PORSCHE"
www.hartech.org
 
  
View user's profile Send private message Send e-mail Visit poster's website
   
SJD
Trainee


Joined: 02 Apr 2014
Posts: 54
Location: Perthshire


PostPosted: Tue Aug 20, 2019 4:58 pm    Post subject: Reply with quote

bazhart wrote:
We recommend 10W50 Nanodrive be interesting to try it but it’s takes a while to purge the thinner oil from some of the tensioner.

Baz


I’ve been running Millers Nanodrive since the rebuild, best part of 5 years ago now. Gets an oil change every year and is due for a service. It’ll get another dose of 10W50.
 
  
View user's profile Send private message
   
bullet-proof_biscuit
Newbie


Joined: 10 Jun 2019
Posts: 45



PostPosted: Tue Aug 27, 2019 1:35 pm    Post subject: same! Reply with quote

My 997.1 3.8S melty edition does exactly this, bore scoped and no score, interesting it can be loose plug, exhaust leak, tandem pump etc, at leas they are easy, if a little labour intensive wins.

Given me something to take apart on the weekend now!

Beers!
 
  
View user's profile Send private message
   
DAVIDGT996
Trainee


Joined: 24 Feb 2019
Posts: 77
Location: Colchester


PostPosted: Wed Sep 25, 2019 2:48 pm    Post subject: Reply with quote

[quote="SJD"]
deMort wrote:
Thanks for the support and feedback, really appreciated.

I’ll get the car booked into the Indy I use and may also consider gaining the opinion of my local OPC.

My Indy had previously mentioned the chain tensioners but no immediate concern.

The noise is annoying and something I’ve lived with too long without really getting to the source. I had read Hartech comments previously and thanks to Baz for commenting again but I still hope it’s something that can be sorted.

With the contributions from all on this great forum it will help me decide the next steps I take. Could be a good few weeks before I get the car looked at.

Thanks again!!
Did you get your ticking noise looked into as mine turned out to be big end bearing failure.
_________________
2001 C2 Coupe Tip
Black, GT3 kit, lowered
 
  
View user's profile Send private message
   
alpinaman
Montreal


Joined: 21 Feb 2012
Posts: 589



PostPosted: Wed Sep 25, 2019 5:58 pm    Post subject: Reply with quote

[quote="DAVIDGT996"]
SJD wrote:
deMort wrote:
Thanks for the support and feedback, really appreciated.

I’ll get the car booked into the Indy I use and may also consider gaining the opinion of my local OPC.

My Indy had previously mentioned the chain tensioners but no immediate concern.

The noise is annoying and something I’ve lived with too long without really getting to the source. I had read Hartech comments previously and thanks to Baz for commenting again but I still hope it’s something that can be sorted.

With the contributions from all on this great forum it will help me decide the next steps I take. Could be a good few weeks before I get the car looked at.

Thanks again!!
Did you get your ticking noise looked into as mine turned out to be big end bearing failure.



Big ends? I didnt realise they were prone to this failure?
 
  
View user's profile Send private message
   
DAVIDGT996
Trainee


Joined: 24 Feb 2019
Posts: 77
Location: Colchester


PostPosted: Wed Sep 25, 2019 6:55 pm    Post subject: Reply with quote

As Bazhart points out you should see evidence of big end failure in the oil filter if it's on the way out - bronze coloured flakes.

At the 100K mileage mark things can start going south.
_________________
2001 C2 Coupe Tip
Black, GT3 kit, lowered
 
  
View user's profile Send private message
   
deMort
Dijon


Joined: 21 Mar 2015
Posts: 7740
Location: Brighton


PostPosted: Wed Sep 25, 2019 7:13 pm    Post subject: Reply with quote

This is a bit of a different fault in that the car had a full rebuild 15K miles ago .. i doubt its crank bearings in that time Smile

It was also initiated on a comment i made about a different engine .

As always though it's a good idea to have a look at the oil filter or for me mainly the plastic canister for any metal particles that might be present .
_________________
.
My Daughter's Crowdfunding has hit the target .

Thank you all so Very much .

She's not going until july 2020 though .



Mechanic

7pm - 9pm

Indy Mechanic .
 
