Om617 loop spiral to pencil
 

Hi, I want to convert loop spiral to pencils as today I want to move my 300D and had a hard start (three cycles to start).

I want to keep the time of the original relay and will use a second relay to put more amps through the plugs.

Is this diagram safe to use ?

https://imagizer.imageshack.com/v2/8...923/YdW8gl.png

Not possible to convert to pencil plugs and pencil relay? I think even the glow plug relay is a separate section from the main harness.

Sixto
98 E320s sedan and wagon
02 C320 wagon

The point of the original Mercedes system is partly to protect the plugs - there's a chance you'll burn them out if you start using them for long than intended.

If you are having a rough time getting the engine started have a look at the condition of the engine oil (fresh oil always helps), the health of the starter (a rebuilt starter spins faster) and if necessary consider fitting a block heater.

I feel compelled to add that In most (weather) situations in the Netherlands I've never had trouble starting my OM617 (or any other vehicle)

All done except glow spirals and injectors.

My '78 uses the stock setup with no problems except the glow timer doesn't shut off until you engage the starter so I wouldn't worry about an extra relay myself.

PS They're a loop not a spiral and these same questions seem to come up every couple weeks so a search would help you out :)

I doubt the pencil relays aren’t going to draw 120a, and your relay coil isn’t going to draw 80a. You need to install an appropriate fuse on the 30/87 run for this to even be safe. It doesn’t seem that your added relay has any purpose.

Cold Weather Starting Drill
 

? When was the last time you adjusted the valves ? .

This is the # 1 cause of hard Winter starting .

Been measured (only one adjusted)

these pencils draw 15A each instead of 10A so relay cant handle it I guess.

If this is for a w115 300D the only issue I see is with the thermo time switch not being in the loop somewhere to tell you when the plugs are hot enough. It acts as the ground for the loop glow plugs in the original system.



Perhaps it could be connected to terminal 85 in your diagram? There are two connections on the switch, one for the original plugs and the other is for the gp light in the dash. I would connect the one for the plugs to 85

the original thermoswitch on the block will be used (attached to the old relay)

So you need a 100a fusable link in place of the 150. And your 85/86 coil draws maybe 1a, so a small fuse there. Where did you find a 120a relay?

The standard for years has been to use the old ford starter relay that bolts to the side fender apron. Both cheap and reasonably reliable. Still available easily as well but this may pass with time.

Did I forget to mention cheap and normally deals with the full current in a ford starter? Actually I have never heard of a reasonable alternative to them.

Ford starter solenoid would have been my choice. But he’s showing something with DIN terminal designations, thus the question.

Glow Plug Control
 

Jeeze ;

Don't screw around with barnyard starter relay bodge repairs ~ fix the darn thing properly, there's myriad posts on how to do this using cheap junkyard parts .

https://imagizer.imageshack.com/v2/8...923/TDpQlR.jpg

I want to keep the original relay to use it as a timer.

https://imagizer.imageshack.com/v2/8...921/WSHixt.png

I never had any issues with my original rely powering the pencils...
Just ran the #8 feed wire to each pencil and it worked fine for the 3 years I drove the car...

I did change the 50a fuse to an 80...

My original relay says 60A max. is that even enough for the quick glow plugs? These new plugs come from a G class....

well my glow light doesnt work after replacing the pencil style?

It glows really good compared to the old system.

bulb has been checked.

Anyone know how to rewire?

https://imagizer.imageshack.com/v2/8...921/q50bDy.jpg

https://imagizer.imageshack.com/v2/8...921/iS9wuM.jpg

A more clear picture:

https://i.ebayimg.com/00/s/OTk5WDc0O...FbY1RN/$_1.JPG

I guess I need to wire G and La together?

G and La will work but, lamp will go out after cut out will find timer relay.

Sorry for the late response but it could be that all you need to do is adjust the valves and use lighter weight oil.

adjusted, 5w40 is light. Starts fine now. 10 secs wait and go.

When I tested the Pencil Glow Plugs on my 84 300D with an dash board type Amp Meter that had to be connected into the circuit when I first applied the current it pegged the gauge out at 60 amps which is as high as the gauge would go then as the tip of the Glow Plug to hot the amperage fell to about 16 amps and held steady.

If you are going to use the Glow Plugs in the attached picture what you want to do is entirely safe.

Look like you plan to use the original Relay to activate a Ford type Starter Solenoid.

I am not sure if the original relay is going to function properly but I can't see you damaging anything. If the original Glow Plug Relay dose not work you can use a push button switch. That is what I did no my Volvo Diesel.

I don't believe the Starter Solenoid activation circuit need an 80 amp Fuse. On the activation circuit on the Volvo Diesel I used 16 gauge wire with no issues.

You won't need a 150 amp fuse because you it should use a 80 amp fuse.

A wiring diagram similar to what I used.

I don't need this, I am using external relay and timer. But, still thanks for the idea.

Well other people with questions will likely read this post at sometime and it could be helpful to them.

Here is a sample of mine conversion.

https://imagizer.imageshack.com/v2/8...922/MODoCP.jpg

https://imagizer.imageshack.com/v2/8...922/5tKiiF.jpg

https://imagizer.imageshack.com/v2/8...924/9CMsge.jpg

https://imagizer.imageshack.com/v2/8...923/WnDBFb.jpg

https://imagizer.imageshack.com/v2/8...921/q50bDy.jpg

https://imagizer.imageshack.com/v2/8...922/w2NSWh.jpg

https://imagizer.imageshack.com/v2/8...924/GIBldL.jpg

https://imagizer.imageshack.com/v2/8...924/0llgpV.jpg

Diagram voor aansluiten:

https://imagizer.imageshack.com/v2/8...921/WSHixt.png

https://imagizer.imageshack.com/v2/8...924/adcgPV.jpg

Glow Plug Variables
 

I'd get rid of that 120 ampere fuse straightaway .

I'd also solder every one of those crimp connections as they're going to get resistance over time......

All these diagrams are great ! they allow DIY'ers to choose the path they prefer and then do it correctly .

For me, using the original times relay makes the most sense because you're making it idiot proof .

80 amp fuse is fine.

Keep in mind, the stock relay is a LOOOOONG timer. Like 1.5 minutes...

Ya need like 30 seconds, except in sub zero temps... so be ready to crank soon.

at 30F - 10secs is hot enough to crank

Glow Plug Time Interval
 

It really depends on your engine's internal health, the condition of the injectors, the IP's timing, the amount of timing chain stretch and so on .

I prefer my engine to start with one or two revolutions maximum .

atm with 68F - 3secs is enough