Let's talk about engines - PeachParts Mercedes-Benz Forum

michaeld · #1 05-17-2006, 12:47 AM

I have found that it is pretty difficult to get a lot of detailed information on classic Mercedes engines (pre-80, as defined on this forum) from the Internet beyond the basic specs.

I would like to learn more about the many other Mercedes-Benz engines.

I thought it would be real interesting to have a description - and perhaps even a discussion - of Mercedes-Benz engines.

Here are just the US market engines: M100, 108, 110, 114, 115, 116, 117, 121, 127, 129, 130, 180, 189 (and of course the diesels: 615, 616,617).

I imagine that Mercedes-Benz had a reason for building each of these engines. Beyond the technical sheet info (hp, torque, etc) I would like to know more about the overall experience of these engines. What's it like to simply drive them (acceleration, smoothness, etc)?
What's it like to maintain them? What's it like to do basic service on them? Also, what do you like/dislike about your particular engine? What's "the word" on your engine from MBz mechanics?

michaeld · #2 05-17-2006, 12:54 AM

I thought I'd start w/ my own engine: the M117.986.

I bought my 1977 450SEL (4.5L M117.986 engine) with 124,000 actual miles on the odo and have put about 3700 miles on it since.

My US federal engine has 180 hp and produces 220 lb/ft of torque at 3,000 rpm. Somehow it feels a lot more powerful than my '90 Cadillac Fleetwood, which had a 5.7L/350c.i. engine that had 175 hp and produced 290 lb/ft of torque. The 77 450SEL is fitted with the K-Jetronic injection system. Combined with the 3 speed tranny, I feel that my car has more-than- adequate acceleration (particularly considering it's moving more than 4,000 lb of weight). At highway speeds, acceleration is magnificent; from 75mph upward, this car MOVES faster than any I've owned. In traffic - particularly when I'm in one lane at a light and need to get into another lane quickly - there are times when I wish I had a 6.9, but for the most part my 0-45 is adequate; I believe I have nearly as good of a 0-45mph acceleration capability as most cars on the road.

My 450SEL was a one-owner car that belonged to a medical doctor. I found all the service records since the car was brand new in the trunk. Other than having the right side cam shaft, 8 rocker arms; and a new oil tube replaced at 87,000 miles, the engine has not been opened. The starter, alternator, and all pumps on the engine were replaced - as well as the front suspension and the ACC Servo - w/in 10,000 miles of my taking over the car.

Shortly after buying the car, I realized that the original radiator was partially blocked, and installed a new radiator core. Other than that, all I've done is a couple of oil changes.

From what I have read on this forum's library, the M117 is an excellent engine. The bottom ends are indestructable. It has a cast iron block with aluminum heads. A MBz mechanic once told me the M117 had the weakness of plastic timing chain guide rails which were MUCH more likely to break than the double-rowed timing chain (though I've never confirmed this). Other than that, I've never heard a negative word about the engine. I am planning to replace the timing chain at about 180,000 miles (unless I hear tell-tale clanking that tells me I need to do it sooner). At this point, I have come to trust that my engine is in good working order; it is currently my only car.

Thus far, I've found parts have been more expensive than standard US parts - but internet shopping has kept things reasonable. I'm learning more and more about mechanics and auto-electric in order to do more of my own work.

My only projects at this time for my car are: 1) replace my brake master cylinder; 2) fix the switch for the right rear window; 3) fix the power door lock for the right rear door (it doesn't properly lock the car after very short drives); 4) do some ACC system work from the console; 5) grease the sunroof rails.

GaryF · #3 05-17-2006, 04:59 AM

Quote:

Originally Posted by michaeld

A MBz mechanic once told me the M117 had the weakness of plastic timing chain guide rails which were MUCH more likely to break than the double-rowed timing chain (though I've never confirmed this).

I think all 116 & 117 engines are double row timing chains, the single chain didnt arrive until later and these can be converted to double from what I've read. It was probably Tomguy or someone else knowledgeable that said the original chain guides are fine because they're metal/plastic but it's newer replacements that can fall apart if the chain slaps.

