| Author | Message | ||
     Peter Maclaren Yet to post message Username: ludo Post Number: 1 Registered: 4-2009 |
The engine noise of my 1988 Spirit (chassis No SCAZS00A3JCH22650) as heard within the car, is I believe, excessive. My previous car,a 1974 Shadow was much quieter. The car is New Zealand new and appears totally original,except for the mufflers which I have had replaced with genuine RR parts. The noise is particularly harsh under acceleration.when the'beat'of the V8 is most intrusive.I suspected some part of the exhaust system contacting the sub frames but have found nothing, The exhaust system is totally S/S , and I am wondering if this is original, as I have read where the 'downpipes' were mild steel and the rest of the system was stainless. A Jaguar I owned some years ago was converted to s/s and this resulted in quite an increase in noise. Perhaps this is normal noise for a Spirit,but it seems unlikely.In every other respect the car is satisfactory. I would be grateful for any advice as I have 'run out of ideas. | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1117 Registered: 4-2003 |
Peter The SZ cars had trouble with their engine mountings particularly the rear ones. I have seen them both sheer off and the only thing that stopped the engine rotating in the body were the mounting bolts against which the casting jammed. You might also have a good look at the sub frame mounts particularly the left rear which cops a steady dribble of LHM which rots the rubber. From underneath you can see whether the central support tube, normally suspended by rubber, this can descend until it rests on the body support! | ||
| Peter Maclaren New User Username: ludo Post Number: 2 Registered: 4-2009 |
Thank you for responding Bill,I have inspected the points you mention and all appear OK. When I purchased the car I contacted the RR specialist in Auckland who recommended the car as being in very good condition, and that ,unusually ,it was 'bone dry' underneath.My local RR service firm have had the car on their hoist and believe all is OK,and that the interior noise was"about average'.The sound does diminish a little once the car is hot ,and it is an 80k run to his premises. I can,t believe Crewe built cars to be noisier than their predecessors. I have gutted the interior carpets and soundproofing looking for any missing plugs etc to no avail.I have even installed more soundproof material. The engine noise inside is only apparent when the car is accelerating, and is normal when it is stationary. | ||
| Lluís Gimeno-Fabra Frequent User Username: lluís Post Number: 82 Registered: 8-2007 |
Hi Peter, Indeed I also experienced an increase of noise when "improving" the system to be fully stainless in other makes of cars (Jaguar, Mini, Fiat and Lancia) but I would have said the noise increased pleasingly (sporty roar), but of course this might not be what you are looking for in a Royce... Best regards Lluís | ||
| Peter Maclaren New User Username: ludo Post Number: 3 Registered: 4-2009 |
Hi Lluis, the sporty roar is not 'out of place' on a Jaguar, but I prefer my RR to be as quiet as possible, at least on the inside. It has been suggested to me that I could apply fibreglass exhaust wrap to the downpipes to reduce reverberation. I understand that its normal purpose it to reduce underbonnet temperatures,so I don't know whether it would have the desired effect, and if it would have an adverse effect on the rest of the exhaust system Any comments would be appreciated. | ||
| Lluís Gimeno-Fabra Frequent User Username: lluís Post Number: 87 Registered: 8-2007 |
Hi Peter, It's graphite combined with fiberglass apparently. I think you might like this link in case you plan to install it yourself (he does it for the exhaust manifold, but the installation should be the same for the downpipes anyway): http://www.mx6.com/forums/2g-faq-performance/193934-how-exhaust-wrap-heatwrap.html I asked a friend who did this in a very different car, a tiny (but very high performace)cooper mini. Apparently the following result was obtained: Heat transfer to the surroundings was greatly reduced BUT: a) Hardly any difference in noise. b) LOTS of trapped moisture. Of course it dried fast when starting, but the problem was during storage. Stainless Steel does not like salty moisture. Not sure if this helps, but at least it is the little that I know... Cheers Lluís | ||
| Peter Maclaren New User Username: ludo Post Number: 4 Registered: 4-2009 |
Hi Lluis,thanks very much for finding out so much about exhaust wrapping. I have purchased a roll but am a bit reluctant to apply it as the downside would seem to outweigh the benefits. I made a bit of a discovery in that the parts man at our only distributor in the South Island of NZ, suggested looking at the chrome finisher on the rear muffler. He said he had experienced a simmilar problem on a car of his (not an RR) where the exhaust somehow buffetted the bodywork behind the bumper, and moving the finisher further rearward made a difference. Mine appeared to be in the correct position according to the manual, but I slid it about 50mm out, then took the car for a run and 'lo and behold' it was much improved, although of course the finisher was now level with the outer edge of the bumper . The next discovery was that the rear muffler although it looks like the correct part UE 70150, it has part no UE 70321 embossed on it. I have studied the parts manuals and can't find any car with a muffler carrying this number. I am now wondering if this is a substitute part, that is not matched to the rest of the system. and is contributing to my problem. I am finding these forums of great interest ,and have spent many hours reading the entries.It is a great way to find out more about the cars from folk who already experienced most of the problems and so generously give their time to assist others. | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 345 Registered: 6-2006 |
Peter, just a word about the part numbers, often the number on the box seems to be literally the box number. Left and right can have the same number on, even though they have obviously different pipes leading in and out, but the boxes are the same. Not sure if that applies to yours though. | ||
| Peter Maclaren New User Username: ludo Post Number: 5 Registered: 4-2009 |
Thanks for that Paul,these part numbers can be confusing.Under the heading 'Genuine Replacement Parts'on the Australian club site, my rear muffler is listed as RH 12270,whereas on a CD I purchased some time ago its listed as UE 70150. The one on my car is different again as UE 70321.IT also has additional inscription which doen't appear on the new 'genuine' front front muffler which came from Crewe last year.I will try and upload a photo,but if it fails the inscription reads'C&W RR-M LTD, sorry about picture quality, its hard to get a clear picture lying on the floor of my garage and endevouring to minimise reflection | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 346 Registered: 6-2006 |
Peter, that does sound like it's a box part number. | ||
| Peter Maclaren New User Username: ludo Post Number: 6 Registered: 4-2009 |
Paul, It would seem that different part manufacturers must have different codes for identifying the same part.My car (22650) should have either UE 70150 or RH 12270 from what I can determine. Just to be different it has UE 70321, a number I can't find anywhere, although the UE series seems appropriate. At least I have now determined that the excessive noise is coming from the rear of the car and not the front.From the driving position I was positive it was in front of me.  | ||
| Peter Maclaren New User Username: ludo Post Number: 7 Registered: 4-2009 |
I thought I had solved the problem of excessive noise inside my car 22650, but I was wrong and its still irritating me. I have been following the recent discussions re keeping cars original with great interest,particularly as mine seems a little deficient in places. While checking the air filter I noticed a short section of plastic pipe molded to the filter housing. It looked like it should be connected to something but wasn't. On studying the online manual for the car Section J2 'Air intake system' I read that it is used to vent the air injection system into the air intake system. The parts diagram shows a hose but doesn't indicate what it is connected to. Also mentioned is that naturally aspirated engines have a black plastic diffuser fitted into the ducting in front of the cast aluminium intake elbow. It goes on to say that this is to eliminate the resonance or noise generated within the system at low engine speeds. My car is minus this as well. It may be a 'long shot' but I am wondering if the absence of these parts is contributing to the noise I am hearing inside the car. It is mainly when I am driving around the city that the noise is most apparent whereas on the open road it is quite acceptable. Perhaps I am striving for the unattainable, but like most owners I believe that they are excellent cars and that everything on them is there for a reason.I would be grateful if someone can enlighten me as to whether their car is fitted with the parts I appear to be missing | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 387 Registered: 6-2006 |
Peter, there should be a plastic baffle about 12" long *inside* the flexi rubber air intake tube/trunking. About in the middle. Not sure how to describe it - maybe a little like an old Klaxton horn? If that is missing, it would cause some extra noise. "I noticed a short section of plastic pipe molded to the filter housing." Is it blanked off? I think they use a generic air filter housing, but that should be closed. (If it's the one I'm thinking of) | ||
| Peter Maclaren New User Username: ludo Post Number: 8 Registered: 4-2009 |
Paul, thanks for your response, you are of course right on both counts.The baffle is indeed just where you said I should find it, it helps if you take the ducting off at both ends before claiming that it is empty. The plastic pipe is blanked off but that wasn't obvious until I removed the air filter. This means that firstly I have wasted your time, for which I am sorry and secondly I am no nearer to solving my problem. As I note from other contributors to the forum, perseverence is essential so I'm not giving up yet. Thanks again for your help. | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 390 Registered: 6-2006 |
Peter - much stranger things have happened and gone missing. |
