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Cowjock
11-27-2005, 11:19 AM
Hi All,

I am in need of some sound advice for welding a crack in a cast engine block. It's on a JD 2640 diesel tractor. I have already welded exaust manifolds with success but those could they could be replaced with out any trouble if I screwed up :eek: . The crack was caused by the replacement of the electric heater element. I had to heat the block to loosen the plug that held the element, really hated to do it but..... The crack is about a 1" long(yes it's leak coolent). What I'm figuring on doing is drilling a hole at the end of the crack then grinding small groove the length of the crack. Now, I have some of Hobarts Nickel 55 3/32 rods, are these the right rods to use? Suggestions? I know I have to preheat but what about post heating? I have an car engine block to practice on before I try it so I'm game for any suggestions.

I considered JB weld, NOT!!! Also considered Bars leak,I know it would work but I want it fixed permently.

I have a Hobart stickmate LX, a Miller mig machine and an old Lincoln generator/welder AC only(my favorite :) ). Been welding on farm equipment with tremendous success for the last 25 years, no formal training, but did have some help from a professional welder years ago.

Thanks,

Bill

hankj
11-27-2005, 01:15 PM
Bill,

I guess if you need the block heater, you're jockeyin' them cows in cold country. I think you have the right rod for the job. Preheat will probably be necessary. Just a brain fart: could you refill the block with pre-heated coolant after the weld is completed and start the engine? Once the temperature gauge came off the peg a little, you could shut er' down and let the engine's natural colling rate take care of the post heat?

Hank

Cowjock
11-27-2005, 05:39 PM
Thanks for the response. Even better, I can get the engine up to heat, remove the coolant, then heat it up some more with the torch. I know it won't take long to weld. Weld it, put the coolant back in while still hot, then start it, no problem keeping heat in it after it's running. Natural cool down, no problem.

Take a look at the picture Hank and let me know what you think.

Bill

Skooter
11-27-2005, 06:24 PM
You could braze weld it. It would be less risky and should fix the problem. I read is a book ages ago about 'Cold arc welding' with a stick welder. I saw a pic of it used to repair an enormous crack the length of a Cast Iron block in a tractor. I can't remember all the details but someone else may.

Andrew

SteeL_ButcheR45
11-27-2005, 06:35 PM
Being a retired heavy equipment mechanic I have welded cast iron blocks, heads etc. The filling of the engine block w/coolant and bring up to temp sounds good.....BUT...I have found that if there was liquid present before welding ( I know you are gonna drain the block before welding ) that welding tends to draw the liquid to the crack. Hence ya gonna have pin holes in your weld from the ever present leftover liquid...can I get an Amen :eek: :eek:

From the Cool and Dry, Dry, Dry Flatlands of Texas,
danny.......not tryin' to be a "know-it all" :o

wrenchbender
11-27-2005, 06:57 PM
Being a retired heavy equipment mechanic I have welded cast iron blocks, heads etc. The filling of the engine block w/coolant and bring up to temp sounds good.....BUT...I have found that if there was liquid present before welding ( I know you are gonna drain the block before welding ) that welding tends to draw the liquid to the crack. Hence ya gonna have pin holes in your weld from the ever present leftover liquid...can I get an Amen :eek: :eek:

From the Cool and Dry, Dry, Dry Flatlands of Texas,
danny.......not tryin' to be a "know-it all" :o

Oh yes an Amen is in order here. By all means keep it dry and clean nic 55 is a good choice I also like the nic 99 rods work realy good on blocks and heads trans cases.Repaired many of all the above through the years.

Cowjock
11-28-2005, 12:10 PM
Thats exactly what I was looking for: EXPERIENCE!!!! :D I'm glad I found this site. I learned the hard way about welding pipes or anything else with liquid in it. Didn't take long to learn it either. That's when I was young and dumb(teenage years).


I'll let you guys know how I make out with the repair, probably tackle that tomorrow.

