Author Topic: What to do at the same time as the head gasket?  (Read 4317 times)

col320ce

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What to do at the same time as the head gasket?
« on: June 21, 2016, 13:08:55 »
So my 230SL (1964 manual) needs a head gasket change. The engine was fully rebuilt about 10 years ago and has only done about 5000km since and its a very low mileage car (50,000ml).  The alternator is not working either.  So ... is there anything else that is recommended to do at the same time?
Col

1964 230SL
1965 250SE coupe
1993 320CE Sportline

Shvegel

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Re: What to do at the same time as the head gasket?
« Reply #1 on: June 21, 2016, 14:07:10 »
Water pump, coolant hoses and replace valve stem seals.

stickandrudderman

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Re: What to do at the same time as the head gasket?
« Reply #2 on: June 21, 2016, 15:18:09 »
It really depends on how you define "engine rebuild".
If it didn't have valve guides then it should certainly have them now.

col320ce

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Re: What to do at the same time as the head gasket?
« Reply #3 on: June 23, 2016, 12:57:31 »
The rebuild was pretty extensive and I can see the valve guides on the bill so that's taken care of. I have no evidence that the water pump has been done so I'll do that. The alternator is not working so I'll do that too.

The BBB covers the 190 and 220 diesel engines ... I can't find specific instructions for the petrol engines.  It looks pretty straight forward to follow my nose but am I missing something in the BBB?

Thanks again for any help ...
Col

1964 230SL
1965 250SE coupe
1993 320CE Sportline

Cees Klumper

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Re: What to do at the same time as the head gasket?
« Reply #4 on: June 23, 2016, 15:04:33 »
Do you know why the head gasket failed? You want to make sure you address the root cause of that. The Haynes manual for our cars covers the engine teardown and rebuild process, and I'm sure there's lots of info in our tech manual. And of course the Mercedes shop manual, aka the Big Blue Book.
Cees Klumper
1969 Mercedes 280 SL automatic
1968 Ford Mustang 302 V8
1961 Alfa Romeo Giulietta Sprint Coupe 1600
1962 FIAT 1500S OSCA convertible
1972 Lancia Fulvia Coupe 1.3
1983 Porsche 944 2.5
1990 Ford Bronco II

Tyler S

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Re: What to do at the same time as the head gasket?
« Reply #5 on: June 23, 2016, 15:19:20 »
As Cees mentioned the BBB, you need the torque sequence and specs. Its in there, will find you a page # in a bit if no one beats me to it. You should probably replace the head bolts as well. They do stretch. Also check the head for warpage. Anything over .003 you should send it out to be straightened/milled. Verify the thickness before hand to make sure it is serviceable. A new or untouched head is roughly 85mm thick. A max of 1mm total top and bottom can safely be milled from it. Find a shop that can heat straighten it before milling to preserve as much material as possible.
1968 (67) 250sl. 4 speed manual. DB180 Silver
1955 220 Cabriolet A. White Grey
2019 E450 Wagon. Majestic Blue
1936 Ford PU Flathead V8. Creme on tan interior.
1989 Volkswagen T3 Westfailia Campmobile. Dove Grey (blue)

col320ce

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Re: What to do at the same time as the head gasket?
« Reply #6 on: July 02, 2016, 11:01:56 »
It's warped like a banana so getting it heat straightened. So much so that the cam is hard to turn. Needs some welding.  and if you've seen my other post re the voltage regular you'll have already found out that the engine dude said he thought at least some of the damage was from electrolysis... I think it also looks like the engine got too hot at some point. I'm replacing the head bolts, water pump, thermostat,  voltage regulator, and all the relevant seals/gaskets/washers. The valve guides are good but might need replacing as the head is borderline soft and may need hardening. Waiting for a hardness test.
Thanks again...
Col

1964 230SL
1965 250SE coupe
1993 320CE Sportline