TSU burnt terminals - cold start problem

[chickenbutt]

So I was having problems cold starting, it would crank for about 15 seconds then start with a wonderful cloud of white smoke.
So I replaced the batteries, glow plugs, Nartron white label EESS and added a ground harness. No change with cold start problem.
I pulled the connector off the TSU and it looks as though a couple of terminals are burnt/missing. I suspect that there was a poor connection here and over the years the terminals getting hot eventually disintegrated.
I’ve seen many hard start threads on here and do not remember ever seeing this problem.
In the pictures there is some dark colored grease that is a little deceiving.
Looks like a PIA to replace the harness!

 

[juanprado]

I wonder if that is right tsu for that box?

 

[Mogman]

I don't see any burning, as above I don't think that is the correct TSU, not allot of current going through those wires.
I have said this many times, you should install a dash lamp connected to one of the glow plug wires, then you will always know what the glow plugs are doing'
What about the wait light, is it staying on for about 8 seconds or so when cold?

 

[86humv]

Thats the correct TSU.
You never said if wait light comes on, and how many seconds.
All those connectors are missing a socket...and black stuff probably dielectric grease.

 

[chickenbutt]

Thats the correct TSU.
You never said if wait light comes on, and how many seconds.
All those connectors are missing a socket...and black stuff probably dielectric grease.

The wait light comes on for the normal 8 seconds or so when cold, the only difference that I noticed is that I don’t hear the slight buzzing sound that I always heard after the wait light goes out. When warm it starts right up.
Like Mogman said, I wouldn’t think there would be high current at the TSU, so they are probably not burnt.
When you say the connectors are missing a socket, are your saying a couple of them are unused?
Possibly just a bad TSU?

 

[TOBASH]

Why not just build an idiot proof PCB and forget the TSU. Plans start on Post #51 with schematics. (Several other Steel Soldier members have and are super happy.)

How to bypass PCB? I am aware some HMMWV owners have done it. TOBASH

good to know, I have fixed my location... Then why is your IP resolving to a different state?

www.steelsoldiers.com

If you don’t want to build the more robust box, PM me and I will sell you one.

Happy to help and and sell you one BUT you will be even happier if you DIY.

Easy peezy.

 

[diesel_dave]

The wait light comes on for the normal 8 seconds or so when cold, the only difference that I noticed is that I don’t hear the slight buzzing sound that I always heard after the wait light goes out. When warm it starts right up.
Like Mogman said, I wouldn’t think there would be high current at the TSU, so they are probably not burnt.
When you say the connectors are missing a socket, are your saying a couple of them are unused?
Possibly just a bad TSU?

Have you checked to see if the glow plugs are actually energized during those 8 seconds?

 

[Mogman]

If the wait light is acting normally than the TSU is probably OK, as RWH said you need to confirm you are actually getting 24v to the glow plugs (why I suggest installing a panel lamp on all Detroits) but of course you can just connect a voltmeter to one of the glow plug leads..

 

[chickenbutt]

Well, shame on me, I should have followed proper troubleshooting procedures instead of going with my gut feelings.
I tested a few of my new glow plugs and they are all reading high resistance, and I have the bonus of a stuck swollen one as well. I tested the original set of glow plugs and they are shot as well.
So, I would think my original EESS box toasted both sets of glow plugs…. right?
I pulled a wire off a glow plug and I get 24v that stays on after the wait light goes off.
Is my 2nd EESS box toast too?

 

[Mogman]

After the wait light goes out you should see the 24V pulsing on and off for a couple minuets but not on steady or yes it will toast the glow plugs.
Edit, if the second box is also bad, maybe invest in a CAMO manual box.

 

[chickenbutt]

Why not just build an idiot proof PCB and forget the TSU. Plans start on Post #51 with schematics. (Several other Steel Soldier members have and are super happy.)

How to bypass PCB? I am aware some HMMWV owners have done it. TOBASH

good to know, I have fixed my location... Then why is your IP resolving to a different state?

www.steelsoldiers.com

If you don’t want to build the more robust box, PM me and I will sell you one.

Happy to help and and sell you one BUT you will be even happier if you DIY.

Easy peezy.

Thank you TOBASH, but I’m a bit of a purist . This thing worked flawlessly for 5 years so I’m determined!

 

[TOBASH]

That’s the beauty of this hobby. You can be a purist or a renegade and it is all fun.

Good luck!

 

[TOBASH]

I reread your post. Please forgive my additional response.

You would seem to have a toasted box.

I know you’re a purist but this can become an expensive issue if an exploded plug scratches a cylinder.

I worked with others including CamO to design mine and I published the plans as freeware.

I manufacture mine so it all fits inside a traditional PCB/EESS, so it looks stock. I believe CamO does the same.

He and I sell these boxes too, but this is DIY stuff.

IMHO, use the force Luke, and make a PCB bypass using the link. (Last time I’ll mention it.)

I feel bad for ya’.

 

[Mogman]

Had you installed a dash lamp connected to the glow plugs you would have been able to see that the controller was frying your glow plugs and may have been able to avoid it!

 

[chickenbutt]

Had you installed a dash lamp connected to the glow plugs you would have been able to see that the controller was frying your glow plugs and may have been able to avoid it!

Yes, true…..maybe I’ll incorporate that into an under dash light to keep originality

 

[Mogman]

Whatever floats your boat!