Blew something up...

[whelmed]

So have been going slowly on the repairs and upgrades on the hmmwv. The glow plugs were in a bad state and wouldn’t start without starter fluid. I have the newest control box in there which was a pleasant surprise.

Anyhow, while taking the 2nd closest plug to the firewall out on the passenger side my wrench slipped. To my horror it hit something and started arcing, I tried to knock it out of the way and it stopped. Quite nervous about putting my hand back in there I disconnected the battery and then took out the wrench. I’ve never been in a situation where I’d have to be worried about a live hot in an engine bay with the key off...

So after plugging the battery back in, I don’t have power anywhere. Could be - master fuse, or maybe the harness. I’d like to check simpler first. Any thoughts here?

 

[kblazer87]

I would start with what it arced against and follow outbound from there. I know very little about the hmmwv electrical system but if a computer is somewhere in the loop it is probably a goner. This is why most manuals tell you to disconnect the batteries when working under the hood.

 

[NDT]

Battery probably melted off a link inside. Can't withstand 6000 amps for long. I bet you don't pull that again.

 

[dilvoy]

Start buy checking the large cables that are connected to the Starter.

 

[gimpyrobb]

For future referance, Pull the negative wire next time your working in ANY engine bay. The potential is ALWAYS there to arc if you don't.

 

[whelmed]

So I wrote that while at work as I had to run in after messing up. Looks like the wrench landed on the starter and melted the hot cable connector there. What bad luck to have the wrench fall there. Fudge. Made a connection and the lights turned on so I’ll have to crimp a new end on and then see if she starts. Not going to try till I have a good connection cause that’s a heavy duty cable. Glad it went quickly rather than setting the vehicle on fire.

Some real sloppy work by me. Bah.

 

[patracy]

We all make mistakes. The upside is, in the grand scheme of things, a burnt out cable is a low price to pay. I went through this with my 1008 a few months ago. (Alternator belt was slipping, I tried prying on it while running with a screwdriver, hit the 24+ terminal when I slipped and all the magic smoke came out!)

 

[1 Patriot-of-many]

You're going to break a lot more if you use starter fluid. It's a big never with glow plugs.

 

[dohabandit]

1) Always remove the negative ground wire. I remove it even when charging the batteries and I never charge them in series. I charge each battery separately at 12v. (leave them connected though except the ground). Use a SHORT wrench. And it is recommended to wrap it up with PVC tape.
2) NEVER EVER use ether starting fluid in a diesel engine. They are high compression and you will blow your head gaskets out. Once you blow your head gasket your engine will die either a slow or fast death. Either way, eventually water is going to get into your cylinder (lots of white/gray smoke). Then you will have a lot of water in the cylinder and your engine will try to compress that water. When that hydraulic lockup occurs, your connecting rod will snap and then that will punch a hole in the side of your block.
3) If it won't start, then you need to go through the troubleshooting steps. Diesel engines are simple. Fuel goes in, they run. Fuel doesn't go in, they don't run. Find out why the fuel doesn't go in. Could be MFI pump, shut off solenoid, fuel filter, fuel pump, air in fuel lines, etc etc.
4) Glow plugs should be removed carefully with an extractor and replaced with non-swelling type. Glow plug controller can be checked as well. The plugs just make starting easier, but even without glow plugs if your engine isn't in a very cold climate, it should start if there is fuel delivery.
5) When you are reconnecting those battery terminals, make sure you clean them up well with wire brush and tighten them well. I have seem loose terminals create showers of sparks as the current arc's around. (fairly disturbing to witness)
6) The electrical wiring in HMMWV is pretty simple. If you don't have the wiring diagram, let me know and I will send you the PDF. Start by checking the main fuse which is in the battery compartment. With a wrench shorting out 1400 CCA's, you might have done damage there. Did you also check the batteries? I modified mine somewhat and put in the vertical 24v bus bar. There is a grommet on the body and a pass-thru from the fuse area into the underside where the cable to the starter attaches. You might have burned out that pass-thru. (mine did when the grommet failed somehow and that was when I ripped all of that out and upgraded it to the newer bus bar type) I can send you pics if you like.

 

[1 Patriot-of-many]

Don't agree with #2. Never use ether with glow plug diesels, Most military diesels come with ether systems that meter the amount. My M35a3, M923, M923A2, M931A2, M936A2 all came with ether systems, specifically quick start.

 

[dohabandit]

Read this link regarding the 6.2L and 6.5L diesel engines in the HMMWV.
I imagine the military thought process is "get this truck moving NOW". Diesel techs I have talked with say to use another type of oil, ATF, etc.

http://www.thetruckstop.us/forum/th...n-result-from-ether-starting-fluid-use.46065/

 

[Retiredwarhorses]

There are different types of diesel motors, direct injection and Indirect Diesel engines.
IDI should never use starting fluid....DI’s is no problem.

[h=1]INDIRECT INJECTION VS DIRECT INJECTION[/h][h=2]IDI VS DI DIESEL ENGINES[/h][FONT=&quot]Indirect injection, or IDI diesels, were much more common in the 80's and early 90's, but have been altogether replaced by more efficient direct injection, or DI engines. The names can be misleading, as the difference between the two engines is not in how fuel is injected, but rather where it is in injected. IDI and DI engines have different combustion chamber designs, the later having a more traditional design while the IDI has a "pre-chamber" in which fuel is injected into before traveling into the actual combustion chamber. All versions of the Power Stroke, Cummins, and Duramax diesel models are direct injection diesels, where as International's earlier 6.9L/7.3L and General Motor's 6.2L/6.5L motors had pre-chambers and therefore fall under the category of IDI's.[/FONT]

 

[dohabandit]

With the 6.2L being IDI type with glow plugs in the pre-ignition chamber, do you think it would be safe to just disconnect the glow plug wires and then toss some diesel/atf down the intake manifold?
I really want to get my engine turning for a while to see if my MFI pump will unclog itself. I have the inlet valve soaking in diesel kleen, but no luck so far. I am thinking to remove the diesel clean and fill it with stanadyne injector cleaner or seafoam. I believe both are naptha based which should help to dissolve any deposits.
The inside of the stanadyne looks very clean. No corrosion, no varnish. Looks like new, but the inlet valve was stuck pretty bad until I manually moved it around a bit. I think whatever gummed up the inlet valve also gummed up the distribution valve.

Have you ever sprayed regular carb cleaner into a MFI pump?

 

[dohabandit]

I was also thinking to use compressed air on the fuel inlet and force carb cleaner through. Thoughts?

I have had to remove a stanadyne MFI pump before and get it repaired/rebuilt/replaced and it is a real pain in the ass.

 

[maccus]

There many reasons to have a master disconnect on the ground cable of the batteries. I put them on all my trucks. Always leave the switch in the disconnected position when the truck is not running. Stops me from doing just what you described happened to you. We all have said to ourselves " Ahh I am just going to do this little thing to my truck no need to disconnect the battery".........RIGHT !! Then the smoke........