Changed Engine on my pagoda

[Shvegel]

First I apologise for the couple of false starts I had.  I blame it on Google and Dyslexia.

Trying to track down the head gasket on EPC to see if there is a different one for your head than the SE/A.  I am wondering where you engine number falls into this:

https://www.adsitco.com/parts/detail/Mercedes/head-gasket-set-130-980-to-026281-130-983-to-10-004596-to-12-007229/2156/

There may actually be 2 breaks in the engine lineup.  The early square chamber to oval then a later one?  Scroll down to application info.

https://www.ebay.com/itm/Mercedes-W108-W109-W113-280SEL-280SE-Cylinder-Head-Gasket-Set-Elring-1300103521-/350794105431

[MikeSimon]

Thank you for continuing trying to help shedding lights into my own void of knowledge, Shvegel!

The head gasket I need is the later one, the oval, not the square one. Are yo saying there are two oval ones?

My engine serial is 130.983-12-015405, so I would need gasket from engine 7230 (Automatic)

[MikeSimon]

So, after some of this discussion and input, I was afraid that someone had machined my cylinder head too far down, but then I saw this one on ebay and it looks exactly like mine as far as the combustion chamber is concerned, i.e.: without the recession around the intake valve. Although this head seems to require a square head gasket and the casting number is different.

https://www.ebay.com/itm/Mercedes-original-1-nice-cylinderhead-280SL-Pagode-W108-280SE-130-016-00-01/173007891476?hash=item284812ec14:g:53gAAOSwB3BaIDmd

[MikeSimon]

There seem to be a plethora of heads with different casting IDs out there. And there is no rhyme or reason as far as late or early heads. Most of you guys say the 280SL W113 head says "280SE/A" Mine says 280SEL/SL, and look what I found:

[Shvegel]

I think I figured it out but this will probably be too much information.  The earlier eBay head is indeed a square gasket head however notice the more open area around the exhaust valve where the spark plug is at.  Your head is much more closed in and the pocket is deeper than the eBay head. Your head would require the oval gasket.  I thought there might even be an obscure third gasket but since your serial number is within the range of the oval it doesn't matter you need the oval gasket.

 There were a bunch of head changes right around 1970.  Why?  1970 was a watershed year in terms of emission control regulation.  That was when the US and Europe  began regulating Hydrocarbon (HC) and Oxides of Nitrogen (NOX) emissions.  Hydrocarbons are not super tuff to reduce at least at 1970 regulation levels.  They simply leaned out the mixture and installed electronic ignition. NOX emissions are another bugger all together.  In order to reduce NOX you have to reduce the temperature inside the combustion chamber.  There are several ways to do this.  Retard ignition timing, reduce static cylinder pressure by reducing compression and finally add or keep a little exhaust for the next ignition cycle.  American cars basically attacked NOX with a sledehammer approach beginning with the 1971 model year. They dropped compression from 10 or 11 to one down to the 8.5 to one range and installed this neat little vacuum operated valve (EGR valve and yes I am kidding about neat) to feed exhaust into the intake manifold.  The exhaust acted like a compressible spacer so you could have less fuel and air in the combustion chamber and a lower exhaust temperature.

Mercedes did it differently because they had to.  the Americans for the most part had huge engines(Up to 7.4 litre) so the drop in power was noticable but still tolerable.  Mercedes had 2.8 litres to work with.  Here is what I see in the evolution of the cylinder heads.  the eBay head was probably the best performance casting with good flow around the exhaust valve and a small combustion chamber(high compression).  Beginning at the engine break in 1970 with the SL/A head they had to find a way to actually make the flow through the head worse so they could keep a little exhaust for the next firing of the cylinder.  They started by tightening up the combustion chamber around the exhaust valve(shrouding) this would cause the engine to breathe more poorly. then they shortened the time when both the intake and exhaust valve were open (overlap) so they could limit how much the suction in the exhaust system (Scavenging) could pull the exhaust through the engine.  At some point late in the run as your car was a Dec 1970 build they had another evolution to even more shrouding of the exhaust valve, elimination of the dished area of the chamber and a deeper chamber around the exhaust valve to lower compression.  Notice on the SL/A and your head the compression ratio casting marks have been eliminated.  They didn't want to advertise that they dropped compression.

What all that boils down to is that unlike most evolutions where things were made better each year Mercedes had to actually make there heads flow less well and they also had to drop compression as well.  Square gasket heads will not work for you.  The 280SL/A head would be a slightly better head for you but the SEL/SL head you have will work just fine.  There is a 2 or 3 digit code on the rear of the camshaft.  I am curious what it is?