I'm amazed by the reliability of my '73 car which is down the the engineering of the whole car not just the engine. I'd like my V8 to sound like a V8 but that's just not the character of these cars.

cth350 · #4 05-17-2006, 08:02 AM

If your habit is to hit the accelerator hard, then waiting for the timing chain to make noise isn't the way to go. As a regularly scheduled maintenance procedure, you should be checking the valve clearance and the valve timing.

Also, when laying out the engine numbers, they weren't assigned in numerical order. Also, some motors got major revisions, so a more accurate list might be more like

180.I 180.II ... 130E, 130V 116 CIB 117 CIB ... 116 LAB 117 LAB ...

Where the 180 series went though major modifications from 1952 to 1969. The M130E is fuel injected, but the M130V is carb'd. The 116 with a cast iron block is very different from the light alloy block.

For descriptions of each motor, look for the "introduction to service" manuals that appear on ebay constantly. The oldest ones are for the introduction of the finnies, the 230SL, 600, and 1965 model year. They appeared annually as of 1968, but ocassionally had a special edition for car introductions.

As a for instance, the only printed service manual you'll find for the M123 (the successor to the M130V) is in the "Introduction to service chassis 123".
This book was published towards the end of 1976 and is separate from the 1977 Introduction to service. The same thing happened for the 250E & CE. This is the only benz publication for the M114E motor.

-CTH

Tomguy · #5 05-17-2006, 09:45 AM

The m116 and m117 cast iron blocks (3.5 and 4.5) all had double-row timing chains. However, at 145k miles, my chain had 12° of stretch (a LOT) so I replaced the chain. I did not replace the guide rail.

For my 4.5 (117.984), It isnt the off-the-line power that makes this vehicle stand out (And mated with a 3-speed auto, with a first gear that can take you to nearly 60, it's obvious it wouldnt be). When you are cruising at 70-80MPH and put your foot to the floor, this is where the 4.5's shine the most. It's a joy to drive and experience.

It's very easy to work on, in my opinion. Parts are plentiful/inexpensive and the engine is known for its reliability. When people ask "What kind of carb does it have?" and I say "It's actually stock electronically-controlled fuel injection" they do a double-take. The 3.5 iron-block, its earlier/overseas counterpart, shared the same basic concept but was some 30mm shorter. Due to its shorter stroke it could be revved higher (as the piston didnt have to travel faster at the same RPM in order to cover more ground). The early 3.5 and 4.5 had similar HP figures, but the 4.5 had more torque. Due to rear-end and transmission gearings (3spd on the 4.5, 4spd on the 3.5), some people feel the 3.5 has more "Poke" than a 4.5 off the line. According to stock numbers, 0-60 is some 9 seconds for a 3.5 and 11.2 for a 4.5. With the same gearing however, a 4.5 would likely beat the 3.5.

The basic block and crank design from the 3.5 was carried to the 3.8 and 4.2 aluminum blocks. The block has the same dimensions, and I think the crank is the same. Otherwise it is a pretty different engine. The same goes with comparing the 4.5 to the 5.0 and 5.6.

michaeld · #6 05-19-2006, 12:39 AM

Just to make sure you are aware: I just put the engines in numerical order for ease of quick reference; it frankly didn't even occur to me that someone would think this was the order of construction.

I was hoping to learn more about the many other MBz engines, but as it is, I HAVE learned more about my own (4.5L M117). Tomguy, you mention your engine is a M117.984 - is that from a 73-75 Euro? I'm not familiar with it.

Do I understand correctly that the M117 (including the '76-80 117.986) have metal timing chain guide rails? That would be nice to know! From my readings, about the only thing that can kill these durable engines is a failure to deal with the timing chains. I want to wait; but I don't want to wait too long! As per cth350, I DO intend to inspect my valves, but not until the appropriate service interval. But, while I am a gentle driver (I pull away slowly from one stop and then cruise to the next one to spare both my powertrain and my brakes) my driving only counts for a small fraction of the mileage on the car.

