does anyone know the wiring schematic under the dash for the glow plugs? something is wrong under the dash, i have replaced just about every part that has to do with the glow plug system, i want to make sure i have the relay wiring correct. or does anyone have pics of it. i work great off of pictures. thanks alot

 

This what your looking for?

 

perfect, thanks alot

 

Branden,
If you have the relay out on the engine wired correctly the only thing under the dash related to the glow plug system is the wait to start light.



Well I guess the ignition switch is also related since it has to send power to the ignition terminal of the relay.

 

yes i have the wires on the relay correct and its a new one.

 

I had replaced my relay on my 7.3 but it was made in China and made a weird buzzing noise when glowing the plugs. Shortly after installing it the batteries went bad. I finally bit the bullet and bought a Motorcraft controller. Now they work great. You may have gotten a bad relay. Some things are better to buy name brand. So many after market parts are made in China and are unreliable.

 

i hear you on that. everything i buy motorcraft, but i need my truck up and napa had the part so i just bit the bullet. i hope this chinese crap didnt mess up my brand new glow plugs i put in.

 

i replaced my solenoid on my modual and had the same noise got truck to start on 2nd try but no luck since thinking new glow plugs or and new modual found glow plugs on ebay 59.00 for wellmans or 25.00 for bosch so what do you think

 

thats my problems

 

Tow pro do yourself a favor and look at the glow plug posts over the last couple years.
I think you will find the post 100 to 1 saying any brand including wellmans and bosh only lasting from 1 start to 1 week while the beru's are lasting years.
I can count on 1 hand the number of guys that have given good reports on ANY other brand since I have been following this forum and that is about a year longer than I have been a member. That said it is your money and time i'm just the kind of guy that only likes to fix a problem, also nobody warranties glowplugs.

 

Wanna guess how many posts I have read about Autolite, Champion, Bosch, Wellman and some others I can't even remember the names of that last 1 start or maybe a week before they died.

I have been reading this forum for over a year before I joined.

Motorcraft/Beru is the only glow plug I will install in my engine, period.
Even though I am now running a 93 7.3 wiring harness and ZD 9's in my 6.9, I still run the 86 style glow plug relay with manual control because I like it that way.
If I were to run an automatic controller, I would install the new style 7.3 controller because I think it is the better of the two.

When you need glow plugs to start your engine when it is cold and you live in a cold climate, the glow plug system is not a good place to cut corners if you expect your truck to be reliable.

Alternators, starters and battery wiring are three more places that only get top shelf parts in my truck.

Our temp is supposed to be in the mid 20's tomorrow morning, the block heater is not plugged in.
I expect the engine to be running before it turns over a complete revolution tomorrow at 6.30 AM just like it did today.

 

I am not going to argue with you. I am using the motorcraft glow plugs myself now. Still i have to say that I installed 8 wellmans 14 months ago. They lasted over a year. I had no problem removing them either. The reason I got them was that I bought 8 gp`s at MWFI thinking i had ordered ZD-9 plugs.

Now I got a problem myself. Can`t find any solution searching throu the old posts. All plugs are ok. WTS-light on for about 8-10 sec.( -3 Celsius).
Light go off- starts fine. Looking at the Amp.-meter, the gp`s are still on for 8 sec. No afterglow cycling as it used to be. This is telling me that the gp`s are on for almost 20 sec. I am afraid they won`t last for long.
Any suggestions ??

 

Check the controller ground wire and the battery to engine grounds.

Any resistance in either place will cause the glow plug time values to change.

Also inspect the engine harness to chassis harness connector.
Pay close attention to the connector on the side with two large AWG wires, they are the glow plug power wires.

Very common for a bit of corrosion in the connector to make it overheat and melt.
Once that happens, the only fix is to splice the glow plug power wires around the connector.

If you are running ZD 9's, then you have the new style system, and those wires will have battery voltage on them at all times, so be careful while working on them.

A 10 AWG wire will have enough juice to burn a hole in something or you if it gets shorted out.

 

HI I need help with the wiring to my gp relay I had a motorcraft relay three pin now the replacement has 4 pins and I find my self not knowin g where to put the starter wire

 

sound similar to my issue which i colved by creating a long lead wire from the negative battery terminal which i then soldered to the ground wire from the GPR. It stopped the erratic clicking after the cold high idle and it regulates the temp way better. I have got my truck nailed down like Dave's and if it is above 20F i can barely turn the key and it is running. most times we are in the mid to upper 30's in the am and it is an instant start in that i never get to hear cranking. The nice part about that is that i know exactly when something is going wrong. like when i had a glow plug die( yes ZD9) when my system locked on and ran for 30 seconds before i knew what was happening. I only lost one and there was zero swelling. The ZD9's i buy at ford are 14.50 each and the POS autolites from lordco are almost 12 with my discount. Its cheap insurance.