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This section describes major components of the engines and the engine variants of the Mercedes-Benz 230SL, 250SL, and 280SL, of buildseries W113.


The engine (or Motor in German) powers the car. The following document is a 12 page specification of 6-cylinder Mercedes Benz engines from 1962 - 1972.


M127 Engine


Index to Cut-away Engine:

1. Vacuum Cell11. Valve Cover21. Rocker Arm31. Main Bearing Cap41. Flywheel Housing
2. Distributor Cap Cover12. H T Lead Resistor22. Ball Stud32. Starter Motor42. Crankshaft
3. Distributor13. Cold Start Valve23. High Tension Lead33. Cylinder Block43. Connecting Rod
4. Duplex Timing Chain14. Distributor Vacuum Line24. Hot Water Pod34. Inlet Manifold44. Oil Sump
5. Oil Filler Cap15. Water Line To Throttle Body25. Fuel Injection Pump35. Throttle Valve45. Oil Pan
6. Camshaft Oil Feed Pipe16. Idle Air Adjuster Screw26. Engine Oil Dip Stick36. Cylinder Head46. Oil Drain Plug
7. Cam Lobe17. Fuel Injector Pipe27. Fuel Pump Damper37. Exhaust Manifold47. Oil Pressure Relief Valve
8. Camshaft Bearing18. Fuel Injector28. Fuel Filter Bowl38. Engine Mounting Support48. Crankshaft Damper
9. Exhaust Valve19. Control Shaft29. Oil Filter Bowl39. Piston49. Injection Pump Drive
10. Heater Return Line20. Breather Outlet30. Oil Pump40. Flywheel50. Visco Fan Coupling


The engine, or, more accurately described as an internal combustion engine works on a mixture of gasoline and air to produce power to turn a shaft that turns the wheels. Major components are listed below.


Smaller components

Related components

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Describe common maintenance procedures, and common faults that may occur. Describe how these may be diagnosed and resolved. Again, include diagrams, photographs and explanations. Where possible, include measures, tolerances, weights etc.

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The engine and manual transmission weigh about 500 pounds.

Using sedan engines

Dan Caron says: the 280 SE/A is correct for the 1970 and 1971 280 SL cars. The SL engine and SE engines are virtualy the same anyway. Small differences in the plumbing and manifolds but nothing all that much. Now the 280 SL euro engine from '68 to '69 is a different thing. Higher lift cam and longer duration. About 10 more HP. So your car can have a 280 SE/A engine and be 100% correct.

All engines have a 9 as first digit of the 2nd group, e.g.:

 130.920 280 S (carb) sedan
 130.980 280 SE/SEL (injection) sedan/coupť/cabrio
 130.983 280 SL Pagoda
 130.923 250 sedan and 250 C coupť

I recently looked at a 1970 280 SL. The engine block number was not 130.983. The block said 280 SE. I've read that it is not uncommon to replace the original engine of a 280 SL with a 280 sedan engine, which appears to be the case here. My question is, is there a difference in the engines?

I once had a couple of W 111 engines, I can say that they looked "exactly" like my 230 SL engine to the point where if one of them were in my Ď65 230 SL, you couldn't see the difference ( I don't know about horsepower). If I were purchasing a W 113 I would only do so with the carís "data card" in my hand and I would check every components # to be sure it was 100% percent original because you surely can find many 113's, so you may as well get an original for price appreciation.

The only difference I have found between the SE & SL engines is that the SEís do not use a tachometer. So, the gear set that drives the oil pump & injection pump would be different. Only in that the SL vertical gear has a shaft that will accept the tach cable. The SE gear has no shaft. The housing it sets in is blocked off with a cap. Also, the aluminum brackets for mounting the motor mounts are different. If you put an engine from an SE in an SL use your old brackets. The SE brackets will raise the engine higher & you could dent your hood. Otherwise everything else is the same. SEs & SLs engines both had early & late versions & standard or automatic transmissions.

A 280 injected sedan engine has the same performance of a 280 SL one but has some differences as pointed out.