I agree with Tomguy's assessment of the true power range of these engines: it seems that Mercedes did not build the M117 to burn rubber off the light, but rather to blow away lesser engines on the freeway. I appreciated the comparison be: 4.5L and 3.5.

Tomguy · #7 05-19-2006, 01:01 AM

Michael: The timing chain rails may or may not be metal-backed rubber in yours. If they were ever replaced by a PO expect them to be plastic. It's easy to remove the valve cover to check. I highly suggest you do so!

The 117.984 is what went into 108 chassis. 8.0:1 compression ratio stock (I think the 117.981 was the 8.8:1?) and the "hot" cams. The 117.985/986 were the 8.0:1 k-jetronic cars with calmer (and hydraulic) cams. My 4.5 is even more potent than a euro-delivery 4.5 I believe - the euros were 8.8:1 with the same cams as the early US-Specs, mine is currently almost 10:1 with the 3.5 heads and cams I have on it. The end result is even better throttle response at higher RPMs.

michaeld · #8 05-20-2006, 01:08 AM

Tomguy,
Sounds like you've got a pretty nice ride. I myself am content with staying under the "high octane" compression level. I dare say I drive rather like your average grandma.

I'd like to be there to see the look on new muscle car drivers' faces when your 280 shows them what an old Benz can do, though!

Tomguy · #9 05-20-2006, 01:20 AM

Michael, I've been beaten off the line a few times. But when, say, going up an incline at 60+ MPH, those riceboys don't know what hit them. I remember being cut off by some teen in a Honda with a fartcan... It was going up a large hill (Morgan Highway for you NEPA dwellers). I stayed glued to his ass and he was probably wondering how the hell a rustbucket like mine was keeping up. This was BEFORE the new heads and cams!

When I had the stock heads, I tried 87. It was fine at idle and low throttle, but when I gunned it, Quicksilver wasnt as quick. I didnt sense pinging at all, she just didn't move in 2nd at high RPMs like before. It was only 2 gals of 87 when I was on empty to test out - filled her up with 93 and the full-throttle, kickdown power was back. Stock heads and timing may be fine with 87. But I wouldnt even TRY 87 with my current setup. She needs some paint and rust repair... but boy, she's mine, and I love her

michaeld · #10 05-20-2006, 10:02 PM

Tomguy,
I could tell you loved your "old girl" (that's what I call mine, BTW) before you said the 'L' word. A long history of posts that reveal both knowledge and passion for these cars tipped your hand there, my friend!

It's kind of like we were discussing earlier: these cars truly begin to reveal their soul - and their real glorious majesty - at cruising speed. Apart from the M100s, I don't think ANY of the Benz saloons were meant to be hot off the line. These aint cars for punk kids trying to impress airheaded bimbos at stop lights!

I love rice burners - in motorcycles (although I WOULD love to have a Beamer). In cars? Even the Lexus cars radiate a plasticy, everything-that's-wrong-with-the-times, impermanence to them. In 20 years nearly all of them will have long since ended up on the scrap pile.

There's horsepower, and then there's torque. I think a lot of modern car marketers - focused soley on the whims of the market - have come to believe that the former sells, and the latter is irrelevant. Here's one link re: that subject - http://www.modernracer.com/features/hondaprelude1993.html. Personally, I think the Asians are MUCH more guilty of this than are Americans. Combine that with a rear end/transmission set up for improved mileage, and you get a dog on the hills. I can't tell you how often I've had some riceburner scream past me on the freeway, only to watch them struggle up a steep grade. It always makes me

. I use to have a 70 Ford Galaxie 500 with a Cobra Jet 428. I loved the look on the faces of those rice burners when I went by them with contemptous ease up the slope - and of course I had a LOT more if I wanted to really open up the can of whoopass!

