New here with broken car.

[Ken_R]

Just mark the big end halves so that they go back together in the same orientation.

Paint pens from Screwfix are good for that.

 

[LostKiwi]

That isn't a lot of damage?

 

[Diddles]

They look different to mine.

 

[alexanderfoti]

Hoover up with the pistons at TDC, best way to get the crud out of the gap between the piston and rings.

That isn't a lot of damage?

They are aftermarket, these are standard:

There is a very small piece missing.

 

[Diddles]

All that metal in the bores they must be scored. Really worse case scenario has happened, so disapointed.

 

[alexanderfoti]

All that metal in the bores they must be scored. Really worse case scenario has happened, so disapointed. View attachment 42514

The bores don't look scored, clean the coolant off and take a better picture. Looks ok to me?

 

[LostKiwi]

Looks ok to me too (and well spotted on the aftermarket).
I don't think things are as bad as you think.

 

[Diddles]

I'll have a look again tomorow as the car is at my parents. So ill have another look tomorow. Never changed pistons so would be a new experience.

 

[alexanderfoti]

I'll have a look again tomorow as the car is at my parents. So ill have another look tomorow. Never changed pistons so would be a new experience.

First time for everything!

 

[LostKiwi]

The only thing that would slightly concern me is this:


Try cleaning off the tops of the pistons with a rotary wire brush.
Put the piston at the top of the bore, then gently run the rotary wire brush over the surface of the piston to remove the carbon. This will make the piston surface irregularities more obvious.
Wipe out the bores with paper towels. Turn the engine over by hand several times stopping at half way down the bore to wipe the top of the bore, then continuing to past top centre and repeat. After a couple of turns most of the crud in the bores will be left at the top and have been cleaned away.

 

[Diddles]

Yep where has that bit gone.

 

[LostKiwi]

Yep where has that bit gone.

Probably out the exhaust valve.

Check the exhaust manifold and turbo exhaust turbine.

 

[Diddles]

It's a kompressor so no turbo? I'll have closer look tomorow and clean the bores up to see if its even salvageable. Piston 4 looks to be cracked in the same place but will double check tomorow and see if I want to go any further with it.

 

[LostKiwi]

It's a kompressor so no turbo? I'll have closer look tomorow and clean the bores up to see if its even salvageable. Piston 4 looks to be cracked in the same place but will double check tomorow and see if I want to go any further with it.

Of course it is (duh!). Even better then. If it had a turbo the piece could lunch the turbo vanes. As it is drop the cat out and up end it. The piece will glow hot in the cat and eventually cause it to fail.
To change pistons is pretty trivial - really just the cost of parts and some extra work removing sump, big end caps and giving the bores a light hone.

 

[Diddles]

Yeah almost sounds like buying a second hand engine and replacing the sprockets and chain would be an easier option.

 

[Diddles]

Anyone know of a reputable place to buy a 2nd hand engine?

 

[John Laidlaw]

Hmm.. is it worth it?
Not sure you’d get value back

 

[alexanderfoti]

I would cross ref the pn and buy a second hand piston or two on ebay:

https://www.ebay.co.uk/itm/MERCEDES...149053?hash=item1ec51ecd3d:g:5nsAAOSwU8hY7NeF

If the car is in good condition, what is another 50/100 on pistons?

If not, then I don't think removing the engine/replacing is worth it.

 

[LostKiwi]

Have you cleaned off the pistons yet?
Get us photos if the worst damage as so far I've seen little reason not to put it back together.

 

[Diddles]

Well the car has cost me nothing yet and is immaculate. A second hand engine is around £800 on ebay then plus m271.com chain kit and adjusters would make it £1200.

No I'm cleaning them tonight and will have a look at the bores and inspect the other pistons.

The subfrsme has to come down to remove the sump and my parents drive is on a slope so pretty hard to do. I think if i was going to replace the pistons I would remove the engine.