  
View user's profile Send private message
   
C4Silver
Spa-Francorchamps


Joined: 14 Aug 2019
Posts: 285



PostPosted: Wed Sep 25, 2019 7:50 pm    Post subject: Reply with quote

This has no relevance to diagnosing the fault as there are two experts already commenting.....

Listening to the clips mine does not soumd like that at all,

I'd just like to add that when looking for my 997.1 there were several i looked at with re built engines that made very similar noises to this, and quite a few of the owners said the same thing..... Re built engines all make the same noises....
 
  
View user's profile Send private message
   
bazhart
Approved Trader


Joined: 20 May 2009
Posts: 1004
Location: Bolton Lancashire


PostPosted: Thu Sep 26, 2019 5:00 am    Post subject: Reply with quote

This is such a big and complicated subject that we have written about many times and for which there are numerous contributory factors difficult to isolate.

One technical issue that influences a lot of the causes is to understand that as the engine fires a plug on tickover it initially accelerates the crankshaft and then - some degrees of rotation later - as the next cylinder comes onto compression it slows down again. So within 120 degrees of crank rotation there is a significant speed up and slow down.

The heavier the flywheel the less this "jerk" is felt as the additional weight damps it down and therefore conversely the lighter it is the more it accentuates it. The looser a dual mass flywheel the more it influences how that reacts to these pulses and similarly wear in the torque converter has similar influences..

As engines gradually wear two things happen. (1) a lot of parts become a little more free and loose and the cylinder compression (especially at tickover) reduces slightly. This reduces the pulse strength accelerating the crankshaft but the more free engine can still accelerate quicker than when it was new - so the overall influence on the speed of that rise and drop of acceleration can be greater or lower.

Engines rebuilt with rounder cylinder bores with tighter cylinder clearances, new pistons and rings, reconditioned heads etc can produce powerful tickover pulses like or better than an original new engine but the rest of the transmission and original parts will be looser. So things like hydraulic tensioners (that dampen out the result of these speed variations on camshaft chain snatch) will be less effective - so you simply end up with an engine that would probably be quieter if the tickover speed was slightly raised (since all engines exhibit this tickover problem and the set tickover speed is simply the lowest speed that is expected to eliminate the snatch and allow the engine to be quiet).

As flywheels and gearbox internals wear there is also more slack in those systems so any low speed tickover jerks can result in greater snatch than when everything was tighter and newer.

Because the engine management system alters the tickover speed depending on variables like oil temperatures it can sometimes slightly raise and lower the tickover speed while the car is idling away leading to a ticking noise coming and going as it tries to stabilise things. The speed sender is also not picking up on these speed variations several times during each firing pulse but every 3 pulses and then again after 3 other of the total 6 pulses every 2 revs and so the engine management system is trying to control fluctuations from only measuring some of them and not all of them and therefore cannot always make the right next adjustment to try and smooth them out.

So a well rebuilt engine will have excellent cylinder compressions and performance but because many other internals run more freely than before can generate a tick on tickover that has no detrimental mechanical consequence but is irritating at times.

Thicker oil helps dampen the consequences as does a LTT (for the same reason - lower oil temperature thickens it) etc.

Although it is possible to raise the tickover it can lead to a Tiptronic trying to pull away on tickover (rather than remain stable) and the manual experiencing a less smooth initial clutch grab (similar to the result of fitting a lightweight flywheel).

Therefore, with no downside mechanically, it is usually something best ignored rather than messing with. Happily it does not effect every engine as some have worn differently to others in minute ways that overall make a small difference. Minute changes to fuel injector delivery, temperature sensor values, coolant pump delivery, oil pump tickover performance, oil pressure relief valve leakage, thermostat opening temperatures and rates, valve sealing, tappet hydraulic leak rates etc etc (the list is endless) usually do not cause ticking but every now and again a particular engine just happens to combine a lot of all the downside differences and ticks, while others do not.

Big end failure noises usually increase in strength as the throttle is pressed aggressively and the engine accelerates (revs up) and continue as the revs drop.

