Hello,

I would like to replace and weld in part of the floor panel at the rear of my 914. I have a question to which I have not found an answer on the Internet. When I weld in the floor pan I have to completely remove the 2 plastic fuel lines (flow and return) from the tunnel or I can leave them in when welding the floor pan. I am specifically concerned with the risk of fire. The heat when welding sheet metal can cause the fuel lines to melt or the heat to make the lines so hot that what can happen. The engine and tank are still installed in the vehicle as normal. What about the engine and tank, can they be built in or do they have to be removed before I start welding.

The carpet, seats, seat back wall will of course be removed by me beforehand.

Pictures of the area


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Greetings Leon

My $.02: Since you're in there just replace them with the stainless steel lines. Otherwise, just wrap them really good in damp cloths.

yes please just replace the original fuel lines to Stainless steel. Not expensive and not hard to install them after you fix your floor.

Anything you can possibly burn, melt, or char should be removed

I would go as far as removing (backing out) that section of the wire harness, burning that would be a costly mistake.

Or cut.

As I learned on my 2002 when I sliced the wire harness in twain with a cutting wheel on my angle grinder while removing rusty metal prior to welding in new floor panels. Only took a blink of an eye to really ruin my day.

Zach

Hello,

What does it look like if I want to weld with a cored wire welder, there is less heat and can this process be used to weld the sheets?

Kind regards

Leon

Flux core MIG would be my absoute last resort. If your welder will support it, you want to use a shielding gas. If welder won't support anyting other than flux core, I'd seriously consider selling the machine you have a get a MIG that will support shielding gas.

Flux core disadvantages:
Mess. More spatter, more weld build up, harder to metal finish.
Heat -- MIG is a good process but flux core is notoriously hard to control on automotive sheet metal.
Flux core tends to weld hotter than gas. Be prepared to back the panels with copper to avoid easy burn though.

There are some really affortable, basic MIG units that support gas. Folks on this site have done some really amazing work with very basic machines.

NOTE: Be super careful not to cut the control cable tubes that are inside the tunnel. There are areas where the tubes are only 2-3 mm away from the floor pan.

I'd pull the engine. The rear edge of the floor pan to rear bulkhead is edge welded to seal out water. You're going to have a hard time doing that seam and the puddle welds along it with an engine in your way.

I'm using flux core on my 914 restore currently, mainly as i'm working outside where the wind would cause problems for gas. Agreed gas is better, cooler cleaner but flux core is do-able.

what i find works is, 0.8 mm wire, a welder than has ability to to set amps low (15-25 amps), good stich welding technic and of course your friend the grinder to correct where its not gone right.

Also for flux core the body is clamped to the negative terminal, positive to the gun - this reduces heat & splatter.