[MikeSimon]

Thank you so much, Shvegel, - there can never be too much information! Your explanation is sound and probably as good as any.

I know I need the oval head gasket. I ordered one from ebay and when it came, it was the square one. When I compared it with the one I took off, I recognized it was wrong and I got probably one of the last oval ones from K&K. I am all set there.

The code on the camshaft is 02

My head does still have the compression mark, and guess what - it is 9.0. One thing I had been curious about. Your explanation would clarify that.

As far as the shape of the combustion chamber goes, I now have seen several earlier heads that do have the same look as mine. Notably the lack of a cast recession around the intake valve. Compared to the other heads that do have that, a design like that should actually have a higher compression ratio, because you compress the same displacement volume into a smaller combustion chamber. Oh, well.

Considering that the head on the car worked fine and the car was really running good before it was parked 23 years ago, I am in no hurry to change it. I would like to have a spare, though, just in case. that's why I am looking for one and am trying to find the correct one. It seems getting exactly what I have, with the same markings and same casting number will be next to impossible

[Shvegel]

Looks like it.  I just looked at my head and it shows 9.5 compression ratio.  Your head has a smaller pocket but deeper.  02 cam is the highest performance one.  I believe it matches the 09 cam but is hardened against wear.

[MikeSimon]

I am still trying to sort out the background of my "mysterious" cylinder head. It seems there was another thread a while ago where a member mentioned the same casting number that is shown on my head and some said it was a SL head, although that casting number is not listed as one in the Technical Manual.

Does anybody else have a head that has casting number  130 016 17 01 ?


https://www.sl113.org/forums/index.php?topic=4650.0

[Cole]

Hi,

I've owned all four years of 280SLs; the early ones, i.e., the '68, had a cylinder head casting number of "280", but I just saw another '68 last week with a casting number of "280 SE/A". Overall, most of the 280SLs that I've seen had a casting number of "280 SE/A" which could evidently be used on either an SE or SL motor. I've even been told that MB put these "280 SE/A" heads on SLs at the factory as these heads were compatible with either model.

Some other motor info I was given:
Differences between 280 SL and SE motors/blocks

1. the blocks are physically identical
2. SL tach drive
3. SL engine arms / motor mounts
4. may be difference in motor mounts, distributor, injection pump

[MikeSimon]

...and I am still looking for a definite answer where and when the head with SEL/SL and casting number 130 016 17 01 and 9.0 compression was used.
I don't argue that 280SE/A is a correct head for the SL and that early heads were just 280, but it looks to me that the list shown in the Technical manual is incomplete. I did not "photoshop" the picture of the my head.

[Shvegel]

Google search "280SEL/SL"

https://www.ebay-kleinanzeigen.de/s-anzeige/mercedes-280sel-sl-m130-980-pagode-w113-sl-kompletter-motor/748253180-223-8780

[MikeSimon]

The guy is selling a complete motor, which, based on his description, may have the same head as mine. Interesting thing is, he says it had auto tranny.
Maybe that was the difference??

[Peter h]

This engine runs...?
Peter

[mbzse]

.../...Differences between 280 SL and SE motors/blocks.../...

The cover over the main coolant thermostat is different. Lower design on W113, compared to sedans and coupés.
Note: the "free" lid (cover) in the second picture has a threaded fitting at its top. This was there on late 280SL (M130 engines) only.

[MikeSimon]

This engine runs...?
Peter

The seller claims it ran before it was taken out of the car.

[Shvegel]

Engine serial is 980 which is indeed a sedan.  I think there is a picture of the head casting marks.

[MikeSimon]

Engine serial is 980 which is indeed a sedan.  I think there is a picture of the head casting marks.

Good eye, Pat! It indeed shows in the picture of the FI pump 280SEL/SL. Just like mine!
If the seller was here, I would make him an offer. Wonder what he wants for it. He is asking for offers.

[Peter h]

And what kind of pump is it?
R18 pump on a 280se ?
Peter

[MikeSimon]

Peter:

Du bist in Deutschland. Du könntest den Motor kaufen in Teile zerlegen und mir den Zylinderkopf verkaufen…...

[Peter h]

My friend Roman make him an offer.
He is waiting for an answer.
You need only this head?
Monday we went to Florida. But I thing it's to big. 
You must speak with Roman, maybe he can find this kind of head here in Germany.

Peter

[MikeSimon]

Who is Roman?
I would take the complete head without the camshaft.
Cam holders, valves, rocker arms, ball studs included.

[Shvegel]

I would take the cam etc if it is stamped “02” on the end.