S62 Engine Failure? Comments Please...

sonnyroy · 29th June 2008, 00:48

Hi all, just buy a M5 last week with engine problem, the engine had a strange sound like a rod sound but that was not. I took of the engine and tale off the oil pan. There was no trace of copper in but the bottom of the oil pan was cover of dark grey stuff. The sound was from the rear of the engine so I start to remove the rod cap on the number 4 and 8 and there no trace of wear on the bearing, then I was confuse because I try to find that sound since a wile... Conclusion, there couple of cylinder with gripped pistons. lot of aluminum stick on the cylinder. Am quite confuse about that. These 2 cylinder, the spark plug was really cloged of carbon. Look like the carbon damage the cylinder. Now the engine block is damage, solution is to put a new block but here in Canada, the M5 is quite rare so the spare engine is really hard to find... The problem is to rebuild the block... When I was younger I had some dirt byke and of course I blown some engine, that was the same story about the Nikasil coating on the cylinder but there a company near to my house who are specialist for recoat the cylinder with nikasil where I use to send my cylinder before for recoating. I will call monday to check how cost for recoating all the cylinder. The S62 engine is Alusil coating, basically kind of hardened aluminum but soon you start to grip, it's easy to wear the cylinder more fastest, the Nicasil is way more harder so if they can do it, I will send my block for get a Nicasil coating. The other option is to install new sleves but by personal experience with sport compact engine with sleve installation, that was bad so I will prefer to recoat... I have no idea how many people live this experience but that not funny and expensive. I will verify this option and if it's possible to recoat the block I guess lot of people will go for that better to buy a 7000$ empty block

. If you have any better idea, please feal free and comments.

ard · 29th June 2008, 03:12

Dark grey stuff might be your bearings.

Look, this engine sounds trashed... unless you KNOW the crank, rods, camshafts etc are good (perfect, optically no marks) you may be chasing a loosing battle.

I can NOT recall a single successful 'recoating' of a cylinder. One member had a light honing of a cylinder, which was likely an experiment by BMW just to avoid an expensive new motor. There have been one or two sleeved motors.

At the end of the day, you will spend close to the cost of a used motor- any money you 'save' will likely be due to trade offs you make in the rebuild/inspection, which will increase the risk of future problems.

Why did you buy this? Very cheap?

A

sonnyroy · 29th June 2008, 03:18

Well, everithing is fine, just the cylinder and pistons are damage, for get a used engine, am not in california here, I saw 2 M5 in my life here, the first about 5 years ago and the second...mine. I had very very bad experiences with darton sleeve in honda engines before so I don't reallt want to risk to broke this block. I will call tomorrow for the coating then will give me a better idea. Am just worry about the pistons, I don't really want to pay the price at the dealer...

rdm190 · 29th June 2008, 03:43

I think what Ard was trying to say is if there is already that much damage to the engine and you do not have a defined cause, you may be in for massive headaches.

If you recoat and have a bad rod bearing or a bad crank bearing then you are going to toast all you efforts in a matter of seconds. If you crank is scored, valves are damaged...etc...

If you cannot, 100% pin point the cause of the problem. I WOULD NOT start throwing parts and ad hoc repairs at the S62. It has proven to be cost inaffective.

Getting a used motor has proven to be much more cost effective in all cases I have seen.

sonnyroy · 29th June 2008, 04:04

Am really confuse because, when I took off the valve cover first, there is no sign of oil smoke stick on the metal, also the oil pan after removed, also no sign of oil smoke stick on the steel, All the bearing look brand new with no scratches. Seem that engine been open before and been rebuild...I will try to trace back the story because the cylinder look very scratched. I saw actually many pictures on the board of many engine open and all their interior are cover of oil smoke and they have less milleage...I don't know how to spell that in english abiout the oil smoke but more the engine take oil or get wear, the oil color stick on the steel...

rdm190 · 29th June 2008, 04:16

Quote:

Originally Posted by sonnyroy

Am really confuse because, when I took off the valve cover first, there is no sign of oil smoke stick on the metal, also the oil pan after removed, also no sign of oil smoke stick on the steel, All the bearing look brand new with no scratches. Seem that engine been open before and been rebuild...I will try to trace back the story because the cylinder look very scratched. I saw actually many pictures on the board of many engine open and all their interior are cover of oil smoke and they have less milleage...I don't know how to spell that in english abiout the oil smoke but more the engine take oil or get wear, the oil color stick on the steel...

I understand your fustration, but as you stated above "I am really confused". I would not make any repair decisions until you know what the issues are with this engine. Do a leakdown, compression test..that will give you a good starting point. I am concerned that you say the engine has a knocking sound. A scratched/scored wall should not produce this sound. If the wall is badly damaged it should show in a compression test.

On a side note: You do know that the S62 will have a slight "diseling" noise to its valve train ona perfectly healthy engine.

rneedham1979 · 29th June 2008, 04:19

Pics?

sonnyroy · 29th June 2008, 04:26

Sorry, not today, I will finish to open the engine tomorrow and I will take more picture. As all german cars, you need special tool as torx but long one for the flywheel...

This is more complex that any other engine that I seen, need lot of room to disasembly this guys...Will let you know...

ard · 29th June 2008, 06:28

Quote:

Originally Posted by sonnyroy

Am really confuse because, when I took off the valve cover first, there is no sign of oil smoke stick on the metal, also the oil pan after removed, also no sign of oil smoke stick on the steel, All the bearing look brand new with no scratches. Seem that engine been open before and been rebuild...I will try to trace back the story because the cylinder look very scratched. I saw actually many pictures on the board of many engine open and all their interior are cover of oil smoke and they have less milleage...I don't know how to spell that in english abiout the oil smoke but more the engine take oil or get wear, the oil color stick on the steel...

Do you mean 'varnish'? that light brown color within the engine? Not often with decent maintenance and synthetics

You say the engine was taken apart? HUGE, HUGE, HUGE red flag

Take the VIN to a BMW dealer and see if they can tell you what work has been done- not who owned it, just want kind of warranty claims there have been.

If it is true that someone else did a repair on this engine, look at the result! I am sure that you think you can do a better job- and hey, maybe you can- we don't know who you are.... BUT, there are not many people in the world who can do what you are thinking you will do (success is measured in another 100k miles, not till you sell it.) If the engine was opened you have nothing but a box of parts. Your could have other parts damaged, but no sign of abnormal wear yet, who knows....

Keep us posted. Should be interesting...

A

MarkQC · 29th June 2008, 08:12

Quote:

Originally Posted by rdm190

........Do a leakdown, compression test..that will give you a good starting point. ..........

+1