Glow Plug Re-Wiring

robmee · Post by **robmee** » Sun Jul 13, 2008 11:51 pm

I have some of my pics, can post more later

but here they are, instead of different color wire I did different shrink wrap. the rest is pretty much what is listed above.

It is activated by a push button switch in the cab and has a LED to let you know they are on. More pics to come.

Caddyman · Post by **Caddyman** » Tue Jul 22, 2008 5:55 pm

Just to let everybody know and to save a little time. Instead of crimping the main current carrying wires with terminals I just went to the battery cable section in my local auto parts store and purchased some short cables and used them.

vwzuki · Post by **vwzuki** » Fri Aug 15, 2008 3:11 am

Has anyone used a relay system from a Mercedes 240D?

lloydbiker · Post by **lloydbiker** » Wed Oct 01, 2008 10:36 am

The 'Ign' terminal on the regular starter solenoid was used to bypass the 'Ballast Resistor' and provide hotter spark for starting. Most British cars ran 12V coils, hence no resistor and poor start spark. (Jos. Lucas, Prince of Darkness, strikes again). Witness my Sunbeam-Talbot, which wouldn't start on starter, but with 1/2 turn on hand-crank, Boom! If your original relay is functional, wouldn't you be able to drive a starter solenoid from the original glow plug lead, providing timing? Running separate leads to each plug makes perfect sense, and the starter side terminal should easily accommodate 4 terminals plus maybe even one for a true glow-power indicator. #8 wire should be used from battery to relay (50A cap, in house wiring) #14 will do for leads to plugs (15A cap.) but #12 (20A cap) is even better. Less circiut resistance = hotter plugs.
This makes me think of the temp. fix I applied to my '95 Dodge-Cummins when on a trip to Toronto from BC. It allowed me to return home, shop for replacement solenoid contacts ($30), and avoid a $500 starter replacement. When I get my '87 Jetta TD home today (just bought) I'm going to look into this modification ( the girl said it was hard start when cold). The old 220D was so simple, everything was manual. You held the knob out 1/2 until the 5th plug was super hot, then cranked. If it didn't get hot, you had a problem to fix.

viperkepr · Post by **viperkepr** » Tue Mar 03, 2009 11:09 am

I modified my Rabbit 1.6N/A a month or so ago, and I must say it is working way better than I ever hoped. It starts better than it ever has. Granted, I put brand new injectors and glow plugs while I was at it, but wow. I set it up similar to Vince's way. I'll take some pics as soon as I get some spare time. I used the part ##s posted here. It was a lot easier than I expected also. Works like a charm, thanks guys for the info to do this mod. The only thing I'm going to add(when it gets a little warmer) is to add a LED light next to my GP switch on the dash to let me know the GPs are powered up when I hit the switch. I got all of the stuff, just need some time to do it.

TonyB · Post by **TonyB** » Sun Nov 15, 2009 10:19 am

When installing a solenoid & distribution block and replacing the original relay with a button or switch, you can save yourself some work by utilizing the original wiring to activate the solenoid instead of running new wires from the dash to the new solenoid.
Unplug the original glow plug relay and remove it's cover. Drill a hole in the cover, being careful to put it in a place that won't interfere with the relay internals when wires are run thru the hole. Install a rubber grommet in the hole.
Solder a wire to each side of the contacts of the large relay that you see when the cover is removed, run them through the hole in the cover and connect the wires to the switch or button you're going to use to activate the glow plugs.
Before replacing the cover of the glow plug relay, wedge the contacts of the large relay open with a piece of cardboard between them. This effectively keeps the old circuitry from activating the glow plugs. Now replace the cover and reinstall the glow plug relay.
Now disconnect the wire on the 50 amp fuse under the hood that comes from the dash (the one that does NOT go to the glow plugs) and connect it to the terminal on the solenoid that activates the solenoid (makes it click). Your new switch/button now activates the solenoid.

wolf_walker · Post by **wolf_walker** » Sun Jan 03, 2010 5:33 am

vwzuki wrote:Has anyone used a relay system from a Mercedes 240D?

The Mercs used a slick little all-in-one relay box dealy that does indeed have 4 separate terminals for each glow plug, fuse is built into the box also. There is a detailed rundown of it's workings in the Merc FSM, I have one laying around somewhere I always intended to try out. Very little problem with the GP system on the 240 and 300D's, not something someone paying that sort of money for a car back then would tolerate I suppose.

