500 SEL diesel? - PeachParts Mercedes-Benz Forum

Beirut Brit · #1 10-20-2020, 03:19 AM

Hi
I'ts one of those posts, i'm afraid. the guy who's about to buy a car but wants to check something.

I have my eye on a 500 SEL 1983 but weirdly, it seems to have a diesel engine.

According to the Wiki page of the W126, there was no diesel engine for the 500 SEL, at least not in the graph where it lists all the variants.

The car is quite some distance from where i live and it's lockdown here so i wanted to know from members what could/should the diesel engine be in that 1983 model.

From the picture (poor quality) it looks like a five in line diesel engine popular with the 240D model. I'm wondering whether the owner dropped it in.

Also, if anyone can tell me what the difference is between a 500SEL and a 300 SEL i would be terribly grateful.

thanks for your patience

MJ in Morocco

t walgamuth · #2 10-20-2020, 07:51 AM

Hi MJ. I had the pleasure of visiting your country (Morroco) back in 1973.

a 500 SEL would have had a five liter gas v8 from the factory at least in the US. A 300 sel would have a six cylinder three liter gas engine. If equipped with a diesel it would have carried the label on the trunk 300SDL. If it is a swap, the rear differential will be a good deal taller than stock so will offer leisurely acceleration but outstanding economy.....perhaps in the high thirties in mpg which is outstanding for a car of that size and comfort. The 500 would also have come with more luxury options such as leather seats and power windows.

Based on my experience here in the US it would appear you have a car which has had the diesel swapped in. The six most likely is a 617 diesel which might be turbo or not. It should give the car similar performance to a 240d if not turboed, and similar to a 300 turbo diesel station based on estimated weight.

The swap should have been pretty much a bolt in. The 617 turbo motor was offered in the S class from the factory too.

When I was there in 1973 I saw quite a few old American built cars such as Chryslers being worked as taxis running some sort of modest four cylinder diesel. They would run between towns filled up with wiry built Morrocans.

Beirut Brit · #3 10-20-2020, 08:47 AM

Quote:

Originally Posted by t walgamuth

Hi MJ. I had the pleasure of visiting your country (Morroco) back in 1973.

a 500 SEL would have had a five liter gas v8 from the factory at least in the US. A 300 sel would have a six cylinder three liter gas engine. If equipped with a diesel it would have carried the label on the trunk 300SDL. If it is a swap, the rear differential will be a good deal taller than stock so will offer leisurely acceleration but outstanding economy.....perhaps in the high thirties in mpg which is outstanding for a car of that size and comfort. The 500 would also have come with more luxury options such as leather seats and power windows.

Based on my experience here in the US it would appear you have a car which has had the diesel swapped in. The six most likely is a 617 diesel which might be turbo or not. It should give the car similar performance to a 240d if not turboed, and similar to a 300 turbo diesel station based on estimated weight.

The swap should have been pretty much a bolt in. The 617 turbo motor was offered in the S class from the factory too.

When I was there in 1973 I saw quite a few old American built cars such as Chryslers being worked as taxis running some sort of modest four cylinder diesel. They would run between towns filled up with wiry built Morrocans.

hi
Im sorry to disappoint you but im not moroccan. I'm a brit.
But i'm enormously grateful to you for giving me all that info. I was pretty sure that the five cylinder engine had been swapped at some point.

So basically the 500 is the same car but just with a bigger engine than the 300.

thanks so much

MJ

ScooterABC · #4 10-20-2020, 10:31 AM

1. What is the VIN of the car?
2. Read this: https://en.wikipedia.org/wiki/Mercedes-Benz_W126

Beirut Brit · #5 10-20-2020, 02:36 PM

Quote:

Originally Posted by ScooterABC

1. What is the VIN of the car?
2. Read this: https://en.wikipedia.org/wiki/Mercedes-Benz_W126

I have read it, of course. Doesn't seem to give much info about the 500

and somewhere i have read that the 500 DID have a five cylinder diesel engine in it, but it's not on the graph of that wiki page. confused.

Reading it, it gives the impression that the 500 is simply a 300 with a bigger engine.

