Ok, after about 10 days of off and on working on my bro-n-laws truck. I got it running. I've got the dead short isolated to the glowplug relay. There is a ring terminal that has two wires coming out of it(1 yellow and 1 brown), I assume they are going to the left and right bank glow plugs. I cut the brown wire and my dead short went away. Truck quit blowing fuse, and with a tiny little snort of ether, it started up and ran just fine.
My question is, where are the glowplugs at? I'm guessing that they are under the valve covers???? Any special procedure for changing them? Torque specs? Should I change all of them, or just the one bank thats currently disconnected? Also, which bank is the brown wire going to? Is there a replacable internal harness that could possibly be shorted?...
Any help would be greatly appreciated!!..

 

I know that the glow plugs are under valvecover by the injectors. You will see where they are when you pull the valvecovers off. I would do them all while you are in there. Replace the relay too. They are the most prone thing to go out on the powerjokes.

 

The harness plugs into the gasket on each bank, then there's an under valve cover harness inside that plugs into the inside of each gasket. Generally you can disconnect the connector to test the glowplugs on each bank without removing the cover. The glow plug wires are the outer ones on each connector. (brown wires on one side, yellow on the other.) Have a good look at the under valvecover harness on the brown side. Probably a wire snagged under a rocker arm, or such. Not a bad job, unless it's an Econoline.

 

Agreed with everyone, if you are going to pull the valve covers change all of them, even if they test good, they have a habit of swelling on the tips after a while then they are prone to breaking off. Very easy job, I have seen as others have stated, wires caught on rockers, glow plugs shorted, valve cover gasket worn-(not common, also $200), and the relay's wiping out, do the relay also.

Tim

 

Thanks for all the replies. Sometimes I really hate being the designated "family" mechanic. The relay tests ok, and i've still got the YELLOW lead hooked up, I just cut the BROWN one loose when I realized that set of leads was causing all my problems. I went ahead and bought a half set of glowplugs this morning, but after reading these replies, I might as well go ahead and buy a valve cover gasket too. The engine has 240-250K HARD, abused, neglected, and mis-treated miles on it, so realisticly, i'm not sure if I'll do all eight. If it were my truck, I would definitlely replace them all. I'm sure everybody knows how those brother-in-law deals go.!!!.. Somehow, you end up spending more money getting his truck running than HE does!!.
Sounds like all I need to do is determine which connector has brown wires on each end of the connectors? Anybody have a good idea of what they should OHM to test good?.. Guess I could test one of the new ones and factor in a little for wire resistance?
Once again, thanks a LOT for all the replies, its really difficult troublshooting an engine you aren't familiar with when you don't have a manual or any way to read codes. All you have is blown fuses, dead batteries, a low fuel light on, and a severe starter malfunction. (try to crank it, and when you turn the key off, the starter keeps turning the engine over.) WHAT A MESS. Anyway, got the starter fixed. NOTE to self: NEVER buy a starter solenoid from O-Riley's or NAPA!, Use Motorcraft part ONLY!

 

From memory, 12 ohms or less is good, (note the first part), an 8 pack of glowplugs are about $40 bucks, a glowplug relay form napa is around the same price, if you go to Ford the relay is $70.00, (ouch),(however you should do both). I HIGHLY doubt you need a valve cover gasket (possible, but not likely), they are reusable so you can remove the valve covers with no worries, (you will see when you pull them). The biggest problem you may have is damaging the valve cover plug by unplugging it, so just use caution, and when you have it off look for pushed in or bent pins, (then its replacement time). Don't forcefully remove the glow plugs if one of them starts to bind after you unscrew it, (swollen tip), hit it with penetrating oil and work it back and forth until it comes out, and make sure it is complete, (no missing tip). Once you are done change the oil and f/f and down the road he goes.
I hear ya on being the family wrench , you got to love them though.

