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E46 M3 IR 6SPD|E39 540iA|B6 A4 3.0
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Discussion Starter · #1 ·
I have had the 560SEC for almost three months now. so far it has been problem free and the car is pimp.

the ONLY problem is, it uses wayyyyyyyy too much gas. The power output doesn't justify the fuel economy nowadays, but I am sure it did back in 1989.

I do love the car very much and it has been my daily since I bought it. I would do a M119 swap but the car's body has too much rust, it's not worth it.

I want to swap out my motor to the MB turbo diesel motors and drive her around for a few more years before getting a mint W126.

anyone know what's involved? I need specific details since I am serious about this swap.

thanks fellas
 

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E46 M3 IR 6SPD|E39 540iA|B6 A4 3.0
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Discussion Starter · #3 ·
I don't need another car. I have 4 cars already. Another thing is, I don't want to sell my W126 at this moment.
finding a black on black W126 is not easy task.
 

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2012 CL550 4MATIC Coupe - RIP
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Putting a Diesel in a SEC is like being married to a Playboy bunny with 36DD's and then having her get a breast reduction to "A" cups because you want to save on buying her bra's.

Good Bra's are expensive, just ask any woman.

So are SEC's.
 

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E46 M3 IR 6SPD|E39 540iA|B6 A4 3.0
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Discussion Starter · #5 ·
she is rusted. there is nothing I can do.
good bra does a little.
 

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2012 CL550 4MATIC Coupe - RIP
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Well Dragi is doing a gas to diesel swap on a W124 wagon that he is converting to a shop wagon. I know it's quite involved.

Besides the engine and trans (I believe you have to swap the trans for the different ratios) you need to change harnesses and wiring. Then of course you need to swap fuel tanks and all the lines and plumbing from back to front.

In the case of the SEC, I believe you would need to make all new lines from scratch. I do not know if you would want to (or could) reuse the gas lines. Maybe Jono knows? When you convert an SEL to diesel, there are cars with the same chassis that you can rob parts from that are the same length. This is not the case with a SEC because the chassis is so much shorter.

I do not know if it has been done, because it comes down to WHY?

The SEC was designed to be the penultimate Gentleman's car. Fast and responsive, able to seat 4 in a pinch, but more designed for two. A true autobahn cruiser.

I think you will find that if you yourself have to ask the question you posed, then it will be far too expensive... Let's say it costs 3 grand? (And that is probably low) That buys a lot of gas and if, as you say it is rusted and you are going to junk it in a few years anyways, then why bother? It's a break even.

I used to be Sales Manager here at Rally Chevrolet and when I was on the line I sold trucks of course. The Diesel engine was like 6 grand back then and guys would come in and say they wanted the Diesel for the gas mileage. And I would ask them how many miles they intended to drive a year and then I would pencil out the numbers after they came down from the sticker shock. Also I asked them how much weight they intended on towing, blah blah blah... For the guys that tooled around the city here (Like most Southern Californians do..) it did not pencil out.. For the guys hauling heavy trailers, or driving lots of miles, or both, it makes sense.

Then, when Karen and I (My Ex) went to buy my truck she said "Don't you want to get the diesel?" And I told her the same thing and we talked about how big a boat or trailer we were planning and where we would go with them and she agreed and I ended up getting the 6.0L. Because we ended up getting a Class "A" Motor home anyways.

So do all of the calculations and see if it still makes sense... But from what you are saying, in my mind it doesn't add up.

That's my honest opinion setting aside my disdain for doing that to a coupe.
 

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1987 300SDL
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HEY!
Don't diss diesels cuz we're slow! ('Sides, we're not that slow)
btw, doing a swap for a diesel won't get you spectacularly better fuel econ.

you gassers get, what, 15-18 mpg? 20 max? Diesels only get about 20-25.
alright fine, 30 if you're careful, but really, all that effort for five mpg's either way boggles the mind.
 

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2012 CL550 4MATIC Coupe - RIP
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HEY!
Don't diss diesels cuz we're slow! ('Sides, we're not that slow)
btw, doing a swap for a diesel won't get you spectacularly better fuel econ.

you gassers get, what, 15-18 mpg? 20 max? Diesels only get about 20-25.
alright fine, 30 if you're careful, but really, all that effort for five mpg's either way boggles the mind.
Yes, you just further alliterated my point. if you realize a 25% gain at $3.00 a gallon, you would have to drive a lot to realize the offset that a $3000-5000 conversion would cost. Does the OP have the skills to do the job himself? If not, then add that to the cost.

12,000 miles a year @ 25 miles per gallon is 480 gallons @ $3.00 a gal = $1440.00 per year in gas. (Diesel here in Cali is actually $3.25 a gal)

12,000 miles a year @ 12.5 per = 960 gal @ $3.00 a gal = 2880.00. I am just using easy numbers here.

So that is $1440.00 per year, so a 2-4 year payback for a diesel conversion.. And that's IF you get double the mileage out of it. DOUBLE. Anything less and the payback time is that much longer. The OP said the car was rusted and he was not going to keep it more than a few years, so it really does not make sense to do it if he is not going to keep the car past year 3-4 depending on conversion cost.

True that if he uses Bio-Diesel he will be greener and contributing a smaller carbon footprint, and that is admirable, I just personally don't see it being worth while. But to each his own.
 

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1997 SL500 40th Aniversary 1998 C230 2002 E430 sport 1987 420SEL sold 1989 300E sold
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Yes, you just further alliterated my point. if you realize a 25% gain at $3.00 a gallon, you would have to drive a lot to realize the offset that a $3000-5000 conversion would cost. Does the OP have the skills to do the job himself? If not, then add that to the cost.

12,000 miles a year @ 25 miles per gallon is 480 gallons @ $3.00 a gal = $1440.00 per year in gas. (Diesel here in Cali is actually $3.25 a gal)

12,000 miles a year @ 12.5 per = 960 gal @ $3.00 a gal = 2880.00. I am just using easy numbers here.

So that is $1440.00 per year, so a 2-4 year payback for a diesel conversion.. And that's IF you get double the mileage out of it. DOUBLE. Anything less and the payback time is that much longer. The OP said the car was rusted and he was not going to keep it more than a few years, so it really does not make sense to do it if he is not going to keep the car past year 3-4 depending on conversion cost.

True that if he uses Bio-Diesel he will be greener and contributing a smaller carbon footprint, and that is admirable, I just personally don't see it being worth while. But to each his own.
+1
Sometimes things look a lot different when you do the math and crunch the numbers. alot of people ran out and bought hybrids, some of them paying $4000-5000 premiums and then reliezed that they would have to drive the car for about ten years to break even.
Save yourself the headache, the money, and the aggravation.
Also remember, if you guys have smog inspections, you are going to have to that car inspected/ seen by a state referee because the car is still gas acording to the paper work.
Thats why you can take a 300SD and throw a monster motor in it, and you would never to worry about smog test.
 
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