Temperatures in low teens - do I need to plug this thing in? - PeachParts Mercedes-Benz Forum

deniss · #1 01-25-2007, 07:11 PM

There should be about 13F outside tomorrow morning, when I will need to start my car ('84 300SD, OM617)...

So far, low 20s F were the lowest temps I tried starting in, and the engine has been catching pretty fast, with proper pre-glow - no hiccups or any need to throttle with the pedal.

My question is, can I get away with a couple 30-sec pre-glow cycles at 13F before trying to start, or should I plug the electrical cord on the engine into the wall? If the advice is the latter, can someone give me an idea as to how long I need to have the thing plugged in before attempting to start?

waybomb · #2 01-25-2007, 07:13 PM

If you have to be somewhere, then plug it in! It doesn't cost hardly anything to run the block heater.

Jeremy5848 · #3 01-25-2007, 07:25 PM

You can leave it on all night, use a timer, or get up early and give it two to four hours. It won't hurt anything, won't cost but a few pennies, and will help the engine start more easily. Less wear and tear on the engine is always good.

If you have a trickle charger, put it on the battery overnight. A fully charged battery is always a help in starting an engine. The waste heat from the charging process also keeps the battery a little warmer so it works better. (Cold batteries lose some of their capacity.)

deniss · #4 01-25-2007, 07:36 PM

Quote:

Originally Posted by Jeremy5848

You can leave it on all night, use a timer, or get up early and give it two to four hours.

I'd leave it on all night - not worried about the electricity cost for this. But I live in an apartment complex, so I'll be running an extension cord from my second-floor balcony that has an oudoor wall plug... I'm a little uneasy leaving it overnight, in case someone decided to be curious and do me some sort of "favor"... I guess I'll get up early and plug it in a couple of hours before leaving.

F18 · #5 01-25-2007, 08:53 PM

The block heater draws about as much current as a 50 watt light bulb......so a weeks worth of use might cost you the equivalent of a Starbucks Latte Grande'. Still much cheaper than a tow......
When in dought ..plug in!

Knightrider966 · #6 01-25-2007, 08:59 PM

Quote:

Originally Posted by deniss

There should be about 13F outside tomorrow morning, when I will need to start my car ('84 300SD, OM617)...

So far, low 20s F were the lowest temps I tried starting in, and the engine has been catching pretty fast, with proper pre-glow - no hiccups or any need to throttle with the pedal.

My question is, can I get away with a couple 30-sec pre-glow cycles at 13F before trying to start, or should I plug the electrical cord on the engine into the wall? If the advice is the latter, can someone give me an idea as to how long I need to have the thing plugged in before attempting to start?

Yes, Plug it in! It won't hurt anything. It should be plugged in for about 2 hours. but leaving it plugged in all night won't hurt either. the electrical cost is minimal.

captainmonk · #7 01-25-2007, 09:35 PM

my car starts at -3 in new hampshire without plug in but they are all different and i have new battery and glow plugs
will be down workin in point pleasant nj next couple of months where are you?

Hatterasguy · #8 01-25-2007, 09:44 PM

Depends on the car, my SD will get at least 6 hours of block heater time if I want it to start tomarrow.

The SDL on the other hand would require me to wait until the GP light goes off then a quick turn of the key.

Depends on the condition.

babymog · #9 01-25-2007, 09:55 PM

If you can plug it in, then why not.

Consider that:

Each compression cycle without combustion is un-burned fuel to contaminate the oil or dry the cylinder walls before the next stroke.

Harder cranking is higher current, faster brush/commutator wear in the starter.

Running rough/uneven is also washing the cylinder walls down with fuel and creating more soot for the oil.

And most important: plugging it in will give faster heat from your heater.

Even if it doesn't **need** to be plugged in, it certainly is easier on the engine, I plug mine in below about 45F just because I like those summertime instant starts (and because there's a plug in the garage for it).

#10 01-25-2007, 10:25 PM

My Mercs are parked in a garage, but I still like to at least plug the 617engines in if the temperature is below 35F. The only 'draw back' to doing this is that a weak battery could be hiding. Allow me to explain. I have been driving my 1981 300D daily for a while as the 1985 is getting repainted. My 1981 always starts quick in the morning at home and when I leave work in the late afternoon. A week ago I traded my car for a friends truck to tow my parts car home that I had purchased. The next morning I took the truck back and went to leave in my car. My friend does not have a garage so that car was outside. That morning was in the high teens and windy. I cycled the glow plugs and turned the keys. The engine did not start immediately, but I held on cranking for a few seconds excepting it to start. Well, suddenly I went from what seemed to be full cracking speed dropped down to barely turning the engine. All is OK now, but it is time to replace that battery. By the way...trying to jump start a diesel from a small non-diesel battery is a joke. My friend had a large engine starter. That took care of getting started in a flash. I am getting me one of those.

My S-10 came with a factory block heater. I plug it in during the winter as well just because I can and it allows for quicker warm up. I have also installed heaters in other gassers that I have had. If the temperature gets below 10F an engine block heater is a nice thing o have, especially if you vehicle is parked outside.

Jeremy5848 · #11 01-25-2007, 10:45 PM

Block heaters draw 400 Watts, not 50. Radiator hose heaters (like the one Diesel Giant sells) for those who can't get the block plug out, draw 600 Watts. Either way, it's a lot cheaper than having to call a tow truck to get you started.

olsaltybastard · #12 01-26-2007, 01:18 AM

Quote:

Originally Posted by Jeremy5848

Block heaters draw 400 Watts, not 50. Radiator hose heaters (like the one Diesel Giant sells) for those who can't get the block plug out, draw 600 Watts. Either way, it's a lot cheaper than having to call a tow truck to get you started.

I was about to correct a lot of folks. I checked mine with a device used to test medical equipment and came up with 2.9 amps of current draw. I also found out how quickly the element heats up in your hand (yes, I am a trained professional!!)

pawoSD · #13 01-26-2007, 01:30 AM

Quote:

Originally Posted by olsaltybastard

I was about to correct a lot of folks. I checked mine with a device used to test medical equipment and came up with 2.9 amps of current draw. I also found out how quickly the element heats up in your hand (yes, I am a trained professional!!)

Pretty sure you're not supposed to turn it on in the open air...

"Risk of destroying element" is what I remember from the instructions that came with one I had.

Its going to be TWO degrees here tomorrow morning, and I am not worried...its not plugged in, I know a good 10-12 second glow and 5-6 cranks and it will be running fine.

It just started after a 10 second glow and 4 cranks here tonight about half an hour ago, and it was only 11F.

Our new 300D seems to be more of a complainer about the temps...I'm going to run it tomorrow to see how it does....if it starts that is.

pizzachef · #14 01-26-2007, 08:09 AM

The cord to my block heater is not plugged into anything. I followed the cord, and the end that should be in the heater is dangling back there somewhere. I looked as best I could from above and squeezed my head underneath and looked, but couldn't see the heater in the side of the block. Is it below the exhaust manifold somewhere? Do I need to put the car on stands to get to it or can I reach it from above?

And just in case its unplugged for a reason

does the radiator hose heater from diesel giant heat all of the coolant or just what's in the radiator? I guess I could look at my own car and find out...but its cold outside

Thanks,
-Geoff

SwampYankee · #15 01-26-2007, 08:18 AM

Mine didn't like it at 1*F this morning, I decided I'd let it sleep in, but it has started easily until this morning in the teens and 20's. I think it's time for a new battery though.