220 head - PeachParts Mercedes-Benz Forum

spencerbandit88 · #1 07-30-2004, 01:14 AM

Hello,

I have a 72 Mercedes 220/8. It's a 4 cyl with a sohc. How do I get the head off of it. There is the timing chain at the front and I don't really know what to do with it, how to get it off, how to make the timing stay correct. I don't really know how to adjust the timing, so I don't want to cause it to get changed.

I just want to look at the piston rings and see what condition the engine is in. This is the first time that I have pulled the head off of an engine, so I don't know what to really expect from it all. I was hoping that there might be a piston ring that is sticking to the piston and not making a good seal, would I be able to see at least one piston ring.

Thank you

spencerbandit88

cth350 · #2 07-30-2004, 07:41 AM

No, you won't see a piston ring unless you also remove a piston. You will be able to see the walls of the cylinders and get an idea if they're scraped up.

Pulling the head isn't particularly difficult. It takes a few hours if you have the right tools. It also helps to have a bit of common sense and patience. Prior experience isn't necessary. Though it always helps.

Assembly time is more difficult than disassembly for several reasons, including, getting the timing right and putting everything back where it came from (there are dozens of interlocking parts) and getting the assembly tolerances correct.

Having said all that, what is the problem you're trying to solve? Pulling the head off just to see what's under it is a lot of work to convince a ring to not stick. Also if it is a sticky ring and you want replace it, you have to remove the engine from the car, and after removing the head, remove the pan and the crank too.

Explain the problem and we should be able to help you diagnose the cause and suggest a cure. BTW, a cost-effective solution to a screwed up engine is to get a used one and drop it in.

-CTH

spencerbandit88 · #3 07-30-2004, 02:25 PM

Well I don't really know how to get the cam off. So I can even see the top piston ring with the head off?

And I cant find an engine that I want to buy and put in and also I don't have the tools to change the engine. Someone offered me a Mercedes straight 6 engine that ran and will fit in the place of my 4 cylinder, but he wanted $600.

Thank you

specnerbandit88

cth350 · #4 07-31-2004, 10:29 AM

Removing the whole engine requires one specialized tool, an engine hoist. A complete set of metric wrenches & sockets, screw drivers, a jack & jackstands is all it takes. That and a several hours.

Replace the engine with another 4 cylinder or you'll have all sorts of conversion problems that you're not ready to deal with. An engine with a guarentee should set you back about 500$, plus shipping.

You still have explained why you think any of this is necessary. Engine problems can, in certain circumstances, be minimized by changing the oil and driving the car (mercedes don't like to just sit there and rot). Then again, they could mean the motor is outright a gonner.

-CTH

skalie · #5 07-31-2004, 04:31 PM

Compression test?

spencerbandit88 · #6 07-31-2004, 04:51 PM

I have done a compression test. There is a thread some where with the results.

Well i'm not going to get a new engine, it's on it's second engine. There should be a 115 and there isn't, on a 115 the valves are all in a row, the ones on this engine are not.

If there is a stuck ring then, how can I free it up. Someone told me solvent will work, just put some into the cylinder and turn the engine by hand, it is true?

spencerbandit88

skalie · #7 07-31-2004, 05:12 PM

Coca Cola

spencerbandit88 · #8 08-01-2004, 12:50 AM

Quote:

Originally posted by skalie
Coca Cola

Umm...

I know coca cola (not pepsi) is a good emergency brake fluid, but no other.

skalie · #9 08-01-2004, 02:46 AM

Know a guy who unseized a tractor using Coca Cola, he took out the injectors, poured it in and waited over night.

Something to do with the "You can dissolve a nail in a glass of Coca Cola" theory.

Could be an urban myth of course.

spencerbandit88 · #10 08-01-2004, 03:05 AM

Hmm.... sounds like crap to me. NO OFFENCE TO ANYONE

But i think that the solvent sounds better. But coke cola will clean a penny. Mythbusters on Discovery Chanel.

But anything is worth a try. Maybe i'll go get an old lawn mower and try it with that.

spencerbandit88

#11 08-01-2004, 09:42 AM

Use kerosene, rislone, or mineral spirits. All are similar things that will clean up the gunk, and hopefully free the rings.
Thanks
Tim

spencerbandit88 · #12 08-01-2004, 02:30 PM

Hmm.... I think I'll try that. Then the coke.

thanks

spencerbandit88

wbain5280 · #13 08-03-2004, 12:15 AM

Try a leak down test. The cylinder is pressurized with an air compressor and they you listen for leaks.

BTW, getting the head off is not that difficult. You will need a gasket set.

HGV · #14 08-09-2004, 02:44 PM

My father in-law serviced P-38's during WWII and he would take the plane and run it up to temp and then start sprayiin Marvelous Mystery Oil into the intake, and when the exhaust started to run dark, he would shut the engine off and let it sit over night. He would then go out it the morning and start the engine and run it up to speed and blow it out. He said it would clean up stuck rings and valves and give the plane another lease on life. I have done this on my cars and it made a differenece and never did any damage.

I am confused bythis post though. Give the results on the compression test and get the engine model. I am confused by your reference to the valves not being in a row.

I would not take the head off unless you have abeeter idea of what is wrong. If you have a stuck ring, youwill need to pull the engine and remove the pistons. Removing the head won't tell youmuch.

Henry

spencerbandit88 · #15 08-09-2004, 03:16 PM

Is what I meant by the valves not being lined up they are diagonal from each other.

/
\
/
\

kind of like that. With the exhaust on the right and the intake on the left.
But in the manual I have it show the valves in a line or row not diagonal.
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