Need some suggestions for a plasma cutter for farm repairs, 1/2" steel max.

Bill

I'm located in SE Pa. right out side of Phila.

lars66
11-28-2005, 08:36 PM
another amen.use air & blow nozzle to dry the crack up after the block is drained to try & avoid residue from heat evoporation of antifreeze ect. in the crack. the crack will olso have to be welded to the very edge of the hole or the coolant will follow the crack left on the inside machined surface to the outside.

coalsmoke
11-29-2005, 04:11 AM
Need some suggestions for a plasma cutter for farm repairs, 1/2" steel max.

Bill

Miller Spectrum series, really nice units. Go to www.millerwelds.com and check out their plasma cutters. (the Spectrum 625 should suit your needs quite nicely).

precisionworks
11-29-2005, 12:59 PM
IMO, the best way to weld a cracked block is to take the engine out of the machine :D

The next best way is to "cold weld" using a specialty electrode like Harris 94. Here's a quote from their booklet:

Harris 94 is superb for cladding, buildup and joining cast iron. Its fast freeze characteristics make it ideally suited for "cold welding" in all positions, even vertical and overhead. Use Harris 94 on thin-wall parts, housings, machine bases, motor blocks, etc.

Procedure: Use AC or DC, reverse or straight polarity, with a short arc. Prepare the weld area by cleaning and beveling. Use CHAMFER ARC for grooving. Tack weld cracks and drill small holes at each end of cracks to stop further cracking. While preheat should not be necessary, for ultimate machinability, preheat to approximately 400ºF. Stringer beads are preferred; however, slight weaving may be used. Skip or back-step weld. Short deposits no longer than 1 1/2" are recommended. Peen each bead while still hot to stress relieve. Allow casting to cool slowly.

The secret to this repair is to first U-groove the crack, all the way to the bottom (drain all coolant first). Don't Vee-grove - that acts like a wedge. Drill each end of the crack. Run short stringers along each side of the crack but not over the crack. You want to "butter" the walls of the U-groove. After each short pass, let the block cool until you can just touch it with your bare hand - about 200*F interpass temp, max.

--------------------------------------------------------------------------------------

UTP makes a similar electrode called UTP8 Softflow. Their "UTP Welding Guide" has a detailed description of the cold welding process, but their field reps can explain it even better. Any welding supply store that sells UTP will be happy to put you in contact with the field rep.
http://btwusa.com/html/support.html

It's really pretty easy - BUT - you cannot get in a hurry :D

DF5152
11-29-2005, 08:21 PM
dont know if it was mentioned but make sure u drill a small hole in the end of the crack or it will continue...

Skooter
11-29-2005, 10:28 PM
IMO, the best way to weld a cracked block is to take the engine out of the machine :D

The next best way is to "cold weld" using a specialty electrode like Harris 94. Here's a quote from their booklet:

Harris 94 is superb for cladding, buildup and joining cast iron. Its fast freeze characteristics make it ideally suited for "cold welding" in all positions, even vertical and overhead. Use Harris 94 on thin-wall parts, housings, machine bases, motor blocks, etc.

Procedure: Use AC or DC, reverse or straight polarity, with a short arc. Prepare the weld area by cleaning and beveling. Use CHAMFER ARC for grooving. Tack weld cracks and drill small holes at each end of cracks to stop further cracking. While preheat should not be necessary, for ultimate machinability, preheat to approximately 400ºF. Stringer beads are preferred; however, slight weaving may be used. Skip or back-step weld. Short deposits no longer than 1 1/2" are recommended. Peen each bead while still hot to stress relieve. Allow casting to cool slowly.

The secret to this repair is to first U-groove the crack, all the way to the bottom (drain all coolant first). Don't Vee-grove - that acts like a wedge. Drill each end of the crack. Run short stringers along each side of the crack but not over the crack. You want to "butter" the walls of the U-groove. After each short pass, let the block cool until you can just touch it with your bare hand - about 200*F interpass temp, max.

