Re: [doc] Jaguar O/T; USA V8 engines had problems due to sulfer in petro
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [doc] Jaguar O/T; USA V8 engines had problems due to sulfer in petrol
- From: Packodenton@xxxxxxx
- Date: Mon, 13 Jun 2005 09:35:23 EDT
The USA version of the Jaguar V 8 engine suffered from the terrible fate of
the early 1990's BMW V 8 engines. The engine article below is from a BMW V 8
specialist, however it applies to the same problem that Jaguar had with their
USA V 8.
What's wrong with the V8?
September 19, 2004 The original "What's wrong with the V8?" article was
written in 1997. It's time for an update.
First, let me make it clear that any and all warranties on this engine are
long over. The 6yr 100K mile warranty ran out some time around 2001. Don't
expect BMW to come to your aid if you have a problem, it's not their fault that
previous owners of your car didn't act on the chance to have the problem
corrected.
An important point in the Nikasil issue that has become quite clear over the
last couple of years is that it's really not an issue any more. BMW, for the
second time in history, succeeded in forcing a change in US fuel production.
Some time around 1997/1998, the US fuel companies cleaned up their fuel,
removing the large amounts of sulphur that had been commonplace before then.
If you are considering the purchase of an M60 equipped vehicle, you should
have it checked to see if it has a Nikasil or Alusil engine. If it has a
Nikasil engine, you should have a leak down test performed. If that leakdown test
shows results below 15% on all cylinders, you should not consider the engine
to be a problem. If the engine has not failed, it probably will not fail due
to the new fuels.
We personally have seen Nikasil engines with 30K+ miles on them with 4% or
less leak down, because the engines were installed at or about the time that
the fuel changes took place.
Read the original, unedited article below, determine the engine, have the
leak down test performed if necessary, and make your own decision. Original
Article.
BMW released the M60B30 and M60B40 V8's with the 93 model year 5,7 and 8
series. These engines ran until the 95 model year. From the 96 model year, they
were replaced by the M62B44. The 3.0L was dropped in the US, but the rest of
the world got the M62B35, a 3.5 litre V8.
There are many rumours about the fate of the M60 engine, but only one is
true. The engines have been known to suffer damage to the cylinder bores from
the excessive amounts of sulphur in the US fuels.
The blocks are made of Nikasil, which is Aluminum impregnated with Nickel
and Silicone. Apparently , sulphur reacts adversely with the Nickel , causing
very slight blemishes in the top few millimetres of the cylinder bore. The
cylinder bores are crosshatched, which is the name given to a pattern scratched
into the surface of the cylinder wall. These scratches help seat and seal the
piston rings, allowing good compression.
When the cylinder walls become damaged, the piston rings can no longer seal
properly. As a result, the engine suffers from "leak down". This is the term
given for the amount of air that can escape past the piston as it attempts to
compress the air into the combustion chamber. A near new engine , in good
condition, should have a leak down rating of approximately 5-8%. BMW's maximum
allowable leak down , on any engine, is 15%. Anything beyond that requires
repair to the engine.
Leak down can also be caused by poorly seated valves.
The problem in the V8's manifests itself as an EXCESSIVELY rough idle. These
engines, due to their performance oriented cam shafts, have a noticeable
"rock" at idle, this is completely normal. However, excessively rough idle will
cause the entire car to shake, usually unevenly. The problem can also cause
the engine to lose so much compression that it will no longer start.
While BMW was investigating the cause of the problem, several different
methods of repair were tried.
First, they decided to raise the operating temperature of the engine, in an
attempt to get a better burn of the gas, and therefore lessen the damage. The
benefits of this campaign , which included replacement of the engine EPROM
and thermostat, were negligible, if existent. However, they were an attempt to
fix a problem that was not yet fully understood.
Once it was decided the engines needed to be opened and repairs made, the
first try was installation of new pistons and rings, this was only tried on a
few engines and was immediately dismissed as not viable.
Next step was to replace the short block assembly. This is what is still
being done now, however, until the problem was 100 percent diagnosed by BMW, the
replacement short blocks were of the same material as the original engines.
This was not so much an oversight, but the only possible way of keeping cars
on the road until a permanent solution could be found.
As a measure of good faith, BMW initiated an engine warranty, covering all
internally lubricated parts, which includes the short block, for 100,000
miles, or 6 years. Until this, the engines were only covered under the standard 4
year 50,000 mile warranty.
Now, as the short blocks were being replaced with the same exact part,
future problems could be expected without a doubt. The result of this situation is
that some cars have had 2 and even 3 short block replacements.
