Curvy wire that connects glow plugs

[bajo]

Hi. I have a 1981 300D. Can anyone tell me what is the curvy wire (thick wire that resembles an upside-down "W") that seems to connect the glow plugs? I need one or two replacement parts for this, so if you could tell me the official name or part #, I appreciate it. Is it some type of resistor?

bajo

[kerry]

Not worth buying the part. Pencil plugs are far superior to loop plugs. Just buy the retrofit pencil plugs, throw away those heavy wires and move forward with better starts.

Those are the resistor wires. I agree with Kerry, retrofit pencil glowplugs as they are FAR superior to the loop style.

[bajo]

Thank you gents. Is this an example of what you are talking about?

http://www.**************.com/node/4024

or (better yet?)

http://www.dieselgiant.com/diesel_parts_for_sale.htm#5%20cylinder%20Glow%20Plug%20Retrofit%20Kit%20for%20the%20Older%20Loop%20S tyle%20Plugs

[kerry]

Those are pencil plugs but not the ones you need. The loop plug threads are larger in diameter than the standard pencil plug threads. So you need a special pencil style plug with threads as large as the loop style plugs. Someone recently posted the correct part number on a thread.

[bajo]

Is that second url (above) closer to the right thing?

bajo

[greasybenz]

Here is the correct kit for your car:

http://catalog.worldpac.com/mercedesshop/sophio/quote.jsp?header=header.jsp&footer=&product=0250201955&partner=mercedesshop&baseurl=http://catalog.peachparts.com/&clientid=catalog.mercedesshop&cookieid=2800UIN0N28K01LLYY

part # 0250201955

[kerry]

Yes, that's it although you don't need the whole kit. You can just buy 4 plugs if you make the jumper wires to go from plug to plug. I used the existing relay on my 77 300d when I did the switch over 5 years ago and it's still working fine.

[JimFreeh]

Originally Posted by bajo

Hi. I have a 1981 300D. Can anyone tell me what is the curvy wire (thick wire that resembles an upside-down "W") that seems to connect the glow plugs? I need one or two replacement parts for this, so if you could tell me the official name or part #, I appreciate it. Is it some type of resistor?

bajo

A 1981 300D should already have the new style glow plugs......Wasn't the changeover in mid 79?

Jim

[kerry]

Originally Posted by JimFreeh

A 1981 300D should already have the new style glow plugs......Wasn't the changeover in mid 79?

Jim

I'm under the impression that the switch occurred when going from NA to Turbo. And 81 300d should be an NA. Perhaps I am mistaken in this understanding.

[P.E.Haiges]

baja,

The series (loop) plugs are ~1.5 volts each. The resistor wires and the GP indicator in the dash drop the 12 volt battery voltage to about 6 volts for the GP. What a waste of energy. Maybe the pencil tip GP were not available earlier, but 12 volt loop GP could have been made to eliminate the resistors.

I wonder if these series plugs were left over from 6 volt systems or used in an 8 cylinder 12 volt system.

It sure took MB a long time to update to the paraller (pencil) GP. I can't believe MB changed some MB engines to parallel plugs and not others.

P E H

[nscarr]

Originally Posted by kerry

I'm under the impression that the switch occurred when going from NA to Turbo. And 81 300d should be an NA. Perhaps I am mistaken in this understanding.

my wife's 1980 wagon has the pencils, and my 1980 sedan had the loops--replaced with those "large diameter thread" pencils and works fine, but i already had the updated relay. neither of the cars is a turbo; i thought 300d were turbo from 81-85 (?), and with pencil plugs? maybe it's a donor NA engine?

[bajo]

It's an '81 body but a '79 engine. Left out that little detail!

bajo

[thesst]

My 79 300SD came with the new-style pencil plugs (and not the "retrofit" style). I guess yours must be from early '79. Lucky you.

[kerry]

Originally Posted by thesst

My 79 300SD came with the new-style pencil plugs (and not the "retrofit" style). I guess yours must be from early '79. Lucky you.

79 SD's are turbo. 79 D's are NA. SD's were the first to get the turbo's (all SD's had the turbo) followed by the wagons (( think) and then the sedans in 81 or 82 (I think).