Here's one.
http://www.dieselgiant.com/glowplugrepair.htm

coke · Post by **coke** » Wed Jan 13, 2010 5:34 pm

Not sure if any of you that used the Cooper Bussman fuse panel (as seen here: http://www.napaautoparts.com/Search/Det ... 0254064401) are still around this thread or not. Napa has it rated at 30 amps. I assume, that is 30 amps per fuse place, so using this with the glow plugs shouldn't be a problem, and I shouldn't melt anything?

I'm getting ready to install 4 new duraterms, a ford starter solenoid, and a fuse panel with separate wire connections for each plug so I never have to wonder which ones are bad again. Not only that, I think they'll operate much more efficiently and effectively with separate wire connections and a dedicated big wire feeding all the small ones.

Post by **Fatmobile** » Wed Jan 13, 2010 11:31 pm

My Rabbit was having a hard time starting when it got cold so I checked the glowplugs.
I hooked an ammeter up to the main power supply and pulled the individual wires,
one at a time.
No drop in amps meant bad plug.
One blown 15amp fuse,
and one bad plug,.. it was the easy one #4 because I put used ones in that hole.

the vegenator · Post by **the vegenator** » Mon Jan 18, 2010 11:25 pm

When my glow plug fusible link melted a few years ago my mechanic just bypassed it and bolted the two terminals together! I wish I had known better. After reading this thread I think some reworking on my jetta is in order...

I have four new authentic duraterm plugs, and my end goal is to "pimp my glow plugs" with the ford solenoid, fuse panel, and individual wires. I think I'm gonna start off simple though, with the fuse panel, since I couldn't find a FORD solenoid for less than $35. Have the prices gone up since this thread started or am I just looking at the wrong one?

Until I get the Ford solenoid, I'd like to hook the glow plug wire from the original relay up to the Bussman fuse panel, then run wires to each plug. If this gets things running right, then is there even any need to use the solenoid as well? I don't want to fix what isn't broken.

I also couldn't find any decent ammeters online for less than $50---at what point is checking current flow necessary? Are there cheaper options?

Vincent Waldon · Post by **Vincent Waldon** » Tue Jan 19, 2010 1:45 am

You might find an answer or two here:

http://vincewaldon.com/index.php?option ... &Itemid=28

In particular... an option to a $35 Ford solenoid, and why a solenoid is a useful idea in the first place.

the vegenator · Post by **the vegenator** » Tue Jan 19, 2010 7:19 pm

Thanks! I'd seen your page before, but after reading it all the way through it makes so much more sense to me now!

I'm a little fuzzy on one point though - should I remove the Glow plug relay or does it still serve a function (for the fuel stop solenoid, GP light, temp sensor)? I see that some folks prefer manual switches, but I like the automatic-ness that the original system has.

Also, another point I need some clarification on -- is the original glow plug wire (the R/W one, from terminal 87) what I splice into?

surfcam · Post by **surfcam** » Tue Jan 19, 2010 10:06 pm

I have both on my two diesels and it works well. I just ran a $12 ford solenoid(don't know where Vince got his) from the battery. Then to the bus bar on the GP's. Then the low voltage wire on the solenoid to a switch on the dash. I think your right about the automatic part of it. It's really niece to be able to give it that little extra. I guess the only negative would be that you can stop the GP's from coming on when it warm out.

Post by **Fatmobile** » Wed Jan 20, 2010 1:18 am

I have used the glow plug relay to control the ford starter relay.

Sometimes the ford starter solenoid allows so much current flow that the voltage will drop,
enough to shut off the glow plug relay,
then the voltage will rise again and the ford starter solenoid will be triggered again.

BztBztBzt

I've had this happen on both cars I've tried this with.
Doesn't happen every time, hasn't happened on my car in weeks.
But the ford starter solenoid is loud when it chatters on and off, a bit embarassing.
This could probably be solved by hunting down voltage drops in the wire supplying the glow plug relay. Might be a bad ignition switch.

coke · Post by **coke** » Wed Jan 20, 2010 1:24 am

I did this to my car finally. I don't have the problem you described Fatmobile.

$11 1988 Ford E350 solenoid, 10 bucks in heavy gauge wire, 6 bucks in crimp connectors, and a little redneck ingenuity and my glow plug system is pimp. Minus the dedicated fuse box and separate wires, which is coming.

I noticed it did start a lot easier. It hasn't been cold enough to determine if my cold start problem is fixed yet.

Former VWDieselParts.com Forum

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