You may or may not believe this but my truck has substantial trouble starting on cool days, much less on frigid days. If I use the block heater she fires right up and purrs beautifully but this is absolutely NOT the case if I forget to plug in. How should I begin the troubleshooting process for the hard cold start? Is there a setup for the older 7.3's that would allow me to not plug in?

 

there is a solenoid in the v of the motor... looks just like a starter solenoid, right by the water seperator.. leave it un plugged on a cool day, turn the key on an place a screwdriver across the two bigger posts.. leave it on there for 20 to 30 seconds, take it off for a little.. then on again for a few more seconds.. then try to start it, if it starts then its the glo plug solenoid, mine is currently out..

 

Excellent. Thank you.

 

Do you have access to a multimeter? If so, it's very simple to test your GPR. If you have access to a good multimeter (that has ohms on it), you can test the GPs.

Anyways, a quick test for the GPR is to place one lead on the covered post on the GPR and the other lead on a negative side of a battery. You should have the same amount of voltage here that you do on either battery. Next, turn your key to the ON position. Place one lead on the other copper colored (or oppsite terminal) and the other lead on the negative post of a battery. Voltage should be about 2 volts less than your original voltage. This means that your GRP is working

Hold the leads there for at least three minutes. Did the voltage drop at some point? If so, then the computer has shut off the GPR. All is well.

If the voltage does not drop, you may have a "starter relay" installed instead of a "Glow Plug Relay".

If the GPR does not test satisfactory, go to napa, and ask for GPR-109. It is 29.00. If you go to any other parts store, expect to pay $70 or to get a starter relay. You want the GPR-109.

Tim

 

most interesting, what is that one supposed to fit? they list the gpr- 110 and 111 as choices for our trucks. not bad for 30 bucks and a 12 month warrenty. do we know what the amp rating is on that one?

 

It there away to test the glow plugs in the truck with out pulling head covers?

 

Sort of, you can unplug the four harness legs where they plug into the valve cover gaskets and probe the GP lead contacts for resistance. But, if you don't get good readings you won't be able to tell whether it's because of the VC gasket, UVCH, or GP without pulling the covers. The very top thread of this sub-forum covers a ton of GP/hard start topics.

 

I use a 15volt Stancore, lasts forever and cost 45 bucks from a controls supply house, my truck starts @ 15 degrees with no plug. Be sure all gp's are good by ohming at the pin connection of the vc.

 

1 GP replacement - what a difference !

howdy all & thanks for the info on this forum. DIESEL MX is new to me
& my (new to me !) 92 E350 4x4 7.3 w/160k has some squawks to chase out.

van came out of Reno a week ago and had less that optimal starting (1st start cold) characteristics. van would start with 5 to 7 seconds of starter engagement after the WTS light went out and the GPR could be heard cycling - fairly loudly. again, this is a van so the back of the engine can be readily opened.

using info from this thread I ohmed out my GP's and found one - just 1 -, open/failed GP. a BOSCH replacement was all I could find locally & with THAT 1 replacement GP my 1st cold start (30 to 40 degrees) in the morning is almost immediate . . . perhaps 2 seconds, at most, of starter engagement. The GPR does not cycle and the desired start is much less smokey, rough & loud.

it looks to me as though the removed GP was original based on debris &
compacted dirt in & around the GP mount. after some searching I am considering replacing all of my GP's with these from SSDiesel, advertised as "instant Heat" (Ford NON-Powerstroke 7.3 Turbo Diesel Glow Plug Plugs : eBay Motors (item 160404678453 end time Feb-24-10 15:33:13 PST)). does anyone have an opinion or experience or advice on these SSDiesel Instant Heat GPs ? I am aware of the bad rap Autolight, Echlin, et al have & that the original Motorcraft ZD9 is the GP of choice. The SSDiesel GPs appear to be a quality product.

AND, while the GP replacement is not exactly a quickie I am inclined to replace all Fuel Injectors thereby resetting the 'clock' on a major component of my starting system & cylinder fuel atomization. What can I expect for FI replacements ?

what should I know and consider with Fuel Injector replacement regarding overhauled components, new replacements or 3rd party FI's.

thanks all for your time & info.

David

 

+1 on the stancores, don't waste your time on the NAPA's, warranty may be nice but when your sitting in the woods with a dead battery waiting for a friend to show for a jump..... never again!

 

Joe,
GPR-109 and the MR-99 are for the IDI 7.3, but work great for the PSD and are a lot cheaper.

 

So I'm seeing mixed reviews on the qualities of the replacement GPR's. It looks like the Stancor 586-903(the 15V unit) is the way to go but has some inferior construction. From what I can tell though, if it lasts, it REALLY works well.

Has anyone had experiences with the following: NAPA GPR-109, Stancor 586-902(12V), Stancor 586-903(15V)? Or any other suggestions for replacements?

I live in College Station, TX where it is 85 degrees or higher most of the year but does anually drop to the high teens and low 20's so I want a reliable replacement. Even though I don't technically need a functional unit most of the year, there isn't much that pisses me off more than going to sleep on a fair night and waking up to a 25 degree engine that's giving me the finger!

I know you all must be as tired of this post as I am but if you've ever shared my frustration then you may understand. Thanks in advance.

 

I've replaced the GPR with the NAPA-109 about a two weeks ago. I've had no problem with it, but what do you expect from a part that is almost brand new. I did check the resistance on it when I installed it. Obviously, with the key off, the resistance was infinite. With the key on (before starting when the computer was warming the GPs), the resistance was 2 to 3 milli-ohms (what the fluke meter said). I've been quite happy with it, especially with the temps here in eastern nc being in the 20s at night.

One of the most overlooked areas when dealing with the GPR and GPs is the batteries. First, you should be waiting to crank the motor over after the computer has shut the GPR and GPs off (verified with the voltmeter in your dash). Second, check the wires between the batteries. There should be no corrosion that would cause bad connections or a loss of ampheres between them. Third, the batteries themselves. The higher CCA, the better. Batteries are the heart of the system, ignore them, and they will leave you stranded.

I will openly admit that I miss Texas. Hopefully we will be transfering back to the Houston area this summer.

 

So I went to Napa and got the GPR-109. Since it is not the 110 or 111 it has the studs just slightly in different arrangement than the stocker. Does it matter what wires go where when reinstalling them? I don't believe these things are polarized so it's my understanding that as long as the large wires to large studs and small to small then everything should be kosher. Is this correct? Just wanted to make sure before frying anything.

 

You got it. I wondered the same thing when I installed mine. It was that simple.

Tim