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1985 300D Turbodiese
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Discussion Starter #1
A friend of mine suggested that my '85 300D Turbodiesel might start easier on cold mornings if I kept the engine block heater plugged in over night. He also said that he believes this model came equipped with said heater. True? If so, where do I find the receptacle?
 

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1983 240D
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3 Posts
If you have one, it will be around the radiator. It should protude from under the gri...

If you have one, it will be around the radiator. It should protude from under the grill area. It looks just like the cord a house lamp would have.
If you have one you cant miss it. If not, I dont think they are expensive.
 

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1991 300E
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117 Posts
The 85 shouldn't need a block heater unless your trying to start it in sub 0degF. Now i...

The 85 shouldn't need a block heater unless your trying to start it in sub 0degF. Now if you had a 79 or earlier you would need one down below about 25F. Everything after 80 had more advanced glowplugs. Before I started trying to chase a block heater (not the easiest thing to find) I'd look at getting new glow plugs. It could be that yours are old and tired or that one burned out, one cold cylinder would make it hard to start. Good Luck!
-M-
 

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00 S500,99 4wgn,87TD
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Ok - first- an 85 should not need a block heater. Of course it always helps,and if you hav...

Ok - first- an 85 should not need a block heater. Of course it always helps,and if you have one,(heater is located just above starter in block),do NOT leave it in all night. This will not only consume lots of electricity,(it's 400 watts) but will cause premature wear of the heater. A heater should last many years. The block heater only needs 2.5 to 3 hours to warm up the block. Purchase an appliance timer, capable of switching a 15 amp load, and a good heavy duty extension cord. Do not get one thats too long. It should be just the right length. Set the timer for a few hours before you plan to leave the house. Second- the most overlooked thing to do to your 1985 and down diesel, 240's and 300's, are the valves. They MUST be done prior to the winter months. The design of the valve train on these engines are different than all other engines. As temps outside decrease, the clearances decrease. If the valve clearances are too tight, they get tighter as it gets colder. This means that the valves do not close meaning super low to no compression. As we know, diesels require compression. At least 350 psi. Even if one cylinder is too tight, it will be hard to start. 5 cylinders need 5 to start , 4's need all 4. I hope this makes sense to all. So remember, always adjust your valves once a year, and do them COLD,first thing in the morning.(it's the least you can do for the engine that gave you no trouble the rest of the year). Make sure the 80 or 50 amp fuse is good. You should make it a habit of changing it when the valves are adjusted. Check the glow plugs for proper operation. If one is bad, change all. You don't want to do them when it's cold,and you only want to open the hood this winter to check the oil. A properly adjusted, good glow plug ,good fueled car will start when it's cold. PS.. the number ONE cause of a burned valve is one thats out of adjustment.....
 

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Sage advice by BenzDoc.

However, you might want to glow the car several times prior t...


Sage advice by BenzDoc.

However, you might want to glow the car several times prior to cranking. This helps cycle the heat in the prechambers.

The '85 will definitely have trouble starting below 32 degrees F. But you should always be able to get it started above 0 as long as the compression is good.

There is a trick to starting these cars, and you can't be afraid of that starter. Give it 3/4 maximum throttle and crank it for up to 45 secs to see if the engine catches. When it does, "RRRRRRR", "Shake"...."Shake".."Shake""Shake""Sha,Sh,Sh,Sh,(slowly release pedal)
Vrroom!, Klatta, Klatta, Klatta!"[:D] She's alive![:D]
 

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1985 300D Turbodiese
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9 Posts
Discussion Starter #7
update

I had all five glow plugs replaced yesterday. It was cold this morning, but she started on the first crank. I was so excited I got a speeding ticket.
[:0]
 

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'02 WRX Blue
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41 Posts
You guys have me scared.

All last winter I left my car plugged in over night. Probably from 4pm - 6am most days.

Now it just got real cold here (10F) and I forgot to plug in my car...no startum. Now 3 hours late for work the car has been plugged in and I just got it running.

Except for the big draw, what am I really damaging? Shouldn't the heaters hold at a temp, or does it just heat until things glow?

Anyway, I also have to replace my glow plugs again, that I replaced Spring '02. The OEM replacement are not firing I'm down a cylinder on start.

Shane Kullman
'82 300D Sliver
 

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'83 300SD Turbo
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I find that mine started easier last week on those 30 degree mornings than it does on 40 +...

I find that mine started easier last week on those 30 degree mornings than it does on 40 + degree days. I cycle the key 2 times for the glow plugs and it starts right up.
 

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00 S500,99 4wgn,87TD
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579 Posts
Re: I find that mine started easier last week on those 30 degree mornings than it does on

I find that mine started easier last week on those 30 degree mornings than it does on 40 + degree days. I cycle the key 2 times for the glow plugs and it starts right up.
There is no reason to cycle twice. The glow plug relay stays on for thirty seconds (fast plugs,pencil type) after the key is turned to position 2. When the relay recieves a signal from 50, which is start position, relay shuts down. So after the light goes out, which by the way is timed by the engine compartment temprature, which can range from 4 to 10 seconds, just continue to count 10 extra seconds, then crank.........Ps. save the life of your glow plugs by not using them when the engine is fully warmed up. When you turn the key and the engine is at or above 80c , just crank it up!
 

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'02 WRX Blue
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So what you're saying is

That it doesn't matter that my car is plugged in over night.

And if my glowplugs take 30 seconds to warm, I should replace them.

Where can I get the super duper fast glow kind? Brandnames and models would be helpful.

THanks.
Shane Kullman
'82 300D Silver
 

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00 S500,99 4wgn,87TD
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579 Posts
Re: So what you're saying is

That it doesn't matter that my car is plugged in over night.

And if my glowplugs take 30 seconds to warm, I should replace them.

Where can I get the super duper fast glow kind? Brandnames and models would be helpful.

THanks.
Shane Kullman
'82 300D Silver
Shane, There is NO need for overnight heating. Depending on outside temp.,3 to 4 hours are all that is required.If your valves are adjusted CORRECTLY, and your glow plugs are functioning, it will start without plugging it in in temps above 20*f. If you know its going to be below zero all night, use a timer on the heater. That 400 watt heater @ 0*f,will temp up the block to aprox. 70*f in 3 hrs. Just rest your hand on the valve cover after 3 hrs. and feel for yourself. As for the glow plugs, all I said was that the relay stays engaged even after the light goes out. Rather than cycle twice, just count out 10 more seconds after the light goes out then start. Thats all. Your 82 has the fast plugs already. good luck........
 
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