Just replaced strip fuse and it cracked in half when I attempted to start the car! I tested voltage on battery and it is 12.54. Tested voltage inside glow plug relay - it is around 12.47 volts tested voltage on powered side of strip fuse and get 12.47 obvoiusly I get zero on other side since it is cracked. Also tested resistance with multimeter turned on and set at 200ohm - it reads 0.6 by itself (meter won't zero out) Tested #1 glow plug relay wire and got 0L ohms (what does 0L mean? - i assume that means zero), Tested #2 and got 0.9 ohm need 0.6 deduction thus 0.3 Tested #3 glow plug relay wire and got 1 ohm - 0.6 = 0.4 ohms Tested #4 and got 0.9 ohm reading - 0.6 = 0.3 ohm and tested #5 and got 1.0 ohm - 0.6 = 0.4 ohms Need to get a strip fuse from dealer - I think they are 30 amp (let me know if that is correct) Okay now what does all this mean? Is #1 my problem area? Also when I go to start it , car cranks fine but glow plug light in the instrument cluster does not come on. Getting late will check glow plugs tomorrow.

OL on your meter probably indicates an open circuit which would mean you need to replace that glow plug. The other resistance measurements seem reasonable and since the car cranks fine it's likely that the rest of the plugs are good.

The strip fuse opening doesn't necessarily indicate an over current condition as these things will often fail after years of temperature cycling. Is the fuse you removed stamped 30A? All the 617 glow relay fuses I've ever seen are 80. There are applications for the 30A and 50A strip fuses but not in the GP circuit.

Not sure what the dealer will charge but those strip fuses are available from several sources (including this site) for less than a buck each.

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Joe

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1980 300SD - 495k miles - 'The Ambassador'
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Former Family Members
95 C280
73 280SEL
90 300D
87 300SDL (X2)
86 560SEL
84 300D
80 300SD

The Strip Fuse is flat when you get it but it is supposed to have an dip in it to allow for heat expansion.
Slide the Fuse onto the Relay and turn the Screws down enouh so they barely touch the Fuse. Put your Finger in the middle of the Fuse and push down; bending the fuse down.
Tighten the screws and release your Finger from the Fuse.

Below is what I did to my cracked Fuse while I waited until a new one came.
The Clip sticks straigh up from the relay and bridges the crack. I figured that way the Fuse could still offer protection and burn if there was a short.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

Will pull fuse off tomorrow an double check amps. Headed to dealer to get bosch glow plug and a strip fuse and an extra bulb for inst cluster. So where is #1 glow plug located on an 84 300SD? near firewall or near grille? I am hoping you say near grille - cause the other side is near oil filter housing which looks real tight.

... the OL, means it's an open circuit, so yes, that fuse is blown.
the -5 ohm reading, uh. I think you need a better meter. it's likely you have a shorted fuse if the strip fuse was an 80, and if failed instantly. follow all plug wires, and see if there are shorts to the motor somewhere. common is the wire where it connects to the plug itself, turns around and hits the head.
I've also seen where the wire insulation breaks off, and makes contact with an injector line or similar.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

vstech - I do not have any -5 readings; but I like the advice in case there was a short - will help me in the future. Also my son informed me the order of the glow plugs was on the block - maybe there is hope for the new generation! So looks like #1 in nearest the grille

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72 350SL, 73 450SL, 82 300TD,84 300SD, 85 300D

This could be as simple as a bad bulb. Also check to make sure the metal tab on the bulb holder is making contact with the socket.

__________________
Joe

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1980 300SD - 495k miles - 'The Ambassador'
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Former Family Members
95 C280
73 280SEL
90 300D
87 300SDL (X2)
86 560SEL
84 300D
80 300SD

Got the OEM 80 amp strip fuse today - also checked #1 glow plug just to make sure it has resistance (since it was the one I replaced) - it had 0.5 ohms after zero adjustment - so I got in and turned key and glow plug light came on fairly quickly (it is 68 degrees here today) and car fired right up. Since it has sat for awhile, I turned it off. Want to check and make sure fuel is ok (no algae,etc,.) ****Hey members - thanks for all the help! ***

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72 350SL, 73 450SL, 82 300TD,84 300SD, 85 300D

Glad you got it working!

Quick question, when was the last time you reamed the glow plug sockets? My 617 originally blew the strip fuse because of the carbon buildup.

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1982 300GD Carmine Red (DB3535) Cabriolet Parting Out
1990 300SEL Smoke Silver (Parting out)
1991 350SDL Blackberry Metallic (481)

"The thing is Bob, its not that I'm lazy...its that I just don't care."

I have never ream the glow plug sockets - wil keep that in mind if it fails again - thx

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72 350SL, 73 450SL, 82 300TD,84 300SD, 85 300D