New tbi crate motor issues

[Jurt]

Hey guys.

I just finished swapping a new gm tbi crate motor into my 1994 k1500. I put an rv cam, lifters, roller rockers and a performer intake.
I roughly set the timing to 0 degrees at tdc and disconnected the timing advance wire, I just fired it up to perform the break in process of the cam. I think it went well, but this was my first time doing it.

I had coolant leaking out of my cap, so i shut the truck off after breaking in to put a different cap on before attempting to time the motor. When i tried to crank it again it sounded very labored and almost like the starter was stalling. (I installed a new started when i did the swap). When i got out of the truck the ground strap from the back of the passenger cylinder head to the firewall had a flame coming off of it, i think it must have heated up and touched a near by wire sleeve causing it to light up.

Any ideas on why this would be happening? Is it shorting somewhere causing lots of current to flow on the ground and heating it up? Please let me knowif you have any ideas!

Thanks
Jarrett

 

[Rusty Nail]

The ground strap caught fire WHILE CRANKING? Yes?

You've just got a loose connection involved somewhere. Likely a battery cable.
Check your connections at the battery and starter.

 

[Jurt]

Well it wasn't cranking normally. It was as if it straining to start it and then stalling or locking up the starter. Could that all be from a loose connection? I will take a look and see what I can find.
Thanks.

 

[skylark]

You definitely have a ground problem. The battery cable should go from the battery tto the front of the block down by the balancer. The cable should have a 10-12 gauge wire that bolt to the fender. The woven strap that you burned up goes from the back of the passenger side head to the frame.

My guess is that your battery cable got bolted to the frame. The reason for the fire and the slow cranking is that the strap isn't intended to have that much of a draw through it. The slow cranking is because of high resistance through the melting ground strap.

 

[Jurt]

You are 100% correct. My cable is bolted to my frame. I had a friend help me putting the truck back together, and I wasn't paying attention to where he put it. I'll have to get a new ground strap and move the battery ground to the block. Any idea if this would have wrecked anything else? Or just the ground strap?
Thanks!

 

[Jurt]

well i fixed the battery ground and replaced the braided ground. Fired up and was able to time it! Thanks!

 

[Rusty Nail]

I'm curious Skylark, is that experience talkin?

 

[skylark]

Nope. I just have swapped a buch of engines and I could see it as an easy mistake. Look up the "big 3" upgrade when you get a chance.

 

[DRAGGIN95]

Yes like mentioned, go ahead and do the big 3 and be done with it.

 

[slowburb]

Man, you're lucky you still have a truck, and a garage (if the truck was in one when it lit up). With a different course of events leading up to this (fuel/trans fluid leak on the firewall), it could have been a LOT worse. Glad you're OK.