Are there other years and models of Mercedes that can be considered as donors for an engine that would be a basic "bolt-in" replacement for ours? If so, what years and models are those, and what do we need to watch out for (I assume the mechanical speedo drive is one issue)?

Pete Lesler: There is no actual direct coorelation from engine numbers to chassis numbers, unless you have the original build card with the car. Engine numbers are sequential, and usually are a few hundreds of digits lower than the chassis numbers, accounting for the different numbers given to automatic trans models and manual trans models. You would need the IBM build card furnished with the car to verify engine swapping.

In restoring my '64 230SL, I'm attempting to keep it as original as possible. The original color on the engine block was apparently a dull red-orange. My machinist thinks it would look better painted black. Any opinions? Were original blocks ever painted black?

The engine block should be black. The red color is actually a primer coat, as the original black has worn off.

Does anyone know the correct torque wrench setting for the two bolts which hold on the oil pump? More generally, is there a more comprehensive table of torque settings than the one in the Service Manual?

The "Tabellenbuch Personenwagen Ausgabe 1969" (Book of Tables, passenger cars, edition 1969) lists a lot of torque settings (in mkp) for the engine and the whole car, but does not have a torque value for the oil pump (except for the V8s, where the pump is attached to the crankcase).

Hans Strom: in general, when one cannot find the specific tightening torque (moment) setting in the factory workshop literature, one reverts to the general ISO norm for torque. The following applies then [all in Nm] (Newtonmetres):

ThreadClass 8.8Class 10.9Class 12.9
M66 - 118 - 1610 - 19
M815 - 2821 - 3825 - 47
M1030 - 5541 - 7650 - 92
M1251 - 9572 - 13385 - 159

Class 8.8 is the most common quality in our cars

I have found a number cast in the block, left front, just above the oilpan flange, and ahead of the engine mount: 1290110001. Can this tell us what kind of block I have? All the other engine parts (head, injection pump, distributor, cooling fan) have part numbers correct for a 230SL.

Tom Hanson: a 129 casting number quite likely indicates a 250SE/SL.

I have an engine with the correct original number as per my data card. The engine does state on a separate label "DAIMLER BENZ ORIGINAL AUSTAUSCH MOTOR". This means original replacement engine.

It is possible that the original engine number was stamped into the exchange engine by MB when the customer ordered his new block. This would make some sense, although at the same time, MB would then take a risk that more than one block with the same number would be in circulation. So more likely is that the shop that fitted the block, stamped in the data card number in the block, at customer's request.

Achim: to answer your question: yes! Exchange engine means that a new (or factory rebuilt) engine was ordered by the dealer when the customer/owner came into the shop with his blown or bad engine. When the new engine came in, it got the number of the old engine, basically your data card engine number stamped in by the authorized MB shop. The old & blown engine went back to Mercedes and was then rebuilt too, got a new "DAIMLER BENZ ORIGINAL AUSTAUSCH MOTOR" label but no number until it was then sold ("exchanged") again.

Would that mean there was some kind of punch kit that the dealer used to punch the number into the block? Would there be any such kit available? I would like to stamp the vin # back into the front frame rail near the air filter canister on my SL, which had the entire front end replaced(firewall to front) and the vin # was never stamped there.

Achim again: I think so. The well equipped MB shops had (or have) a lot of nice tools. As they do car-accident repair as well (at least in Europe), I suggest they also have the number punch kit.

I doubt that this punch kit was available for the free market but only to MB shops. Otherwise this would have been the source for a lot of fraud, for example after theft of a car.

Mercedes Benz offered and still offers the possibility to redo your individual engine. That will be done in the Berlin engine factory. All specs are the same as for a new engine and it is considered an "Original Mercedes Austauschaggregat" with full factory warranty. Your local dealer will pack the engine in a special box, send it to Berlin and after some weeks you will get the engine back. That is the way to go if the engine is bad and you want to stay original, but getting a "new" engine. Price three years ago US$12000. I think it is a good deal for a real original car. So your car is really one of a kind.

