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joe_capp
06-18-2012, 10:33 AM
At some point, everyone is a newbie, that includes me.

I have a purchase offer that is contingent on a pre-purchase inspection (PPI) for a 05
545i that is loaded with every package and option minus the Active Cruise and HUD. For months I have researched through this forum and others for known issues on 5 Series vehicles, maintenance costs etc. You don't purchase one of these fine automobiles without the expectation that you will have (potentially) high out of pocket cost for up-keep; I'm prepared for that and go into the sale knowing that.

The vehicle has 76K miles (majority Hwy), I have all the service history, and it was maintained very well by the previous two owners at a BMW dealerships. My question is regarding the pre-purchase inspection which is a condition of the sale for me. I have the option of a PPI with an engine compression test at an extra cost of $100. In the big scheme of things, $100 is almost a drop in the bucket for the added assurance that there is nothing majorly wrong with the engine.

I give the Germans all the credit in the world for their bullet proof motors, but this is a V8 vs an I6 and seems to me the extra $100 is worth the expense.

Would anyone disagree?

Thanks in advance from the newbie.

bimmerfan52
06-18-2012, 04:16 PM
IMHO a waste of time.

If you ask the owner to allow a cold start (feel engine is cold with your hand before starting) and it doesn't blow dark smoke there should be reason to believe that an engine with 76k and reasonable maintenance would have ring or cylinder problems.

Regarding giving credit to the Germans for bullet proof engines you are talking about the N62 - one of the worst engines BMW has produced in the last 20 years with respect to leaks. I know - I own one - more leaks than a retirement home. If your gaskets are in good condition you have a fighting chance. You will still spend money in the next 20-30K miles, just a question of how much.

Crucial is if the engine was maintained strictly according to BMW dealer's CBM which dictates 15K between oil changes. This causes sludge buildup and results in very acidic oil as fuel escapes past the rings on start up and mixes with the oil, getting more concentrated as the oil gets older. Acid is deadly to gaskets and seals.

Make sure all of the oil seals (upper and lower timing chain covers, valve covers, oil pressure sensor and especially the alternator bracket gasket) are closely examined by someone who knows what to look for.

Next are coolant leaks, especially the valley pan gasket and coolant pipe (in the valley pan). These can cost a wheelbarrow full of cash to fix. Full examination of the coolant system is in order, including hoses and reservoir tank as if the engine overheats it can be deadly to the aluminum block and can wipe out gaskets as components over-expand under heat stress.

The transmission Mechatronic sealing sleeve and sump pan should also be closely examined as these is common leak points.

The steering rack with active steering components and the active roll stabilization components on the sway bar should also be examined for leaks. The steering rack alone is $3K (re-manufactured unit) and replacement labor ranges from $700 - $1200 depending upon who is beating you up.

Who is doing your PPI? It should be a very trusted Indy or dealer with lots of BMW experience that knows what to look for.
Alarm bells go off when I hear $100 for a full compression test on the N62 engine. Two months ago I changed the plugs on my 2004 545i and can tell you that working carefully and methodically it is nothing to spend 30-60 minutes each on the #4 and #8 plugs that are against the firewall, as components need to be removed in order to get at these plugs. Master wrench turners with N62 experience can do a full set of plugs in 60-75 minutes, but no master wrench turner will charge you $100. If you feel confident of the inspector's abilities and the owner will allow a stranger to tear apart their engine to do the compression test (I wouldn't), by all means throw a new set of plug in while they are doing the compression test (my set of eight OEM Bosch cost $24 after rebate from Amazon last month). It will be the cheapest spark plug change you have ever paid for. Ask a dealer or good Indy to quote what a spark plug change on an N62 costs and you will see what I mean - keep in mind that a spark plug change includes no time to screw in the probe for the compression test, turn the engine over and record results.

If the car was under an extended bumper to bumper warranty you can relax a little bit as any dealer will diligently search for work each time the car comes into their garage. You may see many of the items I have mentioned if you have examined the service records.

Good luck. I hope the sale turns out well for you. I absolutely love my 545i. Gobs of power and a very wide power band - 70-80% of 330lb-ft maximum engine torque is available from 1800-5000 rpm. And with the active roll stabilization it is a monster to drive and have fun with. The 545i can be acquired very economically - just proceed with caution as a good buy can turn into an expensive nightmare if the past maintenance wasn't done properly and/or issues are missed during the inspection.

joe_capp
06-18-2012, 06:02 PM
I sure appreciate all the help and advice on the way ahead with this 545, it's a heck of a car and I'm very interested to be the eventual owner.

