Hi all,

I bought an e55 amg s211 a few months back. Recently it started a dreadful knocking sound. I removed the valve covers in hoping for a valve failure or something. After boroscoping the cylinders i found the culprit. 1 piston in the cylinder had a hole, i think it was detonation due to a bad tune.

So my question is, what is the root cause of this problem. The engine was running strong, and the remaining internal parts is suprisingly clean. And what is the best solution, rebuild, buy an engine block and swap over parts, or an entire new engine?

Background info about mods engine wise: Long tube headers, x pipe. 77 mm pulley. Belt wrap kit. And a retune.

Photos:

The fauly piston/cylinder

The faulty piston/cylinder

 

Cheapest....find a used engine.
Expencive ...rebuild it and that will take ALOT more time and effort.
You can piece it together by swapping over to a good block and pistons but again more time and money and you better know what your doing because it will be some work.
Also you may have a bad injector on that hole so check them all out for sure.

 

I will check the injectors, do you think it may have stuck open or pushed in too much fuel? And i'll do most of the work my self. i will only let the machine shop hone and sleeve or such the cylinders if i choose to repair the block. I live in sweden and there is no engines here, and if thefe are any they are so expensive.

 

Your looking at around 5-6 thousand for sleeves and pistons so be ready for that hit !!

 

sorry to see that you have this issue man

if this is cylinder 4 or 8 then it is common for those cylinders to go bad due to fuel starvation ,,,as @SICAMG said inspect the injectors for those two.. and cylinder 4 and 8 is the back cylinders the last ones ... closest to the fire wall

77mm pulley on the stock injectors is not maxing the duty cycle of the injectors so it is a low probability that duty cycle could do this but since the car is old you may have a bad injector or a bad tune ...

if your bore is ok then you can rebuilt it but the trick is that u will only know that once you remove the cylinder head to inspect and measure the bore

 

my openion is get a used engine and use this one for the future parts ... will be less cost on the short and long run ... but also change your injectors on the new to you used engine and install the 550cc or the 630cc bosch injectors with a tune and you will be good to go

also double check your fuel pump flow to make sure it is not the cause of the issue . to do that you need to connect a pressure gauge to the fuel rail end while the car is running on idle to see what pressure you get .. the car should be running for awhile to make sure that the fule pump is already hot and stressed ... these cars produce 83psi of fuel pressure on idle

 

Thanks for the insight. Does this bore look repairable? I've read that alusil may be bored with a special paste. If it's to deep then the alternative is sleeving i suppose? The cost of an entire engine is absurd in sweden, we are talking 6-8 k if there are any ofcourse. I will start taking the engine out of the car, what is the easiest method? Taking front apart and pulling engine with subframe and gearbox. Or taking the engine out with a crane?

 

i cant tell much from the picture but here is the principles :

if the scratches is not deed then polishing will fix the issue and you have nothing to worry about
if the scratches are not so deep then you can increase the size of the bore ( very minimal ) to remove the scratches and get away with it but the down side to it is that you will burn more oil and your compression might be little lower then normal
if the bore is oval ( which happens only in the case of excessive over heating ) which i DONT think it is your case then install new sleeves is the only option

as i said before , the best option is getting a used engine ... but adding the fact you mentioned about the price tag for it in Sweden, i would just remove the engine and inspect , if you got scenario one ( small scratches ) then respond to it ... if you got scenario two , then i would install new sleeves and be done with it .... if god forbid you got scenario three then you know you have choice of getting new engine... at least if it came to it you know that you did your best to save some money but it is the only solution .... well unless you are considering selling the car without engine... but to be honest i think scenario 2 is more likely ....

 

It always depends on where you stand with the car. When mine cracked a piston my thought process was, I not going to another platform to start all over, the car is very rare with some great history and I have no intention of ever selling it so screw it....spend what ever it takes to get it fixed !!
My wife even agreed with this thought process even when I said maybe I should sell it but, what could I get with a broken engine anyway ??

 

I will start tearing it apart this weekend, how do i know if the scratches are to deep, what is max and minimum diameter for the cylinders? I bought the car to keep it so selling is not an option, i wan't to rebuild it so that it lasts and ofcourse the most budget friendly way

 

I agree, i bought mine with the intention to keep it for a long time. What happened to your engine, was it a similar case as mine?

