Last post on Sep 16, 2012 at 10:07 AM
You are in the BMW 7-Series
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BMW 7 Series
#999 of 1317 some answers
Jan 15, 2004 (11:19 am)
regarding tire rotation, BMW does not recommend tire rotation on any of its cars, as far as I know. I'm not sure why.
Tire mfg's, on the other hand, generally insist on tire rotation if you want to maintain the mileage warranty.
Regarding a "720iL" V8, there is not and never has been such a car. The last two digits indictate the engine's liter displacement, i.e., a 745 has a 4.5 liter engine. A 720 would have a 2.0 liter engine. The only 2.0 liter BMW engine is a 4 cylinder.
Back in the early 80's you could get a 720 in Europe--a full sized sedan with the tiny 2.0 liter 4 cylinder engine. Never made it to the US for obvious reasons.
Only 1989 7 series models were the 735 six cyl and the 750 v12.
warning: the 1993-1995 740 V8 had a "nikasil" engine which was defective. Avoid this car unless the engine has been replace with an "alusil" engine. don't trust the dealer to properly inform you on this issue.
#1000 of 1317 Thanks for the warning, f1
Jan 15, 2004 (1:18 pm)
"warning: the 1993-1995 740 V8 had a "nikasil" engine which was defective. Avoid this car unless the engine has been replace with an "alusil" engine. don't trust the dealer to properly inform you on this issue."
Wow.....that's reassuring! I thought this kind of stuff only happened to Oldsmobile,,,
Jan 15, 2004 (5:33 pm)
In an earlier post someone said BMW sweeps the big problems under the rug. Nikasil was one of them. Eventually, BMW was forced to extend the warranty to 6yrs/100,000 miles, but that warranty now is gone and a lot of engines never were fixed.
The problem is that the cylinder walls corroded in the presence of high-sulpher US fuels. Lots of used car dealers out there are selling nikasil V8 740's, asking top dollar and not even aware of the problem.
1995-98 Jag V8 has the same problem, but apparently to much less of a degree.
Jan 15, 2004 (7:14 pm)
Hmmmm, I thought the Jag V-8 came out in 98. No?
Jan 16, 2004 (9:50 am)
you may be correct. 1995 was clearly wrong on my part. can't recall if the v8 came out in 98 or 97, so now I'm mixed up on whether the 99 v8 is nikasil. a jag expert would know more. I'm sure the 1998 has the problem because one of my friends has a 98 XK8. apparently the plastic guides for the timing chain also are suspect on the early v8's (his literally blew apart a couple months ago, but fortunately there was no collateral valvetrain damage).
Jan 17, 2004 (11:35 am)
Well, ok then, I will definitely steer clear of the 98 either way. Thanks.
Jan 26, 2004 (6:20 pm)
>> The problem is that the cylinder walls corroded in the presence of high-sulpher US fuels. Lots of used car dealers out there are selling nikasil V8 740's, asking top dollar and not even aware of the problem.
Threads like this are a good example of how misinformation gets spread around on these boards and eventually accepted by many as truth.
There was a problem with the 1995 4.0L and high-sulphur fuel in some southeastern states. Here in California the problem is non-existent. Yet, dealers and private sellers are asking anything BUT top dollar. They are practically giving away 1995/1996 740-series.
Any 1995 740 that has not had Nikasil-related engine problems to this date never will. A clean, well-running '95 could be the ultimate 740-series bargain.
#1006 of 1317 misinformation
Jan 27, 2004 (4:45 pm)
well, misinformation certainly gets spread around all right. Where did you get yours?
The Nikasil V8 was intoduced in 1993 and infected all 1993 and 1994 e32 v8's. BMW extended the warranty on all of these cars to 100,000 miles and 6 years. I can personally vouch for that because when I shopped a 1993 V8 in 1997 the salesman made a big deal about the extended warranty, and the service manger quietly warned me away from the V8 because of the known, nikasil issue.
Yet somehow you think the problem was limited to 1995.
as for the idea that it is limited to the southeast, I personally know people in the Northwest whose V8 blocks were replaced under warranty due to nikasil corrosion of the cylinder walls. Or maybe BMW was just giving away free engine blocks for the heck of it?
more info on the problem can be found at numerous web sites which, unfortunately, Edmunds will not let me give links to ("competing" sites). I'll just say that on one very active BMW 7-series board, we get at least one poor fool a month who just bought a nikasil 740 and now is realizing that rough idle will not be fixed by a "tune up."
Whether a 4.0 block is nikasil or alusil can be determined by examining the serial number. Due to the link problem, any interest person will have to Google for a list of serial numbers to stay away from.
Jan 28, 2004 (3:51 am)
So THAT's the reason for the rough idle, eh?
#1008 of 1317 Nikasil V8 Problems?
Feb 02, 2004 (6:04 pm)
I have a 1994 BMW 740iL that I have owned for 7 years with the original Nikasil V8 engine. It currently has 60,000 miles on it with no hint of idle problems associated with sulfur in the fuel damage to cylinders of this particular engine alloy. I have always used AMOCO - now BP - Ultimate premium fuel because of it's low sulfur content. I live in Iowa. I personally think that a Nikasil V8 engine that has lasted this long with no idle/compression problems probably will last OK into the future because the fuel refiners are reducing the sulfur content in the fuel more and more under federal regulations as time goes on.
Any other opinions on this?