Lincoln Electric IM666-A manual Work stud of each power source to

E-3	TROUBLESHOOTING	E-3
	Observe all Safety Guidelines detailed throughout this manual

PROBLEMS

(SYMPTOMS)

PPOSSIBLE

CAUSE

RECOMMENDED

COURSE OF ACTION

Porosity in the weld. (Continued)	g. Wrong shielding gas composition.	g. Make sure the shielding gas is appro-
		priate for the weld procedure.
	h. Lead arc length too short.	h. The lead arc should be in the spray or
		pulse mode and not in globular or
		short arc transfer.
	i. Water is leaking into the arc.	i. Verify that nozzle to torch o-rings are
		sealing properly.
	j. Air is being drafted through the barrel.	j. Check that the o-rings to seal the bar-
		rel to the over molded assembly are
		sealing properly.
	k. Weld is too large.	k. Use a trailing gas shield or a nozzle
		that supplies a wider coverage of gas
		shielding.
	l. Excessive anti-spatter fluid.	l. Use only a minimal amount of anti-
		spatter fluid.
	m. For installations with an anti-spatter	m. Verify that the solenoid closes com-
	system, the anti-spatter solenoid may	pletely.
	not be closing completely.
	n. For installations without an anti-spat-	n. Make sure the anti-spatter line is
	ter system, the line may not be	plugged and sealed.
	plugged.
The arc length is inconsistent.	a. The contact tip is worn.	a. The wire should slide freely through
		the contact tip. Replace if necessary.
	b. The liner and/or conduit are dirty or	b. Clean the liners and conduit. Replace
	worn.	if necessary.
	c. The drive rolls and guide tubes on the	c. Make sure the correct size drive rolls
	wire feeder are not properly assem-	and guide tubes are in the feeder the
	bled.	wire feeds through without distortion.
	d. The variation in the joint is too large.	d. Improve fixturing and part forming if
		necessary, or add seam tracking.
	e. The electrode or work lead connec-	e. Verify that all the connections are tight
	tions are loose.	and are not overheating.
	f. Only one ground lead is being used.	f. Use an individual ground lead from the
		work stud of each power source to the
		fixture.
	g. The wrong weld program has been	g. Make sure the welding program on the
	selected.	power source matches the wire size
		and gas actually being run.
There is arcing to the nozzle.	a. Spatter build-up is bridging between	a. Remove spatter build-up on a regular
	the nozzle and contact tips or diffusers	basis. Adjust weld procedure to
		reduce spatter.
	b. The nozzle is too narrow for the appli-	b. Switch to a wider nozzle.
	cation.
	c. The torch is not insulated from the fix-	c. Make sure the torch is on an insulated
	ture.	mount. Use M19190 insulator if neces-
		sary.
There is arcing between the contact tips	a. Spatter build-up is creating a bridge	a. Remove spatter build-up on a regular
or arc flaring.	between the contact tips.	basis. Adjust procedure to reduce
		spatter.
	b. The wire size selection is wrong.	b. Switch to a larger diameter lead and
		trail wire.

CAUTION

If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.

TANDEM MIG TORCH