 

No. A little to much Nitrous and she split a piston in half. Block was perfect but I sleeved it any way for more power in the future

 

What sleeves did you use. Did u have to change something else, like pistons etc. What brand did you go for and how much did it cost you?

 

Dan Benson Racing did the sleeve job. It's now $4,000.00 to do the block where I paid $2,400.00 three years ago !!
Pistons are $2,500.00

You are better off fixing the block " re-hone it " and just replacing the factory pistons with used one's to save money.....unless you want to get crazy with it then spend the money.

 

Pull engine from the top and leave trans in, these are very easy engines to pull from these cars. Leave everything on the block except the AC pump so you don't have to recharge the system.

 

Hmm, i have a garage but not a lift. Don't you think it will be hard to undo the trans from the engine without a lift? Do you have a solid link/tutorial that you can suggest for removing engine without a lift?

 

Just jack the car up high, remove bell housing bolts and torque converter bolts from flex plate.First exhaust comes off to make it easyer.

 

I do it with no lift ALL THE TIME !

 

I am in the process now. Do i undo the trans bolts from underneat, any tricks? And what do i do with the ac lines?? Everything else is sorted fingers crossed, i bought an engine lift.

 

Yes all the bolts you can reach. You can also get the very top ones from the top of the engine if you do not have a long extension. I prefer this since I have done it so many times.
6 flex plate bolts.
Engine mounts.
Exhaust H - pipe...Do this first.
I leave the wire harness still on the engine and just unplug everything from the drivers side box/computer.
Connect a chain to the two rear engine lift brackets and the two holes on the front of the supercharger.
Engine will lift straight out.

Make sure you have a jack under the trans of course.
The AC pump gets unbolted and just pushed aside, the lines will stay.

There is a few other things,bolts,brackets to remove of course and you will see them as you go along but I leave as much on the engine so when it goes back in I am spending a lot less time bending over the car during reasembly.

 

Simple and clear instructions, thank you. I will update whether i succed or not

 

Nuts and bolts.....that's all it is !!LOL

 

Happy to say that the engine is out, it was a lot of brackets and lines but managable thanks for all the help. So next step will be teardown and inspect. Anything special i should think about before i start ripping it apart? I know that there are a lot of one time use bolts and so on.

 

I'm proud of you man, good job !!!!

1 -Remove the Crank Damper. I should have told you to do that first before pulling engine because its on there real tight but it's doable. Keep things clean and organized .
2 - Pull the blower off. Keep things clean and organized.
3 Loosen the chain tensioner ...right behind/next to the alternator.

3- The cylinder heads come off in a particular bolt pattern. Pull rocker arms, throw bolts away they are one time only. When taking rockers of Loosen the bolts from the center out. Don't just remove the bolts all at one time....loosen them systematically until they are all completely loose and then remove them.....this is important. The girdle is under a lot of stress from the lifters pumped up and will be "pushing" real hard against the valves.
Throw head bolts away one time use as well and replacement head stands will be much cheaper than factory bolts. Keep things clean and organized.
Front to back....
1 5 9 8 4
2 6 10 7 3


Then the oil pan, pump and second oil pan. Keep things clean and organized.

Then front cover. Try and keep track of where the bolts go as most are a different size. Get a big piece of card board,trace out the cover with all the bolts and just stick them through a hole in the card board that matches up with your drawing. No brainier putting them back in.

We will stop here until pistons come out.

Keep things clean and organized. I may have said this one other time LOL

ANY TIME you turn the engine over ALWAYS turn CLOCKWISE...ALWAYS especially when assembling.If you don't the chain tensioner will unload on the chain meaning take all the slack out.

This how I do things and it will not fail you.
Others can chime in and say it's not needed this way of doing things so do what you feel is best.

 

One other VERY important item. The timing IDLER gear in the center of the block is a REVERSE THREAD. Remove it turning clock wise....if you take it off. Most often not needed to remove unless doing block work.
You will snap the bolt going the wrong way and will be very pissed off.