hello all,
i was wondering, with the ecxeption of the type of connector employed, are there are differences between these glow plugs:

OEM part number: ZD1A 83-86 6.9 idi (with narrow spade connector)
OEM part number: ZD9 87-94 6.9/7.3 idi (with bullet connector)

such as thread. length/dia, duration of glow...?

thank you in advance!

 

The ZD1A and the ZD9A are interchangeable, as in the bottom parts of both looks the same and you can put ZD9s on an early 6.9 motor in place of the ZD1s if you're also converting the controller to the solid-state one used in the '87-'94 trucks. Duration of glow is where they differ greatly - ZD9s glow for 15-20 seconds depending on ambient temperature, whereas the ZD1s can only handle about half of that - more than 10 seconds glow on ZD1 plugs is pushing them hard.

 

I am running zd9's on my 6.9 (originally had zd1's)...they worked with my original controller no problem, but now I am running them manually. After sitting all night, 6 seconds of gp activation and it will start on the first compression turn....once in a blue moon it wants an extra 2 seconds of after-glow, but thats only been like twice.

to the original question totally interchangeable, you just have to swap the electrical connectors.

 

Timothy, I wouldn't install ZD1s in a solid-state system that requires ZD9s - the ZD9s can handle up to 20 seconds of glow time, the ZD1s cannot, so if the controller decides to pull a 17-second glow cycle and you have ZD1 plugs in the system they would be toast. ZD9s in a ZD1-based system, that one works, yes.

 

ty for the info.
i understand some GPs are internally limited to certain temperatures
to prevent burnout...

you mentioned glow cycles. what are the lengths of different preset cycles.
and what are the corresponding [engine block] temperatures that dictate their
duration?

reason for asking, my f-150 supercab has a 6.9 idi with ats turbo.
quite a bit of blowby, anticipate difficult winter mornings therefore looking to
fab a glow system that has no variables other than the control i exert through the momentary on switch. in other words only wires, connectors, fus(es) and
a heavy duty switch.

does any one have suggestions or hopefully an existing scematic for such a system? is it best to fuse each GP individually? or per head (bank).

ty!!!

also what is the dry weight (no fuel) for an '85 f-150 supercab with ATS aftermarket turbo - no intercooler, no other mods.
how much do the 8' bed and tailgate weigh?

 

mlsc....thats what I have...newer plugs, older control; we are on the same page...

Volume, keep in mind there are lots of variable for the duration...but in short it comes down to coolant temp, and each motor is a little different. On mine I kept all of the factory equipment in place, however at the relay on the fender instead of being closed by the controller, it is closed by a momentary switch in the cab...the quick dirty and simple was to change the connectors at the GP's to bullets, install the zd9's, and run a wire from the fender relay to the dash switch...dash switch is fed by a wire that is hot only in the run position. Took a little of experimenting as far as the glow-time, but on a 60 degree morning, 6 seconds and she fires right up...other guys using a manual controller have different times for their trucks. The main reason I went with the zd9's was cost and the fact that they would take a longer glow time if necessary.

Hope this helps you out

 

The length of glow cycle depends on the engine coolant temperature at that time - I have no tables, but my truck at -5F will glow for right about 20 seconds, and at 80F it will be as short as 7 seconds or so. This is the 7.3 solid-state controller, by the way, unless your 6.9 engine is an '87 model it won't have that and I don't know how long the old-style controller glows the ZD1s. Blowby actually don't affect starting, mine has quite a bit of blowby and she can start on just glowplugs at -5F (even tho Ford says plugs are only good down to 20F and anything below that needs the heater plugged in). Oh yeah, and there ain't no such thing as and F150 with a 6.9, unless someone dropped the diesel in that truck replacing the original powertrain - halfton Fords never got the IDI diesel option, only F250s and F350s had it. You should use a big relay for the glowplugs, like the factory did, as the plugs pull good 200 amps and there ain't no automotive switch out there that can handle that. Do you still have the factory setup? You can do like Timothy and just power up the relay through a manual switch, this is what I do when I want to override the controller (altho I have some other mods done to the system too, so it really don't behave like it should unless engine is cold).
No clue on that, like I said there were no F150s with the 6.9 from the factory... The bed is a few hundred pounds, it takes 6 people to comfortably lift it and move it around. Tailgate I'd say would be about 30-40 lbs.

 

correction. my f-150 is a 250 oooops. f-250 XLT. so is it likely to have a 6.9? also are the mid eigties f-250's twin i-beam or coilspring?
this truck has single rear wheels, would that be a 3/4 tonne axle? are there stampings on the axle that could confim?

