Pagoda SL Group

W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: CJHenderson on August 19, 2020, 13:49:05

Title: Rework aluminum head
Post by: CJHenderson on August 19, 2020, 13:49:05
I live here in central Arkansas and need to find a place to get the aluminum head reworked. Have called around but no one knows of anywhere that will do it. Does anyone know who can do it that is in reasonable distance?
Title: Re: Rework aluminum head
Post by: Benz Dr. on August 19, 2020, 16:29:25
Distance should be of less concern than proficiency.
Title: Re: Rework aluminum head
Post by: CJHenderson on August 19, 2020, 16:39:40
That's true and am getting to the point that I will be taking it apart and do the refurbish. The main issue is to polish the face, the only way that it can be done is lay emery cloth on a level surface and move the head back and forth across until i can lay a straight edge on it and not see light.
Title: Re: Rework aluminum head
Post by: mdsalemi on August 21, 2020, 15:42:17
Why is it necessary for Central Arkansas? Do you want to watch them or something?

If this is NOT something you have done before, and you were prepared to send it out, why don't you send it to a specialist?

Personally, I'd send mine to Mike Elias at Metric Motors in California. But, there are a number of other specialists out there such as Bud's, SL-Tech, and others that probably do not do the work in house but do have a local person to THEM on tap for such repairs.

If you want to do the work yourself, you might consider contacting Pete Lange in Seattle ("theengineer" on the forums) I remember he did some work on his head because it had been decked improperly, maybe he can guide you.
Title: Re: Rework aluminum head
Post by: CJHenderson on August 24, 2020, 00:06:56
Thank you for that information and it may just come down to that, right now though I think that the surface may do for the time being. The black stains on the milled surface seems to be from the previous owner only ran water without antifreeze.
Title: Re: Rework aluminum head
Post by: Benz Dr. on August 24, 2020, 02:40:23
That's true and am getting to the point that I will be taking it apart and do the refurbish. The main issue is to polish the face, the only way that it can be done is lay emery cloth on a level surface and move the head back and forth across until I can lay a straight edge on it and not see light.

I don't see any cavitation from running straight water so you're lucky on that one. I'd measure the thickness of the head which should not be less than 84.00 mm or it's junk. If you just want to clean the surface to see if it's reasonably straight that method may work but I sure wouldn't count on it to be as straight as planing at a machine shop. What about the top of the head? Is it level and in-plane with your bottom parting surface?
Why are the combustion chambers so wet? Looks like it was blowing a serious amount of oil. That head will need valve guides and that'snot a DIY job.
Title: Re: Rework aluminum head
Post by: merrill on August 24, 2020, 13:45:29
metric motors in california is the recommended shop that most restorers use
Title: Re: Rework aluminum head
Post by: CJHenderson on August 24, 2020, 15:31:44
Awesome thanks
Title: Re: Rework aluminum head
Post by: Cees Klumper on August 24, 2020, 21:44:50
Noel's in Florida also has had a good reputation for rebuilding Mercedes engines:

https://www.noels.com/
Title: Re: Rework aluminum head
Post by: CJHenderson on August 25, 2020, 00:01:20
Thanks all for the great inputs. Called Metric today and they are fantastic. Mike the gentlemen that I talked to explained to me how to check if my head is within limits. I checked it and found out that it is in limits but barely, it cannot be shaved again by my measurement. They don't sell just the head unless it comes attached with a long block which will cost $9100.00 plus. So with that in mind I'm going to reassemble the motor and see how it works since I have all of the parts from SLS in Germany to allow me to do that. The car has only 102,000 miles. If it doesn't work out then I'll get one from Metric. Once again thanks for all of your advice.
Title: Re: Rework aluminum head
Post by: MikeSimon on August 25, 2020, 12:08:13
I was always wondering what exactly all the implications are of a head that is just below the minimum of 84mm. I can see valve to piston clearance, camshaft height, etc. Maybe someone can list all the areas of concern
Title: Re: Rework aluminum head
Post by: CJHenderson on August 25, 2020, 13:35:35
Here is a link that I think will help answer your question.

https://www.enginebuildermag.com/2014/10/head-surfacing-straightening/
Title: Re: Rework aluminum head
Post by: mdsalemi on August 25, 2020, 21:46:06
...Called Metric today and they are fantastic...They don't sell just the head unless it comes attached with a long block...if it doesn't work out then I'll get one from Metric. Once again thanks for all of your advice.

Yes, Mike Elias is great. If you do ONE thing for a very long time (in his case, build/rebuild Mercedes-Benz engines) you do it exceedingly well.

You might consider, CJ, to start looking for a cylinder head. They are not on the shelf at AutoZone, of course, and Amazon won't deliver one, but put the feelers out, scour the internet, eBay, Craigslist, etc. and one will pop up. Maybe not today, but possibly tomorrow...or next month or next year. In that case get the head, and you'll have one on hand for when you really need it. With these old cars, you have to follow the old mantra of "drink before you're thirsty and eat before you're hungry"; translated here, buy the head before you'll need it since you know yours is at the limits.  Good luck!
Title: Re: Rework aluminum head
Post by: mdsalemi on August 25, 2020, 21:51:55
Noel's in Florida also has had a good reputation for rebuilding Mercedes engines:

https://www.noels.com/

Someone told me a few years ago, they had shut down. Perhaps not?
Title: Re: Rework aluminum head
Post by: MikeSimon on August 25, 2020, 22:34:22
Here is a link that I think will help answer your question.

https://www.enginebuildermag.com/2014/10/head-surfacing-straightening/

It doesn't really. The only issues they think you have is "weakening the casting" and "increasing compression"

Neither one would be a concern in the specific case of a Pagoda head, that is, let's say, 83.8 mm.

BTW, I have a spare late 280SL head that I do not need.