1990 Mercedes-Benz 300SE Tips and Tricks
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From: MA
1987 SDL; 2001 Chevy 2500HD CC, 8.1L, Allison special order; 1970 GTO LS2, 4L60E, under construction
1990 Mercedes-Benz 300SE Tips and Tricks
Any things a new buyer should be aware of when looking at the above model?
175K, auto trans, everything supposedly works.
Thanks!
175K, auto trans, everything supposedly works.
Thanks!
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Thread Starter
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From: MA
1987 SDL; 2001 Chevy 2500HD CC, 8.1L, Allison special order; 1970 GTO LS2, 4L60E, under construction
I'm just looking for something with good size and reliability...
Do they all take Premium unleaded? The compression ratio doesn't seem high enough to require it on that engine...
Do they all take Premium unleaded? The compression ratio doesn't seem high enough to require it on that engine...
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Yes, Premium only. Honestly though, if this is a concern, this is the wrong car. Everything on these cars is expensive, and the $2 per tank extra on fuel is by far the cheapest part of ownership.
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Thread Starter
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From: MA
1987 SDL; 2001 Chevy 2500HD CC, 8.1L, Allison special order; 1970 GTO LS2, 4L60E, under construction
Been looking at the diesels. Have an offer one on currently. Seem to be very expensive given the price of fuel.
If I could get one that ran on regular gas, I could get another 124 miles per dollar spent on fuel/gas.. Even with 28mpg vs 24mpg...
If I could get one that ran on regular gas, I could get another 124 miles per dollar spent on fuel/gas.. Even with 28mpg vs 24mpg...
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Using regular in a car that requires premium is a false economy, it ends up costing more.
Mercedes are expensive to operate, not the kind of car if you are looking for low operating costs.
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From: MA
1987 SDL; 2001 Chevy 2500HD CC, 8.1L, Allison special order; 1970 GTO LS2, 4L60E, under construction
My math is 100% correct. I was using the standard of 20 gallon capacity for both vehicles. You get MORE value with the gas powered model per dollar spent than with the diesel with prices being what they are.
The mileage figure I provided is correct, just misinterpreted.
Say both cars have a 20 gallon tank, just for standardizing both cars:
Diesel gets 28mpg (84' 300D) which means the range on a 20 gallon tank is 560 miles.
Gas gets 24mpg (91 300SE) so the range is 480 miles.
As of yesterday, per the internet, the cheapest diesel in the area was 3.55 per gallon. At 20 gallons, a fill up costs $71.00.
As of yesterday, per the internet, the cheapest gas was 2.49 per gallon (regular gas, which I used in my original calculation). At 20 gallons, a fill up costs $50.00. With premium, the same fill up costs 56.60. More than your stated 2 dollars per tank.
The difference between 71.00 (diesel) and 56.60 (premium) is $14.40. Take that $14.40 that you already spent filling the diesel to go 560 miles and put it into the tank with premium. That gets you an additional 5.1 gallons, which allows you to drive an additional 122.4 miles. Add the 122.4 miles to the original tank's 480 mile range and you get 602.4 miles vs the diesels 560 miles.
Now, the acutal number cost of the two fuels is NOT important, the SPREAD is. Same thing with the tank capacities.
As my original statement said, you get MORE VALUE per dollar spent with the gas motor given the price of diesel for the last 8 years.
And that doesn't get into the higher initial cost of the diesel powered vehicles either...
The mileage figure I provided is correct, just misinterpreted.
Say both cars have a 20 gallon tank, just for standardizing both cars:
Diesel gets 28mpg (84' 300D) which means the range on a 20 gallon tank is 560 miles.
Gas gets 24mpg (91 300SE) so the range is 480 miles.
As of yesterday, per the internet, the cheapest diesel in the area was 3.55 per gallon. At 20 gallons, a fill up costs $71.00.
As of yesterday, per the internet, the cheapest gas was 2.49 per gallon (regular gas, which I used in my original calculation). At 20 gallons, a fill up costs $50.00. With premium, the same fill up costs 56.60. More than your stated 2 dollars per tank.
The difference between 71.00 (diesel) and 56.60 (premium) is $14.40. Take that $14.40 that you already spent filling the diesel to go 560 miles and put it into the tank with premium. That gets you an additional 5.1 gallons, which allows you to drive an additional 122.4 miles. Add the 122.4 miles to the original tank's 480 mile range and you get 602.4 miles vs the diesels 560 miles.
Now, the acutal number cost of the two fuels is NOT important, the SPREAD is. Same thing with the tank capacities.
As my original statement said, you get MORE VALUE per dollar spent with the gas motor given the price of diesel for the last 8 years.
And that doesn't get into the higher initial cost of the diesel powered vehicles either...
