Shadow II engine noise - Rolls-Royce and Bentley Forums
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 12 (permalink) Old 04-11-2012, 08:32 AM Thread Starter
New Member
 
Join Date: Apr 2012
Location: UK
Posts: 7
Shadow II engine noise

Hi - I'm new here so please take it easy on me and apologies for asking the experts for advice straight away but....

My 1979 Rolls Royce Silver Shadow II has recently developed a knocking noise that I can only describe as a clack, clack clack sound - It's quite metallic. It is also engine speed related and only really happens on tickover and low rpm - as soon as the rpm increases the noise disappears. It is also not there all the time and is a LOT more prominent when the car is cold. The noise seems to be coming from somewhere near the centre of the engine under the carbs/intake but I guess the noise could be transferred from many places and very difficult to accurately track down.

I have changed the coolant as it was fairly weak/watery and removed all the belts to rule out any power steering or water pump noises or issues but the noise is still present. I have also since carried out an oil flush and changed all the filters. I only use top quality oil and I have added some Wynns hydaulic tappet additive but it has made no difference.

I believe that theoretically the noise could be either:

- Worn camshaft bearing
- Sticking hydraulic tappet
- Piston slap

Does this sound like a reasonable diagnosis or am I missing something? Are any of these a common problem with Silver Shadows?

Any advice or suggestions would be very welcome.
1979 UK SHADOW is offline  
Sponsored Links
Advertisement
 
post #2 of 12 (permalink) Old 04-11-2012, 11:06 AM
Senior Member
 
guyslp's Avatar
 
Join Date: Aug 2007
Location: Staunton, VA - USA
Posts: 2,919
Your theories are worth checking, but it might also be a bad hydraulic pump (or a hydraulic pump "ticking" its little heart out because of a bad accumulator that can't build any pressure).

It's hard to know exactly what noises actually sound like by written description, so this is just another thing to check.

See Silver Shadow Brake Issues: Your Help Would Be Appreciated! for some information on diagnostics you can perform yourself on the braking/hydraulic system.

Brian
guyslp is online now  
post #3 of 12 (permalink) Old 04-13-2012, 03:08 AM Thread Starter
New Member
 
Join Date: Apr 2012
Location: UK
Posts: 7
Hi Brian, thanks for your reply. I did take the car to the chap who does a lot of the work on it just after it happened and the description of that came back said:

Inspect and report on engine knock/tapping noise?
Noise to be coming from either brake hydraulic pumps, hydraulic followers or even piston knock.
Brake system accumulator no.2 is not holding pressure - two brake pedal pumps and system 2 is depressurised.
Renew no.2 brake accumulator - difficulty with siezed fittings.
Reconnect no.1 brake warning sensor.
Attend to fluid leak from rear hydraulic pump.
Remove pump assembly. Run engine without pump to eliminate possibility of rear pump being cause of noise - No noise improvment found.
Clean complete pump assembly, renew housing seals and reassemble as required. Bleed and top up system.

So I had a big bill, no noise improvment but at least the hydraulic system is in slightly better shape!

I'm a bit stuck now how to diagnose my noise further!
1979 UK SHADOW is offline  
 
post #4 of 12 (permalink) Old 04-13-2012, 06:43 AM
Member
 
Join Date: Feb 2012
Location: Boca Raton
Posts: 33
Worn cam bearings will make you loose some oil pressure to the top,run
The car without the valve cover to see if enough oil gets to the top.
Lifter is a common problem,if this is my car I would change the lifters. That's
Relatively easy to do.
A piston slap is also common on the A bank number 3 and 4.
If you like your car and planing to keep it for years to come consider
A complete rebuild.
mtuerk is offline  
post #5 of 12 (permalink) Old 04-18-2012, 03:37 AM Thread Starter
New Member
 
Join Date: Apr 2012
Location: UK
Posts: 7
Are the valve covers a fairly easy job to remove? I did consider taking them off to have a quick look underneath and using the opportunity to change the gaskets as they leak on one side but they looked like a real pain to get to without removing a lot of parts, maybe all of the intake?

Please could you let me know what exactly I would be looking for if I do take tghe plunge and the covers were removed and how I can tell if it's the lifters making the noise?

I like my car a lot but unfortunately a complete rebuild is just not on the cards right now, I'm not even sure it would make financial sense but she's a lovely thing so I would like her to run as she should.

Thanks for the advice BTW.
1979 UK SHADOW is offline  
post #6 of 12 (permalink) Old 04-20-2012, 03:25 AM
Phantom
 
Hemmo's Avatar
 
Join Date: Jul 2010
Location: The Netherlands
Posts: 235
Send a message via MSN to Hemmo
Quote:
Originally Posted by 1979 UK SHADOW
Are the valve covers a fairly easy job to remove? I did consider taking them off to have a quick look underneath and using the opportunity to change the gaskets as they leak on one side but they looked like a real pain to get to without removing a lot of parts, maybe all of the intake?