This car has had all maintenance performed at a BMW dealership during it's existence. Oil changes were like clockwork every 15K and all required maintenance was kept up by the previous owners. All the work was done under factory and extended warranty and the second owner purhased it as a CPO, and again, all inspections and maintenace performed on time and at a BMW dealership.

I'm having the PPI done at BMW of Sterling, VA which from my discussions with folks in the Mid-Atlantic Region forum are very reputible. Two close friends only take their M5's to this dealership over much closer dealerships based on their service experience and reputation, so I guess I have a "warm fuzzy" that the PPI is being conducted by someone with a good track record.

I will be sure to emphasize the items you mention with respect to leaks when I show up for the PPI. I'm not sure if I would be getting what I pay for or not with the extra $100 on the compression test based on your experience changing plugs, meaning the time involved, but I will inquire as to how much time they will need for the entire PPI and see what that may tell me.

I hope this works out as well - it's a beautiful car and I would love to own it and enjoy driving it.

Thanks again for your help.

bimmerfan52
06-18-2012, 06:46 PM
I sure appreciate all the help and advice on the way ahead with this 545, it's a heck of a car and I'm very interested to be the eventual owner.

This car has had all maintenance performed at a BMW dealership during it's existence. Oil changes were like clockwork every 15K and all required maintenance was kept up by the previous owners. All the work was done under factory and extended warranty and the second owner purhased it as a CPO, and again, all inspections and maintenace performed on time and at a BMW dealership.

I'm having the PPI done at BMW of Sterling, VA which from my discussions with folks in the Mid-Atlantic Region forum are very reputible. Two close friends only take their M5's to this dealership over much closer dealerships based on their service experience and reputation, so I guess I have a "warm fuzzy" that the PPI is being conducted by someone with a good track record.

I will be sure to emphasize the items you mention with respect to leaks when I show up for the PPI. I'm not sure if I would be getting what I pay for or not with the extra $100 on the compression test based on your experience changing plugs, meaning the time involved, but I will inquire as to how much time they will need for the entire PPI and see what that may tell me.

I hope this works out as well - it's a beautiful car and I would love to own it and enjoy driving it.

Thanks again for your help.

I'm shocked that a BMW dealership would do a complete compression test (all eight cylinders) for $100.
Even if you add a dealer's plug prices which can be $12-$20 per plug (they won't put your parts in) it would still be a steal if you could talk them into putting in new plugs after they test each cylinder (assuming everything else looks good first). You're taking a chance, (but not a big one) that one or two of the compression readings don't match the others - but if it were my potential purchase I would have them throw in the plugs. I did mine at 82K miles and it made a big difference in response.

The 15K oil changes "like clockwork" are not good - way too long to keep oil in the engine, but it is what it is. You can start on a new maintenance plan of every 5K-7K between changes after you buy it.

Best of Luck and update us if you decide this is the one!

joe_capp
06-18-2012, 07:13 PM
I was cautioned from others on the every 15K oil changes, but like you said there's not much I can do about that other than to change the intervals if the car comes my way. I have nothing to lose in asking the dealership to install the plugs during the compression test, so I will call and ask if they will do that for sure.

I'll keep you posted, I've been looking for this type 5 series for quite some time and I hope it all works out.

Thanks again.

Damon54
06-19-2012, 07:34 AM
$100 could potentially save you thousands. Even better deal if you could get them to change the plugs!

This particular BMW V-8 ( N-62) has hardly proven itself to be "bulletproof". I would offer them $1500 more if they would fix the leaking Vally pipe under the intake manifold issue.

dolfan13
06-19-2012, 09:01 AM
I would say valve seals are the biggest problem with these engines.I redid mine and changed all gaskets.Let car get fully warmed up,let idle for at least a min then stomp on the gas pedal.If no smoke valve seals ok.That said would have wanted a 550i but still awesome car,even better with sport package.Dont buy a 545i without it!

joe_capp
06-19-2012, 11:34 AM
I contacted the BMW Dealership who is doing the PPI. I asked about the possability of changing the plugs while they were doing the compression test, and the Service Advisor informed me that would be difficult given they only check one cylinder on the compression test; I guess that explains the cost of only $100.