ScooterABC · #6 10-20-2020, 02:50 PM

No. A 500 SEL is a gas powered V8. This car has had a transplant. The 5 cylinder diesel was ONLY in the SD, not the SDL... Not the long wheelbase cars.

Tomguy · #7 10-20-2020, 03:01 PM

The VIN will tell you whether this car is:
1) An engine transplant victim,
2) Misrepresented.

There is no 3. a 500SEL (w126) has a 5.0L M117 V8, there is no 5 liter Diesel. There was a 3 liter Diesel w126, the 300SDL. This car might be a 300SDL. The VIN would tell you that. The VIN would tell you if it was an original 500SEL as well. But if it now has a Diesel, the VIN will not tell you what Diesel is in it, and how well or poorly the swap was executed.

Beirut Brit · #8 10-20-2020, 03:14 PM

Quote:

Originally Posted by Tomguy

The VIN will tell you whether this car is:
1) An engine transplant victim,
2) Misrepresented.

There is no 3. a 500SEL (w126) has a 5.0L M117 V8, there is no 5 liter Diesel. There was a 3 liter Diesel w126, the 300SDL. This car might be a 300SDL. The VIN would tell you that. The VIN would tell you if it was an original 500SEL as well. But if it now has a Diesel, the VIN will not tell you what Diesel is in it, and how well or poorly the swap was executed.

Right. great. Some progress. So where is the VIN and how do it use it to establish what this car really is? Is there a site when you can put the VIN in and get all the info ?

thanks

t walgamuth · #9 10-20-2020, 08:49 PM

Quote:

Originally Posted by Beirut Brit

hi
Im sorry to disappoint you but im not moroccan. I'm a brit.
But i'm enormously grateful to you for giving me all that info. I was pretty sure that the five cylinder engine had been swapped at some point.

So basically the 500 is the same car but just with a bigger engine than the 300.

thanks so much

MJ

Pretty much....the SEL though indicates a longer wheelbase with the extra room put in the rear seats...at least in the US.

Sorry about the slipped native country. I'll try to read more carefully.

ScooterABC · #10 10-21-2020, 10:51 AM

Quote:

Originally Posted by Tomguy

There was a 3 liter Diesel w126, the 300SDL. This car might be a 300SDL.

Except not in 1983. I was hoping the poster had the year correct. SDLs started in 1985.

ScooterABC · #11 10-21-2020, 10:56 AM

Quote:

Originally Posted by Beirut Brit

Right. great. Some progress. So where is the VIN and how do it use it to establish what this car really is? Is there a site when you can put the VIN in and get all the info ?

When you find the VIN, the first 6 digits (126.xxx) will tell you the model - you can use the table in the wikipedia page.

As far as finding the VIN, look on paperwork, in the door jamb, interior windshield surround, and cross member in front of radiator.

You might not what you are looking for in this sub-forum - it's for 1979 and earlier cars, which this car is not.

Frank Reiner · #12 10-21-2020, 01:18 PM

Quote:

Originally Posted by ScooterABC

When you find the VIN, the first 6 digits (126.xxx) will tell you the model - you can use the table in the wikipedia page.
As far as finding the VIN, look on paperwork, in the door jamb, interior windshield surround, and cross member in front of radiator.
You might not what you are looking for in this sub-forum - it's for 1979 and earlier cars, which this car is not.

In W126 chassis the VIN is stamped into the firewall, slightly to the right of center.

Idle · #13 10-21-2020, 01:39 PM

When these cars were new there was a lot of noise about how the aluminum V-8 could never be rebuilt. It would just have to be replaced someday.

I don't know if this is true or hype, but it was a popular story that was pushed by Mercedes.

Someone might have just seen the cost of a new V-8, realized a five cylinder diesel would fit (and had one handy) and just dropped it in. This would be quite a project as it would also entail changing out the ignition switch, much of the wiring and perhaps even some transmission parts.

Plus they would have had to pull the diesel from a station wagon to get the self leveling pump on the front of the engine. That is, if they wanted to keep the original suspension. The rear shocks could have also been changed out from the air over oil to standard nitrogen shocks.

Get the VIN. It will tell all.