Please could you let me know what exactly I would be looking for if I do take tghe plunge and the covers were removed and how I can tell if it's the lifters making the noise?
The covers can be removed, however there's not a lot of space.
Extra attention you need when replacing them as the new gasket shouldn't fall out of it's place.

I think you have lifternoise same like me...how many miles ?
i suggest oilchange with thinner oil may solve the problem; at least for the money it's worth the try.
I want to do it myself, but haven't had the time (and good mood) to do it yet.


Could it be a little more perhaps......no, it MUST be more!
Hemmo is offline  
post #7 of 12 (permalink) Old 05-07-2012, 03:08 PM Thread Starter
New Member
 
Join Date: Apr 2012
Location: UK
Posts: 7
The mileage has just clicked over past 110k so she's no spring chicken but in some way I prefer a car that has had some use rather than sat still for long periods.

I was trying to figure out the thin, thick oil debate. When the car first started making the noise it had cheap oil in it, correct grade but seemed thin & watery (I think it was a brand such as Comma) so when the noise appeared I used a good quality engine flush then changed the filters, plugs, distributor cap and oil to good quality oil (Morris). I also added a couple of cans of hydraulic tappet treatment but it has had no affect.

I had a good listen to it earlier using a piece of pipe as a stethoscope and I'm pretty sure the noise is coming from the right bank and from the rear of that (closest to the driver) so I think I'm going to remove that cover when I get a free weekend and have a good look. The noise completely disappears when the rpm increases then returns when the engine ticks over of is at low rpm.

If I remove the valve cover, please can someone tell me how can I tell if it's a sticking tappet?
1979 UK SHADOW is offline  
post #8 of 12 (permalink) Old 05-07-2012, 03:40 PM
Senior Member
 
Join Date: Oct 2010
Posts: 217
Quote:
Originally Posted by 1979 UK SHADOW
The mileage has just clicked over past 110k so she's no spring chicken but in some way I prefer a car that has had some use rather than sat still for long periods.

I was trying to figure out the thin, thick oil debate. When the car first started making the noise it had cheap oil in it, correct grade but seemed thin & watery (I think it was a brand such as Comma) so when the noise appeared I used a good quality engine flush then changed the filters, plugs, distributor cap and oil to good quality oil (Morris). I also added a couple of cans of hydraulic tappet treatment but it has had no affect.

I had a good listen to it earlier using a piece of pipe as a stethoscope and I'm pretty sure the noise is coming from the right bank and from the rear of that (closest to the driver) so I think I'm going to remove that cover when I get a free weekend and have a good look. The noise completely disappears when the rpm increases then returns when the engine ticks over of is at low rpm.

If I remove the valve cover, please can someone tell me how can I tell if it's a sticking tappet?
Removing the valve covers doesn't gain access to the tappets they are in the middle of the 'V' and require removal of the carbs and inlet manifold, not as daunting as it looks, Tappets can then be removed and tested easiest way I know is to use a push rod in the top of tappet and push down to see if it holds pressure against you pushing if not it can be stripped out and cleaned, then rebuilt and retested. If still no good then it would need replacing, I believe there is an american tappet that is a good replacement. sure someone on here would be able to help with that. Another thing to check is brake pump noise, easily tested, pump brake pedal until pressure lights on, remove reservoir tops first and cover over with rag to stop brake fluid going everywhere, then start engine and listen for noise, this would disappear when pressures up
rollmech is offline  
post #9 of 12 (permalink) Old 05-07-2012, 04:36 PM Thread Starter
New Member
 
Join Date: Apr 2012
Location: UK
Posts: 7
Hi, thanks for the reply. Yes, I knew that by removing the valve covers will not give you access to the tappets but I was hoping that you may be able to push the push rod into the tappet as you said to see if it holds pressure or if it's stuck - Is this possible?

If this is possible then at least I know what I am dealing with & can think about the next step.
1979 UK SHADOW is offline  
post #10 of 12 (permalink) Old 05-07-2012, 05:03 PM
Senior Member
 
Join Date: Oct 2010
Posts: 217
Quote:
Originally Posted by 1979 UK SHADOW
Hi, thanks for the reply. Yes, I knew that by removing the valve covers will not give you access to the tappets but I was hoping that you may be able to push the push rod into the tappet as you said to see if it holds pressure or if it's stuck - Is this possible?

If this is possible then at least I know what I am dealing with & can think about the next step.
Guess should be possible if you can get enough push on the pushrod, never tried it myself but see no reason why you shouldn't be able to
rollmech is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Rolls-Royce and Bentley Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome
 

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.

SEO by vBSEO 3.6.1