Alternatively if the crank is OK then raising the revs from tickover, reduces the time between power pulses (reducing the variation in the magnitude of the snatch between power pulses) and at the same time increase the oil pressure (which helps pump up the various chain tensioners and hydraulic tappets) to help dampen down the noise and the increasing oil pressure usually lags behind the engine revs dropping again so keeps the engine quiet on the rev drop.

big end wear usually is still noisy from earlier on the engine warming up and well before normal running temperature is reached whereas just ticking usually increases in volume after a run when everything is really hot and free and the oil is thin.

So a quick blip of the throttle during warming up will often reveal which source of the noise is the most likely cause.

Baz
_________________
Click here for the Hartech

You can trust us to "CARE FOR YOUR PORSCHE"
www.hartech.org
 
  
View user's profile Send private message Send e-mail Visit poster's website
   
DAVIDGT996
Trainee


Joined: 24 Feb 2019
Posts: 77
Location: Colchester


PostPosted: Thu Sep 26, 2019 7:27 am    Post subject: Reply with quote

deMort wrote:
This is a bit of a different fault in that the car had a full rebuild 15K miles ago .. i doubt its crank bearings in that time .
Mine also had a rebuild at some stage but I doubt only 15K miles ago. Only came to light when the engine was dropped and broken.
_________________
2001 C2 Coupe Tip
Black, GT3 kit, lowered
 
  
View user's profile Send private message
   
bazhart
Approved Trader


Joined: 20 May 2009
Posts: 1004
Location: Bolton Lancashire


PostPosted: Thu Sep 26, 2019 6:29 pm    Post subject: Reply with quote

Bad luck David.

Ironically the most common cause of a noise from the rear nearside is the cam chain tensioner. It is a poor design, no seals, a flat almost all the way down one side, no proper non return valve and the oil feed is at the end of all the oil pressure fed into the camshaft area that leaks out of the camshaft bearing journals, the tappets and the camshaft tensioners. Although you may have oil pressure of around 1 to 1.5 bar at tickover the low revs allow more time for all those oil supply points to leak out and there is along hole at the end of the supply gallery to that cam chain tensioner and at the very end oil flow and resulting end of line pressures will be even lower.

Also the tensioner blade tends to flatten the point of contact with the tensioner itself and this can make the noise louder.

I have reported before that we made some proper ball valve controlled non return tensioners in the very limited space the tensioner enjoys but although some versions worked in some engines it was not sufficiently successful to rely on.

The tensioner on the other side sits the other way up and this helps the crude unsprung "flap valve" to fall under gravity and this helps to retain oil inside it whereas the off side one allows the flap valve (or better described as a plate) to retain oil - so on disassembly one will be full of oil and the other is always empty and with low oil delivery at tickover (after feeding low pressure and low volume delivery to so many other top end parts first) unfortunately this tensioner does not do its job until oil pressure and flow increase with revs.

So after progressively changing all possible parts in a particularly noisy engine (including heads, cams, tappets, tensioners, chains, tensioner blades and fitting special tensioners with proper ball vales and several different return valve springs we still could not isolate the noise completely and have realised since (as a result of building loads of engines) that there are a lot of different causes of the self same noise and it can be non productive to try and find which one applies to which engine and too expensive to change everything and still not solve it.

So I hope the origin of your noise was indeed the crankshaft bearings - good luck with it all.

Baz
_________________
Click here for the Hartech

You can trust us to "CARE FOR YOUR PORSCHE"
www.hartech.org
 
  
View user's profile Send private message Send e-mail Visit poster's website
   
GMG
Nürburgring


Joined: 07 Jan 2018
Posts: 476
Location: Devon


PostPosted: Thu Sep 26, 2019 7:36 pm    Post subject: Reply with quote

...interesting Baz; my recently rebuilt 3.6 engine exhibits this enigmatic M96 'ticking' type noise on the NSR only on a hot engine..recently serviced , with the Indy using Mobil 1...

Having read this I am inclined to drain and refill will Miller's Nano 10w50 to see if this quietens the noise?
 
  
View user's profile Send private message
   
Display posts from previous:   
Post new topic   Reply to topic   All times are GMT - 12 Hours
Goto page Previous  1, 2
Page 2 of 2

 
Jump to:  

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You can attach files in this forum
You can download files in this forum
You cannot post calendar events in this forum