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Long Commute

Started by JasonP, 29 April 2013, 09:45 PM

JasonP


I love my car.

Drove home tonight up a long hill, hit the beginning of it at around 72 mph, 3,300 rpm - never had to give it more gas, the car climbed the hill at the same speed, the same rpm, the whole time, didn't drop speed at all.

Diesel = Torque = Awesome.

Got the balance/alignment set up for next week. After that, I think I could cruise at 80mph no problem. The engine is as smooth and quiet as silk when I get home. The interstate I traveled home on today has a speed limit of 75 mph, and everyone around me was going at least 80, even the cops. I would look in my rear view mirror and see an army overrunning me. I stayed in the middle lane, let them have their fun.





1979 300SD
Color: 623H "Light Ivory"
1979 300SD
Color: 861H "Silver Green Metallic"
1977 280 E
Color: 606G "Maple Yellow"
-------------------------------------------

ZCarFan

The 300SD does have a "locomotive" like feel to it due to the power delivery esp. under boost, but the OM617 is not a real torque-monster.  Take for example the lowly Chevy 250 L6.  The specs show 110 HP@ 3800 rpm 195 ft lbs @ 1600 rpm .  That's about the same as the OM617, but bringing the torque peak in at a much lower RPM.  I had one in my '78 Nova and it would pull cleanly from idle in high gear and exhibited distinctly truck-like in manners.  About the same economy as the W116 300SD albeit without the safety, style and longevity.

Mercedes had to accommodate a wide variety of markets all with their own (often) arbitrary regulations.  That is how the W116 came to have a relatively small,  relatively high-RPM Diesel vs. larger lower revving engines.  Note that for the flagship models ( 600 and 6.9) they used big low-RPM torquers, regulations, tax penalties, etc in the international markets be damned. :)

As far as practical classics go the W116 300SD is pretty darn good.  Although steady 80 MPH freeway cruising is at the high end of it's comfort zone, mine always worked well at more moderate speeds.  As you know, as you sort out the details, the car is pleasant to drive.

I would personally stay out of the middle lane though.  I think of the middle lane as the "death lane" because once traffic is moving fast and heavy, you have no escape routes.  In an emergency, you can't go left, can't go right, all you can do is stand on the brakes and brace for impact from all directions.  You can be certain that if you suddenly brake in the middle lane, you will be rear-ended at extreme speeds, your only hope is to get clear of all lanes of travel.  If you don't believe me, watch some of the Youtube videos showing freeway accidents that continue to collect victims for many minutes after the initial impact as following traffic blindly plows into the wrecks.  By the time they realize something is wrong, there is simply nowhere to go.   Also, if you are in the middle lane traveling slower than the other traffic, you are forcing others to swerve left and right around you increasing the likelihood of an "incident".  I flat-out refuse the middle lane when I am on a motorcycle, in a car, more like a strong preference against.

JasonP

Quote from: ZCarFan on 11 May 2013, 08:42 AM
I would personally stay out of the middle lane though.  I think of the middle lane as the "death lane" because once traffic is moving fast and heavy, you have no escape routes. 

Well, that's a tough one. The road I travelled has a huge concrete barrier on the left, dividing the highway, so there is no escape that way. And the right lane is full of exits and merges, so traffic is constantly coming and going on that lane. I choose the middle lane because that is where the traffic is most constant, and for long distances it is the most stable. On the three-lane highway, where the speed limit is 75mph, the left lane ("fast lane") is where people try to go 90 and get away with it, and the right lane ("on/off lane") is where people are either exiting or merging. So even with all you are saying being true, I still think the middle lane is the overall safest place to be.

1979 300SD
Color: 623H "Light Ivory"
1979 300SD
Color: 861H "Silver Green Metallic"
1977 280 E
Color: 606G "Maple Yellow"
-------------------------------------------

Type17

#18
If traffic is heavy and moving at similar (slowish) speeds in all lanes, then the centre/center one is an ok place to be, but if things are moving quickly in some/all lanes, then it's best not to be in the centre lane for the reasons that ZCarFan suggests. If there's a concrete divider right beside the left lane, I'd choose the right lane (US slow lane), as there is the chance of using the shoulder if required.


Good luck with the commute JasonP, should be fine if you keep an eye on everything and improve the things you've already noticed.


PS: On a UK TV programme about the work of the Motorway Police, I heard them referring to those morons who drive too slowly in the centre lane, holding the whole place up, as member of the Centre Lane Owners Group (C.L.O.G.)  ;)
'76 350SE in Silver-Green

JasonP

Quote from: Type17 on 11 May 2013, 02:22 PM
PS: On a UK TV programme about the work of the Motorway Police, I heard them referring to those morons who drive too slowly in the centre lane, holding the whole place up, as member of the Centre Lane Owners Group (C.L.O.G.)  ;)

I'll keep that in mind.    :P

Lucky for me, I usually don't take the interstate. I take a one-lane for half the way, through country, and then a two-lane the rest of the way. My excursion on the interstate was just to go through a town on the way home. And I wasn't going THAT slow: between 70-75, where the speed limit was 75. But yeah, everyone around me was doing a minimum of 80.




1979 300SD
Color: 623H "Light Ivory"
1979 300SD
Color: 861H "Silver Green Metallic"
1977 280 E
Color: 606G "Maple Yellow"
-------------------------------------------

ZCarFan

I was not considering a barrier on the left.  I see your point.

I found my SDs were happier below 70.  The engine simply revs too much  above that.

JasonP

Quote from: ZCarFan on 12 May 2013, 06:33 AM
I found my SDs were happier below 70.  The engine simply revs too much  above that.

What do you consider too much? My rpms top out at around 3,500 when going 75-80mph.

I figure as long as I keep it below 4,000 for long periods, I should be fine, but that is just an uneducated opinion.
1979 300SD
Color: 623H "Light Ivory"
1979 300SD
Color: 861H "Silver Green Metallic"
1977 280 E
Color: 606G "Maple Yellow"
-------------------------------------------

JasonP


Well, I ran into one problem that needs fixing - the heat. I have my sunroof and windows down, but the heat from the dash gets overwhelming. On this long drive, I start to get drowzy, and tonite on the way home I was struggling to keep from dozing out. I hope it wasn't diesel fumes.

Anyway, I need to bypass my heating coils under the dash. Can anyone tell me how to do that? I want to use a bypass valve that can be switched back to "on," so this winter I can use it for Defrost.



1979 300SD
Color: 623H "Light Ivory"
1979 300SD
Color: 861H "Silver Green Metallic"
1977 280 E
Color: 606G "Maple Yellow"
-------------------------------------------

Casey

Quote from: WrightSounds on 30 April 2013, 10:12 PM
Quote from: ZCarFan on 30 April 2013, 09:44 PM
Nothing will seem exciting in life again after you lose your very first first tie-rod end.  ;)
That sentence alone makes my palms sweaty!



I've spent HOURS with this stupid fork tool and a big hammer and Powerblaster trying fruitlessly to loosen stuck tie rods.  Forget it, it's a terrible idea.  You'll just dent up your fork tool (and possibly your car) and get angry and throw it through a window anyways...

Just buy a ball joint separator tool like this one:



About $20, and you just get your handy ratchet and pop the tie rod right off with almost no effort at all.  In case your old tie rods aren't bad but you just need to remove them for some reason, this tool won't completely destroy them unlike the fork tool above which will.

Casey

Quote from: JasonP on 14 May 2013, 07:22 PM

Well, I ran into one problem that needs fixing - the heat. I have my sunroof and windows down, but the heat from the dash gets overwhelming. On this long drive, I start to get drowzy, and tonite on the way home I was struggling to keep from dozing out. I hope it wasn't diesel fumes.

Anyway, I need to bypass my heating coils under the dash. Can anyone tell me how to do that? I want to use a bypass valve that can be switched back to "on," so this winter I can use it for Defrost.

http://www.mercedessource.com/node/606

ZCarFan

Quote from: JasonP on 12 May 2013, 01:21 PM
Quote from: ZCarFan on 12 May 2013, 06:33 AM
I found my SDs were happier below 70.  The engine simply revs too much  above that.

What do you consider too much? My rpms top out at around 3,500 when going 75-80mph.

I figure as long as I keep it below 4,000 for long periods, I should be fine, but that is just an uneducated opinion.

4,000 RPMs?   Maybe a Honda D-Series but imho that's just abuse for a Diesel.  My Isuzu 2.2 Diesel was geared like that though.  1:1 high gear with 4.10s in the axles (yes 4x4) and 26 inch tall tires.  EEEK!  good thing it's 50 HP wouldn't get much above 65 mph.  With it's 4.09 first gear , 2.52 low range and 4.10 diff it did have enough gear to pull a house down at about 2 mph.  ;)

I'm sure the engine will survive at 80 mph, but mine always got very harsh and buzzy at that speed.  The vibration through the gas pedal and floor were not terrible, but quite noticeable and grainy.  Much more so than say a M110.  at about 55-60 they just purred along -- much better.