The Service Advisor said (in his opinion) that the compression test on one cylinder as part of the PPI at a cost of $100 was not worth the money. What they would likely find on the compression test they will see in other diagnostics they are running in the "base" PPI that would give indications of anything abnormal that I should be concerned with.

Additionally, there was nothing in this vehicles service history (he pulled real time while we were talking) that stands out as a red flag that would warrant the compression test. He was sure to inform me that it was my decision, but if I was asking his professional opinion (which I was), he didn't feel the compression test was necessary.

So, am I being led down a wrong path in your view, or does this align with what you folks would also recommend?

Damon54
06-19-2012, 01:52 PM
Perhaps not worthless if you can choose the specific cylinder is to be tested.
I think info is out there that should give you an indication as to which have caused the issues.

Cylinder 5 & 8 are the usual culprits, I think.

bimmerfan52
06-19-2012, 03:37 PM
For a correct compression test all cylinders are tested and any significant variation on the low side of an individual cylinder points to compression loss.
Testing one cylinder tells little, unless the cylinder you happen to test is so low that experience tells you something must be wrong at that low a reading. If the compression in that cylinder is so low, chances are examination of how the engine runs and its exhaust output will have already signaled a problem.

If you test just #5 and it is OK, does that mean #8 is also OK without testing it?

Generally compression tests are used to narrow a problem down to one or two cylinders once a problem is already manifesting itself (engine missing, dark smoke, etc.).

Plugs are also commonly examined when removed during a plug change or removed in search of a problem cylinder in place of a compression test. An oily plug can indicate a problem exists.

During a plug change I number each old plug as I remove it, allowing me to later sit down in good light and lay them next to each other, looking for variations. Luckily my plugs (82K miles when I changed them) were all a nice light grey color around the tip with normal wear at the ground and center electrodes, no black streaks on the white insulator which would indicate flash-over from the terminal nut to the body and no rust at or just above the threads, which might indicate coolant leakage somewhere on the engine.

I agree with the SA - put the $100 towards a plug change in the near future.

Damon54
06-19-2012, 03:49 PM
My point is if I were going to do it I would surely choose one of the cylinders where known issues have been experienced in N62's. If I find one bad as a potential buyer there is little need to keep testing correct?

Of course a test on all cylinders is preferable.

An oil analysis by an independent is the path I would most recommend. Much cheaper!

bimmerfan52
06-19-2012, 07:02 PM
The impossible part to answer is what should the one cylinder read?
70lbs? 80lbs? 90lbs?

You might do one 545i on a given day with a certain set of equipment and the eight cylinders read : 91, 90, 91, 88, 90, 91, 89, 90 and you would rightly conclude that based on the deviation (lack thereof) that the leak down test was good.

A week later on another 545i with a different set of equipment you got a reading of 78lbs testing one cylinder.
Is this bad or good? You just don't know. The full eight cylinders might read
78, 81, 80, 79, 78, 80, 81, 80 in which case the 78lbs is OK.

Or the reading might be
78, 88, 89, 88, 90, 89, 88, 89 in which case the 78lbs is fairly low compared to the others.

Sampling your next door neighbor on how he is going to vote won't tell you how the other seven neighbors on your block are going to vote.

RE the Oil analysis - What if the seller changed the oil last week?

TRS550
06-19-2012, 07:33 PM
Oil changes were like clockwork every 15K and all required maintenance was kept up by the previous owners.

So in 76K miles, the car has had maybe 6 oil changes? My car has 80K on it and has had 6 oil changes since 50K.

You could not make me buy this car with a gun to my head.

Caveat Emptor.

dolfan13
06-20-2012, 05:02 AM
Rings and cylinder walls problems are very few and far between on any BMW.Seals seals seals. Don't worry about the compression test.Make sure it's not smoking or leaking like an old Pontiac.Drive it hard and use your nose.Smell smell. I pulled my engine ,replaced all the seals except head gaskets.Did valve seals heads on.Im hoping more frequent oil changes help but there's probably a design flaw in the n62 hence the n62tu.One day I am going to nail it down.Hopeful aftermarket BMW engine builders will get around to this engine and make the improvements and I'll know.Cant find 550i with all these leaks.

bimmerfan52
06-20-2012, 06:49 AM
Rings and cylinder walls problems are very few and far between on any BMW.Seals seals seals. Don't worry about the compression test.Make sure it's not smoking or leaking like an old Pontiac.Drive it hard and use your nose.Smell smell. I pulled my engine ,replaced all the seals except head gaskets.Did valve seals heads on.Im hoping more frequent oil changes help but there's probably a design flaw in the n62 hence the n62tu.One day I am going to nail it down.Hopeful aftermarket BMW engine builders will get around to this engine and make the improvements and I'll know.Cant find 550i with all these leaks.