--------------------------------------------------------------------------------------

UTP makes a similar electrode called UTP8 Softflow. Their "UTP Welding Guide" has a detailed description of the cold welding process, but their field reps can explain it even better. Any welding supply store that sells UTP will be happy to put you in contact with the field rep.
http://btwusa.com/html/support.html

It's really pretty easy - BUT - you cannot get in a hurry :D

Thanks Barry. Thats what I was talking about. I'm glad someone else had heard of it. I was starting to think I was all wrong. :D
I've never had the need to use it so far. But Its useful knowledge to add to the repertoire.

Andrew

TOMWELDS
11-29-2005, 10:33 PM
I would groove it then weld it. I have a feeling you might have to weld a small scrap of metal over it. The piece that screws in has a taper and will try to open up the crack as you tighten it.

precisionworks
11-30-2005, 10:50 PM
Skooter -

Glad that you found that helpful. Repairing a cracked CI block is one of my favorites ... An average repair on a small crack will earn $300 to $500.

I try to quote a price before starting a job like this. Lots of farmers figure $50 to $100 is plenty. Which is about right if they take the engine out of the tractor & bring it to my shop :D

Skooter
11-30-2005, 11:39 PM
Skooter -

Glad that you found that helpful. Repairing a cracked CI block is one of my favorites ... An average repair on a small crack will earn $300 to $500.

I try to quote a price before starting a job like this. Lots of farmers figure $50 to $100 is plenty. Which is about right if they take the engine out of the tractor & bring it to my shop :D

Sweet. :D :D :D

I enjoy doing repairs. I don't get to do nearly as many as I'd like.
Man I hate doing quotes for jobs. Most things usually end up taking a bit longer than you plan. I think Murphy has something to do with it. :D

I had to build a pool hose box for a guy a few weeks ago. It was 3600x500x500mm (LxWxH). He wanted it to double as a bench seat with the lid down. About 30m of steel tube went into it. Then I put decking on the floor and the outside was skinned in plywood. After sanding and painting.. well a whole lot of work had gone into it. More than he was expecting. We nearly gave his wife a heart attack when we handed her the invoice :eek: . It was not at all cheap. But thats what you get when you order a custom made item.

Andrew

Cronatron Rep
12-01-2005, 10:25 PM
Sorry about the long post, but I have 4 or 5 heavy equipment companies using the below product for engine blocks and transfer cases.


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Unquestionably the final answer to the most difficult cast iron repair welding. This highly sophisticated
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IDENTIFICATION: Printed Electrode, TIG Flagged One End
APPLICATION: AC or DC Reverse Polarity
CRONACAST 211 SUPERIOR ADVANTAGES:
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• CRONAMIG 211 IS FULLY MACHINABLE AND HAS A HIGH ELONGATION
FACTOR WHICH POSITIVELY PREVENTS CRACKING
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TECHNICAL INFORMATION:
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BRINELL HARDNESS: 185-240
OPERATING PROCEDURES:
Use AC or DC reverse polarity. Generally, where a narrow, thin
bead is desired a straight polarity application is suggested.
APPLICATIONS:
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• SPROCKETS • CAST IRON TO STEEL
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• BEARING HOUSINGS • TRANSMISSION CASES
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CONFIDENTIAL MATERIAL, REPRODUCTION, IN WHOLE OR IN PART, PROHIBITED Printed in U.S.A. (Rev. 7/02)

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1/8
5/32
3/16
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120-150
140-175
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3/32 x 36
1/8 x 36
TECHNICAL INFORMATION
CRONATRON WELDING SYSTEMS, INC.
CRONACAST™ 211

CRONAMIG 211M-FC CRONATIG™ 211T
SIZES
CRONAMIG™ 211M-FC
.035 x 10 lbs.
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Corporate, Research & Distribution Hdqrs: 6510 Northpark Blvd. Charlotte, NC 28216-2367/800-843-0763/ www.cronatronwelding.com