123 Warm Up Time - PeachParts Mercedes-Benz Forum

remotemark · #1 10-31-2008, 08:54 AM

This seems like a stupid question, but I don't know the answer to it. I usually let my 300D warm up for about a minute and a half after I start it on these getting colder mornings. Is that a waste of time or should I be letting it warm up longer?

H-townbenzoboy · #2 10-31-2008, 10:13 AM

You should just wait for the oil pressure gauge to peg the max mark and then drive. No need for a warm up.

bbboomer · #3 10-31-2008, 10:26 AM

Don't know about just waiting long enough for oil pressure gauge to peg then driving. I really think a warmup is necessary.
I generally wait a couple minutes then drive gingerly till the engine temp reaches normal. I live a couple miles from any main road so it allows for warm up without working the engine hard.

remotemark · #4 10-31-2008, 05:40 PM

Well, it hits max oil pressure pretty much right away.

bbboomer · #5 10-31-2008, 06:03 PM

You're right and that is the problem. Unless your engine is junk the oil pressure will be max as soon as you start if cold. That doesn't mean good to drive. Let it warm a bit before you drive, your engine will appreciate it!

bgkast · #6 10-31-2008, 06:38 PM

The problem is these engines make very little heat at idle. I just start it up and drive away. Just don't beat on it until the temp comes up.

barry123400 · #7 10-31-2008, 07:10 PM

You might consider just using the block heater for about 1/2 hour before starting up and driving away. Increase time as it gets colder. Just remember if you are leaving at say nine to plug it in earlier. Or put it on a timer if you consistantly leave at the same time.

It has always been said that the cold start of an engine has the greatest wear component. Fokelore or otherwise. Your car heater will come up to usable temperature earlier as well. We are going to need them soon enough unfortunatly.

bgkast · #8 10-31-2008, 07:31 PM

It doesn't get much below freezing here.

Jeremy5848 · #9 11-01-2008, 01:46 AM

Another option is to modify the pre-glow system to provide some afterglow, that is, allow the glow plugs to remain energized for 30 seconds or so after the engine starts. You can either modify your existing system or substitute a later model pre-glow relay. The engine will smooth out faster with some afterglow.

Regardless of this, it's definitely wise to not romp on the engine until the coolant has at least come off of the peg or better yet, reached full operating temperature. I have a 1/4 mile gravel drive to reach the highway; with 30 seconds or so of warmup before moving and a minute or two to reach the highway, my engine is ready to perform and usually ready to start providing a little heat in the cabin. (Granted, if I still lived in northern Wisconsin, it might take a little longer.)

compress ignite · #10 11-01-2008, 02:41 AM

Using the modern wonder of the EDIT Function I've altered my scenario.

'Block heater plugged in unless Ambient Air Temps above 80 F.

(Wacko Mental Computations:'Will a single dedicated Auxiliary Battery,Solar Charged,provide enough time for a partial warm-up
"Away from Home"? 'Given losses to Inversion.)

2 minute "Warm Up" before driving off.
Then drive Gently until it's at Operating Temps.

After you've "Asked it for some serious RPMs"...
A 2 - 3 minute "cool-down" @ Idle will prolong the Turbocharger's lifespan.

remotemark · #11 11-02-2008, 07:26 AM

Well, since I wind up on the highway pretty fast on my morning commute, I think I'll just sit and listen to the radio for a couple minutes before I head out. Now that Sirius has both an AC/DC channel and a Led Zeppelin channel, I'll find something to listen to.

Brian Carlton · #12 11-02-2008, 08:06 AM

Quote:

Originally Posted by remotemark

Well, since I wind up on the highway pretty fast on my morning commute, I think I'll just sit and listen to the radio for a couple minutes before I head out. Now that Sirius has both an AC/DC channel and a Led Zeppelin channel, I'll find something to listen to.

Naturally, it depends on the highway and whether you can pull it off, but running the engine at 2000 rpm (about 43 mph) is perfect for a rapid warmup (about 5 minutes unless it's very cold).

You can sit in your driveway for five minutes and the needle will still be on the peg. What did you accomplish?

In the colder temperatures, I don't let the either the 603 or the 617 to go above 2100 until the engines reach 160F. Even at that point, they have not fully warmed their oil, so, an argument could be made to extend the low speed operation.

Hatterasguy · #13 11-02-2008, 01:27 PM

With a turbo charged engine I stay off boost until the oil is warm. So that means no more than 2k on these engines. Turbo's spin really fast, and cold oil doesn't move so fast.

Back when I drove the SD in the winter I would usualy fire it up and than scrap the windows. These engines take forever to show any heat at idle. They hold a lot of oil, coolant, and have beefy blocks, so it takes some time to warm that mass up.

Just get in and drive off, cold idleing just creates soot and carbon. The fuel really isn't burning well.

MBdieselFreak · #14 11-02-2008, 01:34 PM

Quote:

Originally Posted by remotemark

This seems like a stupid question, but I don't know the answer to it. I usually let my 300D warm up for about a minute and a half after I start it on these getting colder mornings. Is that a waste of time or should I be letting it warm up longer?

My token on this is that you need to let it warm up to minimum operating temps. witch is 40and then at 80 you can do what you want!
I never drive my cars without heating up the engine nicely!

A COLD ENGINE WILL WORN 100TIMES FASTER THEN A WARMED UP ENGINE!

Just think about all the cold metals, oil's, fluid's and parts from your engine struggling to heat up while your driving it, but then when the engine is warm its ready to work hard and your engine/trans will thank you.

MBdieselFreak · #15 11-02-2008, 01:37 PM

Before i leave i always plug my block heater (during cold weather) and i start the car and let it idle for 10 mins minimum.