The number stamped into my block is exactly the same type of font, size and patterns as my other MB cars. I doubt that any shop would be able to do this. Furthermore, the plate on the block also has this number on it and also in the proper size and format. this plate is riveted to the block. The datacard copy from MB archive has a rubber stamp on it '14 Oct. 1964'. The car came to South Africa not much later than that. Perhaps the motor gave the ghost while still under guarantee and MB replaced it then? I really think that the numbers for this motor must have been done by the factory unless they supplied a specialized kit and stencil so that any dealer could do this. So, all the numbers match and I consider my car original, engine and all. It would be easy to remove the 'ORIGINAL AUSTAUSCH MOTOR' label but I am not going to.

Dan Caron, on originality of engine: ever look in Hemmings or any other large publication for cars or parts? Ever notice in the cars for sale where it specifies original engine or numbers matching car? Ever notice where it says this in the MB section? No? That's because it doesn't matter beans for the most part. If it did , the sellers would be stating this and the buyers would be paying a premium. As long as you have the correct style of engine such as 127, 129 or 130 fuel injected. It really doesn't make much difference if the block came from a sedan or coupe as they're still the same engine. Non 113 cars have different plumbing and hoses for different applications but the main components are eventually the same. These aren't Corvettes, Hemi Cudas or Shelby Cobras etc.

Now we are on the subjects of weights, how much does a 130 Pagoda (280SL) engine weigh ?? I am due to pick one up tomorrow (not literally speaking) and would like to know what to expect ... I would guess something like 200 kilo's?

My 280SL has had a mercedes re-built engine installed, and the block no longer has the engine number on it (the to tell if it is an SL or SE motor. I understand that the SE has a different cam and puts out about 20hp less than the SL, but is there a way to tell which motor I have without pulling anything apart? The motor runs a dream, so I ideally don't want to change anything, but it would be nice to know what I have.

Dan Caron: to my knowledge they're basically the same. Some things are changed a bit to conform to the different body styles but the innards are the same.

Tom Hanson: they are basically the same. The car probably had a factory short block installed at one point (common on the 280) and someone didn't stamp the engine number back in. Any other difference would be somewhat insignificant.

Pete Lesler: Only true if your 280SL is a Euro spec car. All US cars used ''08" or '01 or 05" cams. Euro cams were marked "09" until 1970 and "02" until the end of production. The difference was 15 SAE HP. Or 10 DIN HP. There were calso differences in the fuel in jection pump and no emissions whatsoever on the Euro cars, So the cam was only part of the increase in HP.

Joe Alexander: Hello Pete, I think some early USA 280-SL's may hve been equipped with the 09 camshaft also. I have seen an original USA 1969 280-SL with The "09" camshaft.? There may have a brief period before stronger USA emission regulations took place. I cannot find any distinct documentation on a strictly separate european or USA camshaft. Your right on the "02" camshaft. It was probably the latest improved material and according to the data book, had larger diameter bearing journals. Anyone wishing to use a "02" camshaft would also have to invest in the four new cam supports also.?!

Pete: I think you may be correct on your statement about some of the early cars may have some 09 cams installed. I took an engine out of a 1968 300SEL-2.8 and low and behold it had the 09 cam. I am convinced that it was a US spec car. But is was a very early car. The Euro 300SEL -2.8 engine 109 chassis all had the 09 cam installed. Probably to compensate for the extra weight. If you switch over to the "02" cam you must replace the four cam bearings as well. I have done this on my race car, it works fine.

Would a 1968 250SE engine (engine prefix 129.980) fit into a 280 SL. I know 250SL's engine is 129.982.

Tom Hanson: it will fit, more or less. You'll run into alot of external accessories that have to be changed.

Pete Lesler: like a glove, providing you replace the oil filter housing from the 280 engine as it uses a differnet style poil cooler. But be careful, the engine wire harness may be different. The 1968 250SE may have have a different style emission system, and the fuel injection pump may or may not have the fuel shutoff solenoid. I still think this can be done, but you are always better off with the corrrect engine.