Tim

 

I always use a test light to test glow plugs, put the clip on 12 volts, and touch the probe to the glow plug. And good advice above about changing the relay. They cause a lot of trouble on those trucks. They like to build up resistance across the contacts, then they get hot and melt the wires etc.

 

If you take the valve covers replace all 8. It's a piece of mind. A little bit PIA They don't give you much free wire to work with

 

Well, the continuing saga of this little project will be on Saturday morning. Now that I'm armed with some intelligence and direction (that may be a scary thing!) I'll see if I can get it running on its own and post what all I find broke, burnt, damaged..etc..
On a somewhat related subject, anybody know how to run an injector duration test, cutout test, and actuation pressure test on the HEUI system? Or if its even possible on the PSD? I know how to do it on a CAT, but with the Ford control system, it may not even be possible. If not, other than a temperature gun, how do you troubleshoot a weak injector?

 

I've used a Snap On scanner several times to do cylinder balance and injector buzz tests on various PSDs.

 

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What he said, an injector buzz test will activate the intensifier piston, you will here one if it is goin bad it is a KOEO test, also a cylinder contribution test with KOER, both tests will help you id a pending injector failure. Yes there is a test port on the HPOP, minimum spec at idle is 750-800psi, and 2,500-3000psi at rated max rpm. As low as 700, and 2,500 psi are acceptable. Cylinder # 8 is a long leed injector and is the last one in the circiut to get fuel, it is also the first one to usually fail, when you fire off the engine listen for a slight knockin or rapping noise, this is called "rapid combustion" is a known issue on that engine, esspecially if it has a weak #8 cyl, (it also intensifies the noise), and it is the reason for the long leed injector.

Midwest Fuel injection has pretty good deals on HPOP's and injectors, and since you work at Cat, they may give you the commercial price, their affiliate in my area is Metro Fuel Injection, they are very good people to deal with.

I have to change out the sticks on a 1995 3406E, how bad of a job is that, I have never done one. Thanks

Good luck,

Tim

 

You shouldnt have to replace the gaskets, they are reusable. I've done the glowplugs on my 2 powerstokes and on my buddies powerstroke. Its pretty simple and straight forward to do, I found slipping a small piece of vaccum tubing on to the glow plugs helps to get em out. You cant get the deepwell socket off after the first three or four turns so the vaccum tubing is a must. If you have anymore questions about powerstrokes just send me a pm and I'll try to help ya. I unfortunately have had two strokers and have a few stupid friends who still drive em and I know what you mean about being the family mechanic, I seem to be the one in my family. Good luck with it man

 

Its one of the easiest engines to change injectors on. I don't work on OTR stuff, everything I work on is large displacement diesel and natural gas engines. Occasionally, I will work on a C-15, which is pretty much the same as a 3406E. About the most cumbersome part is getting the rocker shaft assemblies back aligned and turned just right WITHOUT smashing a finger or two. Cat makes a tool for handling the rocker shaft assemblies, but I've never used one.. (Just don't really work on them too much)
Setting the injector height has got to be one of the easiest Cat EUI engines to do. Once you see the injector height setting tool, you will understand what I mean. Just make sure you buy new injector holddown bolts. Its cheap insurance against a previously overtorqued (a.k.a. STRETCHED) bolt that can fail, and your new injector ends up sticking out of the valve cover. If you need any specific info, pm me and I'll help ya all I can.

 

Well, Friday night I pulled the R/S valve cover and replaced all 4 glowplugs, checked the L/S and found one bad one, replaced it too. ohmed the wiring harnesses, everything ok. Put everything back together and hit the glowplugs one time and she fired right up. During the course of it, I noticed a hose coming off the intake going what looks like a primitive sensor on the firewall( maybe boost pressure sensor??? ) was broken at the intake, fixed that too.
Anyway, it lives. Thanks to everybody for all the help, couldn't have got it fixed without some great information from ya'll. I'm sure it won't be the last time he tears it up.