Twin turbocharged 350 Chevy project

October 2004. Welding

I know its going to involve allot of fabrication, so i though I would start by seeing if i can use a TIG welder - These are much neater when it comes to fine and detailed work such as pipepwork for headers etc. So first expense will be obtaining a Tig welder - doh.

This was my first go:


After a bit of searching we found this Miller Dialarc 250 HF with a water cooled torch lurking at the back of someone's workshop - its wearing its age (Circa 1982) well and looks like its had an easy life. However, it had been stood for many years unused - this doesn't do them any good.


After having it turned on for a few minutes it kept blowing the breaker and we could smell burning - the water cooler motor was seized solid. We also noticed that the high frequency circuit wasn't working. I removed all the covers and started looking for loose connections, there were plenty of them - many of the push on spade connectors simply crumbled in your hand. Also the main lead to the torch literally crumbled in my hand - its made from aluminium for some bizarre reason - it had just dissolved away.


The water pump was an easy fix, as suspected it had just gone rusty - so a good clean was all that was needed, although the motor is in a bad way because it was switched on for about 5 mins whilst seized.

After replacing some 20 spade terminals and a good study of the wiring diagram, I started looking at the HF transformer, the fault was apparent, the insulation had crumbled away and was short circuiting against the chassis.



Here's a demo of tig welding 15mm Copper water pipe: (don't ask me why, just seemed like fun)


Aluminum and Steel TIG Welding, Not perfect but getting better - Looks better in real life, camera flash makes it look worse! (Yer, right!)


And here's the pile of practice welds (A few weekends and a small bottle of gas later) before you go rushing out getting a welder and think you are going to be able to weld overnight: