Changing piston rings M110

Hi all.
Three years ago the head gasket failed on my 280SL.
Water leaked into cylinder 6 and the car was not running proparly. As the car had been smoking quite badly during deacceleration I also changed the valve stem seals and lapped in the valves.

Year or so after, the car started started smoking again.
Now it is so bad that it is quite embarassing to drive downhill during daytime.

I checked the compression in the cylinders and they were relatively equal , but compression increased with a couple of teaspoons of oil in the cylinder.




I decided the piston rings need renewal.
As the engine mounts are virtually impossible to access I decided to remove the head first. I had done this before and had the tool for it.


The passenger side mount is under the manifold. The other is more difficult to reach



Now I have loosened all the bolts on the head but it is impossible to lift. I took out the 14 big and the 3 M8 bolts but still it is stuck.
I can not reach a good place to get a chisel in or anything to pry it of without fear of breaking anything.

So, if i need to get the motor out in one piece, does anyone know of a good way to get to the motormount bolts?

Aloha Uncle Benz,

I guess the M110 has 4 M8 Bolts in the Front of the Cylinderhead. 3 Inside, 1 outside.

Hello Uncle Benz!

Access to the motormount bolts is given from underneath the car , through the front axle subframe.

You will find a hole on each side of the the frontaxle subframe between the front and rear subframe mount. Through that hole you must insert a long hexkey (allenkey), to reach up into the head of the hexkey bolt.

The motormount bolts go through the motormount into a weld-on nut on the motor dampener bracket ( shown on your last picture, just underneath the exhaust header).

I welded the hexkey into a socket (1/4 inch drive ) that reaches all the way up . Total length of the tool should be about 5 inches.

Regards,

Joe

2 bolts inside, one outside.
These are all I can find.
Also according to this site # 22 there should be two inside
mbci.mackuz.ovh/index.php/warsztat-mainm...ion-of-cylinder-head

The Cam-housing is removed? If not, then loosen the 1. Front M8 Bolt on the LEFT row (intakte side) of Bolts for the Cam-housing.

Richard had it not been for Covid I would have come down and handed you a beer!

A beer is welcome
Good luck for the further workshop jobs.

PS: What is your first name? Usually we talk and sign to each other with our first name.

Got the top off, and got the engine out.


BUT, cylinder 6 has som serious scaring.







Best regards
Stian

Hello,

the "scoring" will be most likely alloy from piston top land.
You can clean the liner with a steel brush on a grinder or with caustic soda. It will clean the liner surface and the "scoring marks" will disappear.

Possibly this was the cylinder with the damaged head gasket and water entered the chamber and caused the damage.

Most likely not serious and can be reworked if the piston is ok.

Do you got access to a machine shop/ engine builder?
Just asking because your liners should be treated/ honed before your start with fresh piston rings.


Kind regards


JP

Hi JP.
I think you are correct. Most of this is deposits can be cleaned and honed out, but there is some pitting in there also.

However. An acquaintance was in the process of clearing out his store of used Mercedes parts as his interests had changed and rent was going up.
He had several M110. So I rescued one.





This came out of a W123 roughly 10-15 years ago. I'm planning on using the intake manifold from my engine and changing all that is needed to fit it into my car. Then I can drive this for a few years and see if I want to dig deeper into the original engine. As per now I need to get it done and move over to more domestic tasks.
The WAF (wife acceptance factor) is pretty low at the time, as I just spent a year and a ton of cash on my 300SEL. On top of that it has spent 6 months at the gearbox reapair shop waiting for a complaint on repairs.

Stian

This engine came with a gearbox, and as mine have a leak I had hoped to change this also.
Mine has had an impact on the side and has been glued.



This happened dureing transport when i replaced it i approx 2006,
So the glue held until now.
As the new box is from a 123 it has a speedowire, not the sensor as the 107.
Would this be easy to change? Anyone know?

107


123



Mvh
Stian