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My math is 100% correct. I was using the standard of 20 gallon capacity for both vehicles. You get MORE value with the gas powered model per dollar spent than with the diesel with prices being what they are.
The mileage figure I provided is correct, just misinterpreted.
Say both cars have a 20 gallon tank, just for standardizing both cars:
Diesel gets 28mpg (84' 300D) which means the range on a 20 gallon tank is 560 miles.
Gas gets 24mpg (91 300SE) so the range is 480 miles.
As of yesterday, per the internet, the cheapest diesel in the area was 3.55 per gallon. At 20 gallons, a fill up costs $71.00.
As of yesterday, per the internet, the cheapest gas was 2.49 per gallon (regular gas, which I used in my original calculation). At 20 gallons, a fill up costs $50.00. With premium, the same fill up costs 56.60. More than your stated 2 dollars per tank.
The difference between 71.00 (diesel) and 56.60 (premium) is $14.40. Take that $14.40 that you already spent filling the diesel to go 560 miles and put it into the tank with premium. That gets you an additional 5.1 gallons, which allows you to drive an additional 122.4 miles. Add the 122.4 miles to the original tank's 480 mile range and you get 602.4 miles vs the diesels 560 miles.
Now, the acutal number cost of the two fuels is NOT important, the SPREAD is. Same thing with the tank capacities.
As my original statement said, you get MORE VALUE per dollar spent with the gas motor given the price of diesel for the last 8 years.
And that doesn't get into the higher initial cost of the diesel powered vehicles either...
The mileage figure I provided is correct, just misinterpreted.
Say both cars have a 20 gallon tank, just for standardizing both cars:
Diesel gets 28mpg (84' 300D) which means the range on a 20 gallon tank is 560 miles.
Gas gets 24mpg (91 300SE) so the range is 480 miles.
As of yesterday, per the internet, the cheapest diesel in the area was 3.55 per gallon. At 20 gallons, a fill up costs $71.00.
As of yesterday, per the internet, the cheapest gas was 2.49 per gallon (regular gas, which I used in my original calculation). At 20 gallons, a fill up costs $50.00. With premium, the same fill up costs 56.60. More than your stated 2 dollars per tank.
The difference between 71.00 (diesel) and 56.60 (premium) is $14.40. Take that $14.40 that you already spent filling the diesel to go 560 miles and put it into the tank with premium. That gets you an additional 5.1 gallons, which allows you to drive an additional 122.4 miles. Add the 122.4 miles to the original tank's 480 mile range and you get 602.4 miles vs the diesels 560 miles.
Now, the acutal number cost of the two fuels is NOT important, the SPREAD is. Same thing with the tank capacities.
As my original statement said, you get MORE VALUE per dollar spent with the gas motor given the price of diesel for the last 8 years.
And that doesn't get into the higher initial cost of the diesel powered vehicles either...
I owned a 300SE, and I never saw 24 MPG, or even close. I was able to hit 20 when driving on the highway only. Even though the 3,0 I6 is very efficient, the gearing is so low on the 300SE(L) models that 80MPH was nearly 4000 rpm.
Also, your diesel price is hugely inflated, so I can see how it would change the outcome of your analysis. Also, your fuel stations must practice strange pricing, 90% of stations have mid grade and regular at 10 cent increments per gallon over regular, while your prices are a bit higher (at 10 cent increments, it would be $54, a $4 premium over regular, which lies nearly halfway between both of our statements).
Even assuming your analysis of fuel costs may be correct, you fail to take into account the operating costs of gasoline vs diesel models, this extends beyond the savings related to spark plugs to the more complicated systems present in the M103 vs a the OM617 or 603.
The fact is, an S class will the the least efficient MB due to its size and weight, and if you want an efficient MB that runs on regular you are left with only one model, the 190E 2.3 (the 2.6 also requires premium). Keep in mind though that engines tuned to run on premium are generally more efficient so that there is no cost savings to buy an engine tuned for regular, all things being equal.
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From: MA
1987 SDL; 2001 Chevy 2500HD CC, 8.1L, Allison special order; 1970 GTO LS2, 4L60E, under construction
My fuel prices were taken directly from the gas staion. No over inflation at all. All my numbers are 100% accurate.
Seems to me diesels are cheaper unitll something breaks, then its all over. Given the age and mileage of the vehicles I'm looking at, the gas will be cheaper to maintain. After all, the only differences would be the engine internals, the external components would have the same durability/failure rate.
If I'm stuck with the ****ty 190's, I'd rather walk...
Seems to me diesels are cheaper unitll something breaks, then its all over. Given the age and mileage of the vehicles I'm looking at, the gas will be cheaper to maintain. After all, the only differences would be the engine internals, the external components would have the same durability/failure rate.