I mentioned blowby as a reference to general engine condition, have not done compression check yet...

a big solenoid.. duly noted. that shall be the switch I will use do you have details on timothy's setup or your system's?
should I just get another off a wrecker's GP system?

as to weight, title says 4630 lbs. however it has a douglass service bed on it right now (800 - 900lbs) , which I will be selling to attempt to recover some of the investment. anyone interested? I am in central CA.

cavitation is supposed to be a problem with 6.9 but particularly the 7.3 engines.
do you use special coolant or an additive to combat it?

TY. M.L.S.C.
btw aussies main problem is roos, not cows ;~>

 

I just completley re-wired the engine bay of my truck and put in a manual GP switch. I used a starter relay (incorrectly called a solenoid by some) to activate the gp. Wiring the switch is pretty simple as you are only handling a couple amps. Make sure you don't undersize the wires for the GP's themselves.

 

Like bacon said, pretty straight forward....you want heavy gauge wire from the batteries to the starter relay (used for the glow plugs...not the starter itself), and decent gauge wire (preferably with some sorth of heat protection) running to each GP. Then a wire running from the activation terminal to the cab switch, and switched power.

Where in central cali, and how much?

 

bakersfield - not far from the factory actually. but i could deliver if needed.
dunno. new they start @ $6K, this one is in great shape all compartments lock.
please make an offer and pass on to anyone possibly interested.

augie.oglethorpe@gmail.com

 

how many amps do all 8 GPs use combined?
also how about fuse(s) do they become unnecessary with a HD relay??

ty,
john

 

I don't know exactly how many amps these can pull, but modern self regulating types can pull up to 200 amps total. If you are looking at wiring size, the stock wiring uses 6 guage from the battery + to the glow plug relay and 14 guage to feed each 4 plug bank (one 14 GA wire to the left bank and one 14 GA wire to the right bank). I used 12 GA wire to each bank just to be safe.

I didn't fuse the GP circuit, but you probably should. The stock setup had fusible links for each 14 guage supply wire and a fusible link for each glow plug. That's 10 fuses for the glow plug system!

 

this is off the Ford_diesel@yahoogroups.com mailist.

person at the bottom started the thread the guy rambling on about
VWs and Benzes is me, then followed by replies form 2 different ppl.
what do you guys make of that?


"Yes,
you just proved my point, huh!

The ampere rating of a motor protection device is up to 5 times the actual running current because motors have little res. upon starting.
That rating on the starter relay is for a very short period, not to be used for any length of time. Why do you suppose you don't crank for long periods? Would the starter motor over heat?
huh!



Huh?
VW's use a 40 AMP fuse, 5 cyl benzes use 50 AMP.
therefore a 8 cyl *should* use 80 - 100 amps.
the combined CCA of both batteries on my 7.3 is
1800 and it uses them ALL

therefore the starter uses 18x as much power
as GPs would. starter relay should be well within capacity.


Hi
Starter Relays do not have the rated ampacity required for glow plug relays!
Good Luck, Bob


>
> maybe someone here can give some advice on my technical problem. i recently swapped in a 7.3 IDI NA engine from a 1993 ford F-350 into my 1979 ford F-150. i have replaced all of my sensors with new, made a new wiring harness for all the sensors and glow plugs as well as fuel pump. my original glow plug relay was failed so i used a stardard ford started relay and 10 gauge wire to the glow plugs. heres my problem, i am getting power TO my glow plugs as checked on the terminal of every connector but the engine wont start on its own. its only pulling 3 to 4 amps so i know something is not correct there. if i shoot just a small amount of ether, it will start and starts fine after that. the plugs are new bosch units from a reputable shop and i do have mechanical abilities. anyone have an idea why this thing wont start on its own? thanks for the help!"

 

The glow plug relay is the same as a starter relay. Go to autozone and buy a glow plug relay, it will look almost exactly the same (the mounting style may be different). The IDI starter uses A LOT more current than the GP system. A starter relay is generally not rated for continuous amps, meaning you cannot run anything for a long time, like minutes (You CANNOT use a starter relay to run an electric fan for example). Starter relays are rated for surge amps only. Running a set of GP for 10 seconds or so is no problem for a starter relay. BTW, Autozone didn't have a glow plug relay for my truck in stock, so I bought the starter relay instead, and it works fine.

As far as your truck not starting: Check for continuity between ground and the positive terminal of each glow plug, if you DO NOT have continuity, the GP's are bad. (or use a test light between battery + and each glow plug terminal. If the test light light turns on, the GP is good, if it doesn't light the GP is bad. )