I used to have a 90 Cadillac Fleetwood Brougham. It had a 350ci 5.7L; and it was GUTLESS compared to my 77450SEL. I remember my shame

the first time I had to lower the gear to go up a hill with any kind of style! My 450SEL eats hills alive and I can hear her saying, "Give me another one!" I love everything about my car, excepting the fuel economy. I've never felt this way about any car I've ever owned. She's my "fortress of solitude."

I'm like you, in several ways (which is probably why I enjoy reading your posts so much). Unfortunately, I don't have a lot of money to throw into my car right now (which may be unlike you!), but I love it. I am fixated on doing whatever I can to keep my old girl well-maintained. When I have more disposable income, I won't be putting it into shiny paint and pretty wheels; I will invest it in the quality of her engine.

I'm glad to hear that your car doesn't ping at low octane; it's a sign of rugged quality for a pre-74 car. My 70 Ford was the same way on 87; it would run, but it wouldn't roar. I doubt if my stock 77 M117.986 would derive the same benefit.

Tomguy · #11 05-20-2006, 10:48 PM

Quote:

Originally Posted by michaeld

Unfortunately, I don't have a lot of money to throw into my car right now (which may be unlike you!), but I love it.

If I had the money, she'd be restored completely by now. But I don't. Despite her flaws, I still think she's great.

I'd love to hear from m100 owners comparing 6.3 and 6.9's. Even m110 and m130 comparisons. How the MB engines evolved throughout the 60's and 70's, and how they're usually all high-revving engines, save perhaps the M100's.

michaeld · #12 05-23-2006, 04:22 AM

Quote:

Originally Posted by Tomguy

I'd love to hear from m100 owners comparing 6.3 and 6.9's. Even m110 and m130 comparisons. How the MB engines evolved throughout the 60's and 70's, and how they're usually all high-revving engines, save perhaps the M100's.

Yeah; THAT'S what I was really trying to get at in this thread, but on the broader scale. I wanted to have a basis to look at each of the various MBz engines and learn what were the good points and bad points of each, and the rationale for their manufacture.

Sigh

I suppose I'll just have to find some book that lays it out for me.
Mike

jahawk · #13 05-25-2006, 10:10 PM

How does a model M130V engine type 130.923 differ from a type 130.920? Is it specific camshaft installed?

senorunimog · #14 05-26-2006, 12:32 PM

I have several vehicles with an M130 engine. When they run right they are great engines, fairly smooth with some pleasant valve clicking.

They have several flaws, The M130 is essentially the same casting as the M180 (2.2L) to be able to fit larger cyls in they sqeezed them all together, and eliminated cooling passages between them. This makes cooling somewhat of an issue, but not too big as long as you have the radiator working right.

the other large flaw is in the oiling system. The first versions of this motor have insufficent oiling to the cam shaft, as a result any low oil pressure causes the cam to eat itself, from the rear of the motor foreward, grinding flat spots in the cam lobes. I had that happen to me yesterday as a matter of fact, had to replace the rocker, and filed down the cam lobe as smooth as i could get it, i hope it holds.

Mercedes addressed this issue as of motor #075 800 Where they increased oil sump capacity, added a larger oil pump, increased the oiling groove on the front of the cam, increased the cam oiling tube from 8mm to 12mm and drilled larger drainage holes in the block and head.

Tristar1959 · #15 05-29-2006, 09:33 PM

Senor 'mog -

I had heard of that loss of cooling between cylinders before, and am now wondering if the M114 was also better in that respect.

I am replacing a very tired M130/auto in my '72 250C with a totally rebuilt M114.920/stick that I've had in my (now rusting-out) '70 250. Despite the downgrade from a 2.8L to a 2.5L, I actually expect to do better; with a boring and head shave, it's a medium-compression 2.5x L engine, plus lovely Webers instead of Zenith-INATs, and a Timevalve stainless exhaust. I've never had any cooling problems, and the block was boiled out at rebuild, of course - but I was just wondering how the 114 compared, in that respect ('tween-cylinder flow).

Parenthetically, I did install M130 double-row chain gear throughout to replace the M114's single-row, when I rebuilt - totally exact fit.

Stan