My Caprice and Mustang both are running less than 2,500 at 80.  The Buick LeSabre I had with a 3800 was about the same.  It turned in about 30 MPG at 70-75 too as proof of concept.  Same with the two A-Body GM wagons (both 60 deg v-6s) we once had.  All of those are gas engines that are happy at revs that would be likely fatal for a OM617 but still geared higher nonetheless.

I am used to a very different gearing philosophy, where low revs are coupled with low rpm torque to give good quiet service.  The trans can always downshift when you need more power, no need to keep it in the torque peak all the time if you are just cruising along at a relatively steady speed.  Then again, the 300SD was born into a time when 55 mph was the national speed limit in the US, so maybe in that context the gearing is pretty good for the application at the time.  Still, this means 55-60 is good, 75-80 may be at the high end of advisable.


ZCarFan

btw... I do not intend to be negative about the car or discourage you.  I do think it is worth mentioning such things, particularly how it's done elsewhere, as I believe it is important to show that there is more than one way to get a job done.

JasonP

Quote from: ZCarFan on 15 May 2013, 06:12 PM
btw... I do not intend to be negative about the car or discourage you.  I do think it is worth mentioning such things, particularly how it's done elsewhere, as I believe it is important to show that there is more than one way to get a job done.

I don't see any negative. That's why I post - to get all kinds of opinions and views. Thanks!  8)
1979 300SD
Color: 623H "Light Ivory"
1979 300SD
Color: 861H "Silver Green Metallic"
1977 280 E
Color: 606G "Maple Yellow"
-------------------------------------------

JasonP

Quote from: Casey on 15 May 2013, 12:10 PM
Quote from: JasonP on 14 May 2013, 07:22 PM

Well, I ran into one problem that needs fixing - the heat. I have my sunroof and windows down, but the heat from the dash gets overwhelming. On this long drive, I start to get drowzy, and tonite on the way home I was struggling to keep from dozing out. I hope it wasn't diesel fumes.

Anyway, I need to bypass my heating coils under the dash. Can anyone tell me how to do that? I want to use a bypass valve that can be switched back to "on," so this winter I can use it for Defrost.

http://www.mercedessource.com/node/606


Thanks, Casey. But that seems pretty pricey! I was thinking I could just go to the hardware store and rig something up. I have no A/C, so I thought I could just bypass the heat coils in the dash, and that would be that. But maybe not....

Since we are on the subject, I need to take care of this climate control this year. The commute is too long to put up with it. Last summer I was fine, because it was only a 20-minute drive, and I could wear shorts and a t-shirt to work. But now it is just too much.

I need to seal my doors and windows, replace the rear windshield (already have it), and install an ad-hoc A/C system. I need a cabin I can be comfortable in, in all weather. I still want to restore the original A/C system, as I have all the parts, and then some. But I need this done now. Function comes first. So my goals is to have all of this taken care of in the next few months. Hopefully I can do it.

1979 300SD
Color: 623H "Light Ivory"
1979 300SD
Color: 861H "Silver Green Metallic"
1977 280 E
Color: 606G "Maple Yellow"
-------------------------------------------

ZCarFan

Quote from: JasonP on 15 May 2013, 07:10 PM
Quote from: Casey on 15 May 2013, 12:10 PM
Quote from: JasonP on 14 May 2013, 07:22 PM

Well, I ran into one problem that needs fixing - the heat. I have my sunroof and windows down, but the heat from the dash gets overwhelming. On this long drive, I start to get drowzy, and tonite on the way home I was struggling to keep from dozing out. I hope it wasn't diesel fumes.

Anyway, I need to bypass my heating coils under the dash. Can anyone tell me how to do that? I want to use a bypass valve that can be switched back to "on," so this winter I can use it for Defrost.

http://www.mercedessource.com/node/606


Thanks, Casey. But that seems pretty pricey! I was thinking I could just go to the hardware store and rig something up. I have no A/C, so I thought I could just bypass the heat coils in the dash, and that would be that. But maybe not....

Since we are on the subject, I need to take care of this climate control this year. The commute is too long to put up with it. Last summer I was fine, because it was only a 20-minute drive, and I could wear shorts and a t-shirt to work. But now it is just too much.

I need to seal my doors and windows, replace the rear windshield (already have it), and install an ad-hoc A/C system. I need a cabin I can be comfortable in, in all weather. I still want to restore the original A/C system, as I have all the parts, and then some. But I need this done now. Function comes first. So my goals is to have all of this taken care of in the next few months. Hopefully I can do it.

Cheapest alternative is a crappy sent of needle-nose pliers.  Just clamp off the hose.  Yes, it works, and no, it's not a good idea.