I did a bit of research here and I found that people get too little glow plug time on their relays, especially in cold weather. I have the opposite problem. Mine stays on well after 10 minutes of driving the car and it eventually killed my battery, so I had to buy a new one. I've checked out prices out there for a relay and since I just purchased a rebuilt tranny, I'm kind of not wanting to shell out that kind of money right now, especially since we have a little baby girl coming our way and we've put enough $ on the car lately. So I thought that I'd maybe just wire up a switch to the cabin and switch it on and off at will; would that hurt things? I saw the override switch a certain website out there sells, but since mine just stays on forever I thought a cut-off switch would be just cheaper and easier to install; is there anything I should know before I try this?

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[/SIGPIC]~cirrusman

1983 Mercedes Benz 300SD - Wife calls him "Chitty Chitty Bang Bang"
[SIGPIC]




1983 Toyota Tercel (Tommy, The little Toyota that could)
1965 Ford F100 (Grandma Ford)
2005 Toyota Sienna (Elsa, Wife's ride)


Gone:
1988 Toyota Pickup
2004 Subaru Outback

1987 Cadillac Fleetwood Brougham
1986 Volvo 740 GL Station Wagon - Piece of junk.
1981 Volvo 242 DL 2 Door - Hated to see it go. R.I.P.
1987 Pontiac Fiero GT

looks like new they're a tad over $100, but if $30-40 is in your price range, theres a couple up on the auction site right now

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1981 NA 300D 310k miles

A Ford starter relay and a momentary switch is a pretty inexpensive alternative and the timer God designed in your head is pretty reliable.l

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

X2.

And, you can use afterglow if you so desire on a very cold day.

That's the route I went and am very happy with the setup. It's very easy to install. Grab a solenoid at the JY - they're often right next to the battery. Take a lead off the battery for hot, and run a length of 4GA wire to the glow plugs.



To keep things looking stock, I gutted an old glow plug relay box and used the existing fuse and distribution plug so I could use the stock harness.

Here's the finished product




And here's a link to the post on how to do it - 380SL Diesel Conversion Project

The only thing that was tricky was, I didn't trust that my momentary switch would handle the load so I added a relay for safety. (Make sure you use a momentary switch to prevent burning out the glow plugs by forgetting to switch them off) I used a switch with a LED indicator for positive feedback of glow plug operation.

Attached Thumbnails

   

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

i got an afterglow relay from ebay germany; was new and only like $40 shipped, but that was last year before they stopped making them

Thank you, gentlemen, for your valuable input. Sleepstar, the one I got is pretty recent and I got it af Fleabay... I don't want to go that way again. Shadetree, that's a pity...
Kerry and Brian, how about just adding a switch to the wire that comes from the ignition? Run a wire inside the car and just flip it on or off? Would that hurt the current setup?

__________________
[/SIGPIC]~cirrusman

1983 Mercedes Benz 300SD - Wife calls him "Chitty Chitty Bang Bang"
[SIGPIC]




1983 Toyota Tercel (Tommy, The little Toyota that could)
1965 Ford F100 (Grandma Ford)
2005 Toyota Sienna (Elsa, Wife's ride)


Gone:
1988 Toyota Pickup
2004 Subaru Outback

1987 Cadillac Fleetwood Brougham
1986 Volvo 740 GL Station Wagon - Piece of junk.
1981 Volvo 242 DL 2 Door - Hated to see it go. R.I.P.
1987 Pontiac Fiero GT

Are you referring to the violet wire that extends from the ignition to the glow plug relay?

If so, you'd still need a functioning glow plug relay for such a switch to work. This switch could work to allow the driver to control the time of engagement of the relay, however, the timer in the relay would override the new switch.

That would be the wrong wire to switch. The switch would need to go in the wire that is hot in RUN. Opening that circuit would (in theory) have the same effect as turning the key off.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

The added switch could keep the violet wire closed for an indefinite period. The driver could open the circuit at his discretion. Obviously, the new switch would need to be in parallel with the ignition switch.

How does that address the problem? The OP needs to terminate the glow cycle, not extend it. It's already extended, and that's the problem. Evidently, the controller isn't paying the violet wire much mind, anyway.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Are you sure about that? Does the timer still function once the violet wire gets power?

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Point.

I am not certain if the timer functions once the violet wire gets power. We'd need to verify that.

The violet wire might interrupt the timer..........might not.

I could check it if you're interested..............

Or, we could just interrupt the run input and ignore the violet wire.

It does not. The cycle will not "time out" while the starter is engaged.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

I don't know what else can extend the glow plugs on for so long except for the relay, and I'm clueless as of how to troubleshoot a bad relay...

I appreciate the aircraft analogy Right now the relay is just overtiming the plugs, so I want to cut the time down. Kinda when the vacuum is bad and the engine won't shut off, they put that shut-off lever on the engine.

That's my thought exactly, only that I didn't know which wire to switch.

I want to put a switch on the wire that supplies the current to the relay to be able to cut it off from inside the car but I wanted to leave the relay on as it's overtiming now; the only change would be a switch added inside the car replacing the radio's fade switch and the wire cutting the relay's power wire, but I haven't checked if it's purple or what color.

I do appreciate everyone's input. This website is what have kept my old Benz running so far!

__________________
[/SIGPIC]~cirrusman

1983 Mercedes Benz 300SD - Wife calls him "Chitty Chitty Bang Bang"
[SIGPIC]




1983 Toyota Tercel (Tommy, The little Toyota that could)
1965 Ford F100 (Grandma Ford)
2005 Toyota Sienna (Elsa, Wife's ride)


Gone:
1988 Toyota Pickup
2004 Subaru Outback

1987 Cadillac Fleetwood Brougham
1986 Volvo 740 GL Station Wagon - Piece of junk.
1981 Volvo 242 DL 2 Door - Hated to see it go. R.I.P.
1987 Pontiac Fiero GT