As of early 1997, all replacement short blocks were of the new material,
called Alusil. This material has been used in the V12 engines since their
inception. No reason was given for the change to Nikasil, but I'd like to bet that
guy no longer has a job. Anyway, Alusil does not suffer the same problem as
Nikasil and if the Alusil short block has been installed, you no longer need
to worry about the situation.
How do you tell which material is in your short block ? That part is fairly
easy. But it requires getting under the right front of the car. All M60 and
M62 blocks have casting numbers on the right side, directly alongside the 3rd
cylinder, slightly above the coolant drain bolt.
These are the casting numbers to look for:
Nikasil M60B30 1 725 970 or 1 741 212
Nikasil M60B40 1 725 963 or 1 742 998
Alusil M60B30 1 745 871
Alusil M60B40 1 745 872
Alusil M62B44 1 745 873
NOTE, all US market M62 engines are Alusil.
This is the only way to determine which M60 you have, short of removing a
cylinder head.
In performing engine repairs or rebuild procedures in the future, it is
imperative that you correctly identify the cylinder block, as the pistons and
rings used in each style are different and not interchangeable.
What do I do if my engine idles rough ?
If you feel your M60 is idling roughly, make an appointment with your dealer
for an idle quality check. This check is free, under the conditions of the
100,000 mile engine warranty. During this test, the technician hooks the car
up to the BMW diagnostic computer system, which monitors the condition of the
engine. If, during this test, the computer finds that there is a potential
problem, it will order the technician to perform a manual leak down test. If
the tech finds any ONE cylinder to have more than 15% leak down, you will be
advised of the need for a new short block. You will then be requested to either
leave the vehicle, or make an appointment to bring the vehicle back. The
dealer will require the car for approximately 5 days, during which , they are to
make a rental or loaner car available to you. If you have the test
performed, but the results do not show the need for a new engine, do not go running to
the next dealer for a new test. The dealer gets paid by BMW for his time,
however, repetitive testing will not be covered, so the second dealer will not
get paid for his time. This is unfair to the dealer. If your car passes, but
you feel it should fail, take it in for another test in a few months, not
straight away.
In a message dated 06/13/2005 8:46:49 A.M. Eastern Daylight Time,
chrisparnham1@xxxxxxxxxxxx writes:
It depends how much it is. The 6 cylinder models just keep going, but
190K miles is a lot! The V8's ( like I currently have) can be a bit
troublesome. Good xj6's are available for a few grand.
Best regards
Chris Parnham
DOC 2
RHD vin 5638
BTTF vin 20049
-----Original Message-----
From: doc-uk@xxxxxxxxxxxxxxx [mailto:doc-uk@xxxxxxxxxxxxxxx] On Behalf
Of ibolden@xxxxxxx
Sent: 12 June 2005 12:32
To: doc-uk@xxxxxxxxxxxxxxx
Subject: [doc] Jaguar O/T
Hi Group,
Apologies for the off topic post, but due to the wealth of knowledge out
there I thought it would be worth asking.
Does anyone have any knowledge of Jaguar XJ's, especially high mileage
ones?
I've seen a lovely 1996 Sovereign at a very cheap price but she has 190K
on
the clock. Usually I wouldn't necessarily be put off by this, but the
dealer
is classing it as a "trade sale" which basically means it's sold as
seen, i.e.
he's not going to service it or put on a set of new rear tyres, he
won't
even MOT it etc, etc.
Is there anything in particular i should be looking out for or be
worried
about?
You thought's are appreciated.
Ian
DOC 316
NOTE: THIS DOCUMENT MAY CONTAIN CONFIDENTIAL AND NONPUBLIC INFORMATION. IT
IS INTENDED ONLY FOR THE USE OF THE INDIVIDUAL(S) OR ENTITY(IES) NAMED
ABOVE, AND OTHERS SPECIFICALLY AUTHORIZED TO RECEIVE IT. If you are not the
intended recipient of this document, you are notified that any review,
dissemination, distribution or copying of this communication is prohibited. If you have
received this communication in error, please notify me immediately by return
email, delete the electronic message and destroy any printed copies. Thank
you for your cooperation.
[Non-text portions of this message have been removed]
DOC UK Website: www.deloreans.co.uk
Unsubscribe: doc-uk-unsubscribe@xxxxxxxxxxxxxxx
** Unless otherwise stated, all messages posted to the group are assumed public and may be printed in the club magazine **
Yahoo! Groups Links
Back to the Home of PROJECT VIXEN