Get me Grounded!

[dieselrunner]

At least I think thats the answer.

Problem is the glowplug system (somewhere along the line) does not function properly regularly. When the ignition is turned to "ON", normally the glowplug system should begine to heat and cycle. Well this only happen about %10 of the time, I can tell this by watching the volt meter on the dash. Im aware its the stock "idiot light" guage, but differences can still be seen. Times when the system doesnt work, is when the volt meter shows a reading in the "normal" range and no draw on the batteries for the glowplugs (this is confirmned with a No Start). Times when the system does work the guage reads lower on the scale indicating a draw on the batteries (confirmned with Start). Had this problem for about a year, but it is getting worse. Which leads me to belive it is a bad grounding somewhere. So advice is needed as to where I should be looking for the culprit. I am aware of the ground for the Controller/Relay, behind the intake, and will be checking there. Is there anyone else with this problem or with some other common failing grounds/connections?

Thank You in advance.

 

[jperecko]

Not 100% on this but I think a lot of people have had issues with the stock "idiot" light and glowplug controller on these and prefer to just have a manual override with a push-button.

Check out this-
http://www.oilburners.net/forums/showthread.php?t=8776

 

[Agnem]

If you still hear the relay clicking, but don't see the voltmeter move, it is most likely that your GPR has bad spots on it, and is only contacting some of the time. Just replace the GRP with a motorcraft one.

 

[sle2115]

Run a ground wire from the negative battery post to the relay ground connection on the intake. (this is a test from the Ford service manual). See if that fixes it. I just ran the wire temporarily and it did not fix mine. If it doesn't, check voltage to the relay with a meter and cycle the gp's. I had voltage and a good ground which only left one thing, a failing relay. I replaced it and it never did it again! I'm guessing your relay is dying a slow death as mine did evident by the many cans of starting fluid in the truck when I got it!

 

[mech140]

does any one have any advise as t put a manuel switch or push button on the glow plug relay to over-ride the gpcr and make it work this way? I have an 88 7.3 and ive replaced the glow plugs ,glow plug relay, glow plug relay controller,newfuel injector kit wiyh o-rings and lines,fuel filter,fuel tank control valve,and an in line electric fuel pump in addition to a new mechanical pump also did work an return fuel line to tank. with all this the s.o.b still wont start with out a tiny spary of either each time i shut it off even after it is warmed up .any help wold greatly be appreciated.i'llalso include my email [email protected]

 

[Agnem]

Hazard Kentucky! MY GOD! I know where that is, and I've been there.

There is some troubleshooting you should do before you go to a manual. The 7.3 system works really good when everything is right. So if it's not working, there is a problem, and you can fix it easily. Start by rigging up a test lead on your #2 glow plug. Arrange a way to be able to put a voltmeter probe on that glow plug at the connector. The connector must stay attached, so you will need to use something like a fine piece of wire under the connector to be able to sense the voltage there. Set your volt meter to read 12 volts, and put your ground probe to a good metal surface on the engine. Have someone turn the key to the on position, while you watch the meter. It should start out around 7 volts and slowly rise towards 12. Note the start voltage, and also the maximum voltage just before it turns off, and how long it took between the two. Report back the results.
On edit... if your having problems starting when the engine is warm, you most likely have a timing or IP issue.

 

[mech140]

appreciate the info i'll try it and let you know. whats a delta,Pa guy doing in a outa the way place like this? small world aint it.

 

[mech140]

looked at your pics Mel nice rides ill get some pics of mine soon i have the 88 f-350 drw reg. cab with the 7.3 idi and an 97 f-250 7.3 power stroke heavy duty

 

[mech140]

thanks JPR will also check that also.

 

[JPR]

I was trying to find where the ground wire originally attached, but could not. In the attached diagram, it shows the ground wire now attached under the front mounting nut. On my truck, the ground was not good after moving the relay, so I ran the ground to the alternator bracket.