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RobM
07-30-2007, 04:18 PM
any one know any thing about this? whats a good filler rod to use? I assume pre heating is mandatory... what is a good procedure? is it possible to do a quality repair on a cracked engine components?

80proZ
07-30-2007, 05:20 PM
I don't remember what the alloy is but they do sell a cast iron welding rod but i couldn't get it in less than a 50lb box and that was way more than i needed(fix the starter to block area).You can use a torch to preheat.heat it till its red then let it cool until the red is just gone and weld it.What components???
I would trust it with some stuff but not others.

toxicz28
07-30-2007, 05:35 PM
You need high nickel rods.
From what I've read, to do it right, you have to preheat the entire casting to 900*f, do the weld repair, and then "heat it down" gradually(24 hours).
It is possible to do a quality repair on engine components. About 13 years ago, there was a guy who welded two smallblocks together and it pushed 700hp. Here's a link for stick electrodes for cast iron.
https://weldingsupply.securesites.com/cgi-bin/einstein.pl?Next::23:UNDEF:OR:D::PD

Good luck with your repair.

RobM
07-30-2007, 06:13 PM
im thinking about block or head repair. nothing that rotates

pav8427
07-31-2007, 06:55 PM
The diesel rebuilder guys do all their welding with the casting 'glowing' hot. Pre-heated,welded hot and cooled down slowly.
Using gas and a cast rod that matches the parent material.
I would imagine if this was done to a block that it would have to be totally re-machined.
Depending on the casting it may be easier and cheaper to replace it.

Doug

62fairlane
08-07-2007, 07:07 AM
I have welded stuff cold with nickel rod.

just small short welds with lots of cooling time between to keep the heat affected zone small. welded up a windowed block and a broken starter ear.

currently I have been welding injector bungs into a head for a port EFI setup (intake part of the head on this motor)

Karch
08-07-2007, 10:08 PM
I have welded stuff cold with nickel rod.

just small short welds with lots of cooling time between to keep the heat affected zone small. welded up a windowed block and a broken starter ear.

currently I have been welding injector bungs into a head for a port EFI setup (intake part of the head on this motor)

FE seriese engine?

Mathius
08-14-2007, 03:59 PM
My local Sears Hardware carries cast iron arc rods, 3 for $5 I think they are, 1/8" rods.

Not too bad, to give it a shot.

They also carry aluminum rods, and aluminum flux coated rod for gas welding.

Mathius

ahowudoin
08-14-2007, 06:53 PM
You might try this http://www.henrod.com/index.htm

chassisguy
11-24-2007, 07:55 PM
The way i do it is drill a hole at the start and end of the crack

Then bevel the crack with a grinding wheel

Take MG stick rod and break the flux off and clean it with emery cloth

Then i TIG it with the welder on DC

It gives you plenty of control and you are garaunteed the crack is sealed as you watch it melt together!

blown71 nova
12-13-2007, 03:27 PM
pre heat it and gas weld it w/nirod been doing it for 35years

Travis Rankin
03-19-2008, 05:33 PM
Cast Iron is one one the coolest wierd metals I've learned to weld..

The best true "Cast Iron" weld is done with a torch, cast iron filler rod and a special cast iron flux.. You have to grind the area all clean, and prep it with a huge "V" groove then preheat it.. focusing on the edge to be welded.. you will see carbon burn out of it in the form of graphite.. then you slather it up with the flux, and weld it up with the filler metal.. its really wierd to weld, as you can't really see a heat color change through the goggles.. the flux sparkles as it melts, and the texture when welding is like a really thick paste..
Give it a nice slow post heat, chip off the flux and the end result is a perfect color and texture match cast iron repair.