No crank after welding

[89PSD]

Well so i wanted to change my exhaust setup so I welded in a X pipe in it. I was almost done welding (had to weld on the hangers) but wanted to hear what it would sound like. so I turned off the welder (still left gound attached to the truck) then reconnected the battery and hopped in and no crank!!
I can hear the fuel pump turn on, battery is good.

Then i tryed again and my friend who was standing by the front of the truck said he saw a flash of light and smoke over by the area where the main engine wiring harness is (those bundles of wires by the brake booster). That general area.
Any ideas on what happnened? where are the fuseable links in the truck?
89 F250

 

[89PSD]

bump.
this sucks trying to find why its not starting. you turn the key and the voltage just drops

 

[Alvin in AZ]

Wow 13 hours you ain't found it or fixed it?
I'm guessing you don't have a meter or a friend with a meter?
Did you happen to cook the insulation on that bundle of wires?

Alvin in AZ

 

[64-4x4]

Always good practice to unhook your battery when welding or use a surge protector that clamps onto the battery. know a couple guys who have torched computers on newer vehicles because they left the battery hooked up and had the ground clamp on the opposite end of the vehicle. Have heard of some funky things happening though. were did you have the ground clamp located? sometimes this will have weird effects on things.

 

[klatt_89]

I know when the exhaust was welded on my 99 F-150, they hadn't disconnected the batter, but most welding was done off the truck until the h pipe and connecting to stock pipes. Where was the ground at (as 64 asked), and did you look through the wires the smoke was coming from? I'm sure someone else may be able to give more input.

 

[countryboytn]

As for your issue, I wish I could help. I know what it's like when you have something like that, and can't figure it out. It can be frustrating. Hope you get it figured out, and back on the road.

 

[89PSD]

the ground was clamped right on the exhaust tubes. it was about parallel with the t case. Then every time i tryed to start it arcs were jumping from the mufflers to the flame?! (one muffler was very close to the frame from no hangers yet).

I did do a visual scan of the wires by removing all the wraps of electrical tape leading upto the computer. All the wires looked clean... no signs of burns.

 

[Alvin in AZ]

Meter time.

IMO, meter time starts the first instant of electrical problems, tho.

The trick with electrical problems is to not go messing around moving stuff.
The trick is to use the meter to find the trouble before you go clearing it up
by moving stuff around and so hiding the problem from yourself.

You don't have a meter or a friend with a meter? :/

http://www.oreillyauto.com/site/c/detail/DOR4/85593.oap?pt=N0221&ppt=C0371

Alvin in AZ

 

[64-4x4]

what do you mean sparks are jumping from the arc to the flame? or do you mean frame? if that was the case you must have had a bad ground. and thats when bad things happen to good people.

 

[Mil1ion]

The fusible link is located between the starter relay and the fuse box

I suspect you fried a fusible link

 

[klatt_89]

The fusible link is located between the starter relay and the fuse box

I suspect you fried a fusible link

That's a good point Mil1ion.

I was thinking if there is arcing from muffler to frame, frame being a ground, there is a positive charge going to the starter, but is being transferred through the metal to the muffler to the frame, as electricity likes taking the shortest route possible. At least if I'm thinking right, check the link he is describing, he knows what he's talking about.

 

[89PSD]

what does a fuse able link look like?
is the fuse box your talkin about the one under the dash?

 

[Bricks]

what does a fuse able link look like?

 

[64-4x4]

Yea i would start with the link they show above. Had one blow on a work truck once and it took us forever to figure it out! Random question, what type of welder were you using? Future reference if your welding and feel your ground clap is getting hot that means you have a bad ground.

 

[Fellro]

Had them get hot before, but the ground was fine, just running that long and high amp...

 

[Scoop531]

The fusible link is located between the starter relay and the fuse box

I suspect you fried a fusible link

 

[89PSD]

the welder was a 110v lincon electric mig. i found abunch of fuseable links by the battery that im going to check with a meter.

I did all my welds off the truck... took the exhaust off and on numerious times getting things right. then I came to the last weld i had todo. which I did on the truck.

 

[89PSD]

wow finally found the source of the problem. Dam EEC power relay went. bought a new one for $20 and started right up!! oh yea new exhaust sounds goooood.

 

[Alvin in AZ]

Your new relay will prob'ly work out real good for you and thanks for giving
us an update!

----------------

I've had trouble with Ford relays tho, even the ones from my 74k mile '91.
So simple age messes 'em up too? :/

Had both problems 1) not conducting when energized but have had -more-
trouble with them 2) conducing -as if they were energized- without being
energized! :/ No kidding, slam the door and the fuel pump would come on
and going to check the "TPS report " and find ~.75 volts there with the
key off and relay coil with no voltage on it.

This stuff was recommended on FSB...
http://www.parts-express.com/wizards/searchResults.cfm?searchFilter=relay 12 vdc
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=330-070
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=330-075
...read about it on FSB after thinking of swapping all my relays to Bosch.

Already used three Bosch relays in the '75 C700 ignition switch install...
http://www.panix.com/~alvinj/file12/BroncoDash.jpg
...could have done it with two easy enough but didn't.

For my kill-switch (anti-going-south-switch I insulated the starter-relay
from ground and so break the ground side of its coil-circuit through the kill
switch and also break the ground-side of two ignition switch relays that I
added at the same time.

Killing those relays doesn't effect the power windows or wipers. I moved
the feed wire for the power windows over to an always-on power source
so the windows can be operated without having to first turn the dangged
key on. What an irritation that was, not being able to roll up the windows
after stopping and shutting off the truck! :/ YMMV on that one, but I've
been doing it in-that-order since I was a kid so figured -it- needed to be
changed instead of me.

Alvin in AZ

 

[klatt_89]

Glad you found the problem! Now I need to do some modifications to the exhaust on my truck, haha