If I'm stuck with the ****ty 190's, I'd rather walk...
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My fuel prices were taken directly from the gas staion. No over inflation at all. All my numbers are 100% accurate.
Seems to me diesels are cheaper unitll something breaks, then its all over. Given the age and mileage of the vehicles I'm looking at, the gas will be cheaper to maintain. After all, the only differences would be the engine internals, the external components would have the same durability/failure rate.
If I'm stuck with the ****ty 190's, I'd rather walk...
Seems to me diesels are cheaper unitll something breaks, then its all over. Given the age and mileage of the vehicles I'm looking at, the gas will be cheaper to maintain. After all, the only differences would be the engine internals, the external components would have the same durability/failure rate.
If I'm stuck with the ****ty 190's, I'd rather walk...
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From: Near Manassas Va
'65 220S, '89 40SEL, 2002 Ford Crown Vic P71
I run regular in mine with no problems.
At that mileage, look for front end wear, check the ball joint boots for cracking, the flex discs, oil consumption. If the oil mileage is a quart every 800 to 1000 miles, you will need to replace the valve guides and have the valves and seats surfaced.
Rust can be an issue as well. A good PPI will help.
It's a big car with a small engine that's geared high. Figure 3000 rpm for 60 mph but the engine is strong so RPM is not an issue. I het around 22 with mostly all mighway miles.
At that mileage, look for front end wear, check the ball joint boots for cracking, the flex discs, oil consumption. If the oil mileage is a quart every 800 to 1000 miles, you will need to replace the valve guides and have the valves and seats surfaced.
Rust can be an issue as well. A good PPI will help.
It's a big car with a small engine that's geared high. Figure 3000 rpm for 60 mph but the engine is strong so RPM is not an issue. I het around 22 with mostly all mighway miles.
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Thread Starter
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From: MA
1987 SDL; 2001 Chevy 2500HD CC, 8.1L, Allison special order; 1970 GTO LS2, 4L60E, under construction
K. I may go look at the car this weekend. The more I look at these diesels, the more I'm convinced the owners think they're made of gold..
Which they certainly are not...
Which they certainly are not...
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Be sure so ask about oil consumption and check for signs of head gasket weakness on that car. Because of the low gearing and constant high RPM I would try to find one that has been running on synthetic oil.
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From: MA
1987 SDL; 2001 Chevy 2500HD CC, 8.1L, Allison special order; 1970 GTO LS2, 4L60E, under construction
I'll see what I can do. Although the mileage seems low and waiting around for a car that's had synthetic probably isn;t going to happen in my time frame... This car seems to be well cared for.
In the 7 years he had it (3rd owner), the waterpump, thermostat, all brakes, distributor cap+rotor, steering stabilizer and battery were replaced.
In the 7 years he had it (3rd owner), the waterpump, thermostat, all brakes, distributor cap+rotor, steering stabilizer and battery were replaced.
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Other things that may go wrong: fan clutch, fuel inectors and/or seats. Check under the hood for any cracked or disconnected vaccuum lines. Make sure the coolant is a pale yellow, not green or pink, most important that he has been using MB or Zerek G05 coolant, any others will damage the cooling system.
Listen for differential whine, most people never service the diff. Also check the trans fluid, people are usually very sloppy about that using cheap fluids, not draining it all, or not changing the filter.
If you end up getting it, I would still go through and change all the fluids and filters. I would reccomend Valvoline Syn 5w-40 or M1 0w-40 for the engine, and the corresponding syn ATF and differential fluids.
Also, check the power steering fluid to see if it is dirty,
Listen for differential whine, most people never service the diff. Also check the trans fluid, people are usually very sloppy about that using cheap fluids, not draining it all, or not changing the filter.
If you end up getting it, I would still go through and change all the fluids and filters. I would reccomend Valvoline Syn 5w-40 or M1 0w-40 for the engine, and the corresponding syn ATF and differential fluids.
Also, check the power steering fluid to see if it is dirty,
Last edited by Untertürkheim; Oct 24, 2008 at 09:05 PM.
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From: MA
1987 SDL; 2001 Chevy 2500HD CC, 8.1L, Allison special order; 1970 GTO LS2, 4L60E, under construction
I'm an Amsoil dealer, so I think I've got that part covered...
Will do. I'd ideally like to get the thing over to my mechanic and even do a compression test on it, but he only works during the week and I don't have any time to get the car there. I may just have to wing it.
Anyway, thanks all for the info. I have a few good places to get started.
Will do. I'd ideally like to get the thing over to my mechanic and even do a compression test on it, but he only works during the week and I don't have any time to get the car there. I may just have to wing it.
Anyway, thanks all for the info. I have a few good places to get started.