Couldn't agree more. Oil and water gaskets!
I'm in the same boat with my 04 545i. Previous owner averaged 12K miles between oil changes and after cleanup I'm hoping that 5K oil changes will right the ship and keep it afloat.

At 75K - Leaking lower timing case cover gasket prompted dealer removal (under extended warranty) of engine and replacement of valve cover gaskets, head gaskets, upper timing cover gasket, lower timing cover gasket, upper oil pan gasket, oil pump to upper pan gasket, intake manifold gasket, valley pan cap cover, the “dreaded” water pipe, alternator bracket gasket, brake booster vacuum pump, water pump gasket, crank shaft front seal.

At 76K - Coolant reservoir and lower hose temperature sensor o-ring replaced

With pretty much all fresh seals on the top of the engine and a close eye all of the time on the coolant system I think I have beaten back the gremlins for a while.

Rule #1 - Don't let it overheat.
Rule #2 - Change the oil every 5K-6K miles
Rule #3 - Worry about rules #1 & #2

The reality is that the N62B44 engine is just a poor engine design from the standpoint of seal integrity. Great performing engine but it needs extra care to run a long time with minimal cost.

joe_capp
06-20-2012, 09:28 AM
I want to thank all of ya'll for giving me some great advice and expectations regarding the 545i motor. And I appreciate the direct candor ... taking a bullet to the head first over buying a vehicle that has only had the oil changed very 15K miles ... as it certainly gives me a great deal to think about.

Advice on this particular motor is full spectrum. Oil change every 15K miles and you will have problems, stick to the BMW schedule of 15K miles and you will avoid problems. Doesn't matter who I talk to - you good folks here who are owners (with experience) - BMW SA very respected in my area - BMW Independent Tech in my area - other online forums - I get the same advice/experience on both sides of the spectrum.

What is not in question (many of you on this thread have noted) is that while the N62 has great performance and is a blast to experience, it has its share of flaws. I may drive it for tens of thousands of miles with no leaks or other issues, but there is plenty that has to be considered on what to expect in repair bills should the flaws show up.

So at the end of the day, it's how much risk am I willing to assume and is my wallet ready to handle fixing that assumed risk. There was a time when I couldn't afford this kind of risk, but I'm older, you only live once, and I've been looking for this vehicle or quite some time - I'm ready to own it and drive it. So if all goes well with the PPI, and I will be sure to be specific to the troubled areas each of you has mentioned, I plan on being this 545i's next owner.

Of course, you folks can laugh at me :rofl: and say you told me so if I post months down the road with problems, but I'm good with that . I hope to post a picture of this beauty next week if the PPI goes well. Thanks again for all your help.

Joe

dolfan13
06-20-2012, 10:28 AM
I would be laughing at myself Joe cause I knew all this getting into it. I could have bought a reliable Japanese car(I even work for them)but....just not the same!Bimmerfan52 I agree that my car may have been over heated at some point.I had the coolant pump go out on me after first few months of ownership.My plan is to change it again at another 50k bad or not.I can do it in 2 hours or less for 250$ so why not?Oil every 5k.

WillInDenver
06-20-2012, 11:27 AM
What is not in question (many of you on this thread have noted) is that while the N62 has great performance and is a blast to experience, it has its share of flaws. I may drive it for tens of thousands of miles with no leaks or other issues, but there is plenty that has to be considered on what to expect in repair bills should the flaws show up.I own a 545 that has 74,000 miles but seems to be in great condition. I've had it since 2007 and I'm firmly on the "do the maintenance the car tells you to do" side of the conversation.

Hopefully my car won't implode over the next 20,000 miles. But it is a damned fun car to drive, still looks great, and is long since paid for. Maybe it's worth $15,000 or something close. Whatever I might want to replace it with would cost at least $50,000.

Of course it would be a travesty for me to spend $35,000 in the next 2-3 years on repairs for my eight year old car. But what if $3000 or even $5000 is more realistic? Those sound like horrible repair bills, but the economics of keeping the car would be hard to argue.