Joe Alexander: The 250-SE engine compared to the 280 SL engine, is physically the same on the outside. Even the exhaust manufolds are the same. The exceptions are; the oil sub-pan may be slightly smaller, the intake manifold could be slightly different, and the flywheel could also be different. None of these differences will prevent a transplant. The one item that will make a difference are the aluminum engine supports which are different on SL's. These must be changed before setting any sedan engine in a SL. Any engine accesory such as intake manifold, alternator, can be interchanged between the two engine types. All M127 (230-SL or sedan) and early 129 (250 SL or sedan) engines had crankshafts counterbalanced to the flywheels and dampners. The later M129 (250-SL and sedans) and M130 engines (280-SL and sedans) had balanced crankshafts with balanced flywheels and dampners. Never mix the counterbalanced flywheels with the later balanced flywheels. The 280 series engines (M130) developed more horsepower.

Do you know the M129 engine serial number after which the crankshaft and flywheel counterbalancing method ws changed? My '67 250SL has a 250SE sedan engine at this point.

Dan Caron: theyíre all the same. Only the 127 was balanced as a unit.

Joe Alexander: hello John, I do not know the engine number for the change. If someone with a M129 dealer parts book will look up the crankshaft it will show the change. Here are some facts; crankshaft #108-031-08-01 was a counter-balanced crankshaft (earliest 250-SE, SL series). The later crankshaft is the same as used in the M130 engines the number for this is #114-031-00-01. This is also verified by the fact that the M129 series engines used two different types of main bearings Glyco #H705/67 and the later Glyco #H790/7. In addition, it appears two different early counter-balanced crankshafts were used, one for the automatics and one for standards. The counter-balanced standard crankshaft number seems to have been #108-031-05-01. In comparison the later balanced crankshaft was used in both the standard and automatic M130 engines. The easiest way to check and see if your crankshaft is the early counter-balanced or balanced is to take a flashlight to the front vibration dampner from below. If the vibration dampner has three equal size masses on the back it is the later balanced version. If it has one large mass it is a early counter-balanced arrangement. Maybe another list person can give us a engine number for the change. I suspect that the latter crankshaft is the only one available. Dan check your books on this one.

Dan: well, you may be right. Itís not something Iíve ever run into. I guess thatís what makes these cars interesting. I donít have a 129 engine book so I canít say. Iíd be inclined to want the crank thatís the later style - itís probably better.

Joe: I think you right here, the later crank seems to have an improved design for lubrication. All balanced componants makes sense also.

On freeing a seized engine: best bet is to remove the head and use a wood 2X2 scrap lumber and a hammer to loosen the piston heads. Most likely seized due to the corrosion between the rings and the liners. But 8 years is not long enough for the engine to seize unless the chain is snagged or timing is off.

Pete Lesler: the manual trans crank was replaced by 108-030-4201 and it was good for all M129 engines, 980, 981, and 982. It was installed on 129980 engines after 004790, and, I assume, all 129982 engines. The new automatic trans crank part number is 108-030-4301. Interestingly it shows only installed on 129980 and 129982 engines. The footnote indicates that it was installed on 129980 engines starting with 004790. I assume, therefore, that all 129982 engines had the later cranks. In checking for part numbers for the harmonic balancer, the only part number I have listed is 108-031-0203. It, apparently, is installed on all engines. Now here is the mystery: I thought all M129 cranks were drilled to accept a clutch pilot bearing. If so, and if the harmonic blancer is the same for all engines, why then is there a different part number for manual and automatic trans cranks?

Dan: the difference is minor yet there is a difference. The dowel pin that locates the flywheel is longer on the standard crank. I think all cranks are drilled at the back for either pilot bearing or the nose of the torque converter or fluid coupling.

Joe Alexander: thanks (to Pete) for the in depth information. This kind of information is lost without lots of research. For someone like John, with a 250-SE engine in his 113 the data can be very important someday. In regards to the mystery here is some additional information. I have a dealerís W108 engine parts book dated 1965. It clearly shows the counter-balanced crankshaft and flywheel with the large single mass. As you indicated the crankshaft is different for the automatics (108-030-2501) and the standards(108-0302401). The key here is there is no part number listed for the vibration dampner for these crankshafts. Apparently the factory supplied only the complete crankshaft "with couterweight" assembly! So if all later crankshafts were balanced then there would be only one front counterweight number for these later cranks!?
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