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Massive Crack

Posted: Mon May 31, 2010 4:55 pm
by Ambidextarous
We've just found a five inch long crack on the side of the engine between the two core plugs. Is it possible to weld such a big crack and if so, where do you find somebody to do it. It's not your ordinary welding job, is it?

Posted: Mon May 31, 2010 5:28 pm
by Bensdexta
Sorry to hear that :(
You may be able to weld it, or metal stitching may be the permanent solution.
A quick google brought up these folks who weld cast iron:
http://www.castironweldingrepairs.co.uk ... epairs.php
All the best,

Posted: Mon May 31, 2010 5:37 pm
by Ambidextarous
Thanks for the quick reply Ben. It's just one thing after another with this tractor :(

Posted: Mon May 31, 2010 5:54 pm
by dexta roadless
hello
i have done this myself several times
i just use stainless steel welding pins. Weld 2cm and tap it with a very small hammer until it is cold enough to touch it with a finger, and then continue 2 more cm until the job is done. Prepare it by grinding a groove along the crack. It's not magic, just time consuming labour. You can also buy spesial welding pins ment for cast iron. Expencive but worth it.

Posted: Mon May 31, 2010 7:12 pm
by Ambidextarous
Thanks dexta roadless. Did you heat the block up first. I thought the area needing welding had to be pretty hot before you started.

Posted: Mon May 31, 2010 8:34 pm
by john.n
have you concidered using chemical metal? might be worth using after welding just to make the repair look tidy, and may fix any small pin holes that appear. someone had welded mine in the past but it weaped after adding strong antifreeze.

Posted: Mon May 31, 2010 10:35 pm
by dexta roadless
no it does not need to be heated
The whole cloue is that you dont weld more than 2 cm with minimum heat(amps on the welder) and keep tapping it until cold (almost lika a woodpeccer :lol: ) Then you will not get any tension in the steel structure.
hope this make sence :D
Of course use of chemical metal afterwards to seal it and refurbish the surface is possibel

Posted: Tue Jun 01, 2010 6:59 am
by pjjms
I agree with roadless. Small welds and tapping. The tapping is very important and has a suprising effect on the metal. We also use it on pressure vessels as it stops corrosion in the welds.

Posted: Tue Jun 01, 2010 8:08 pm
by Ambidextarous
Thanks everybody. The tractor's sixty miles away so it's not that easy to just nip out and do but i'll try to get some rods and go over at the week-end. I'll post the results.

Posted: Wed Jun 02, 2010 7:42 am
by Tubal Cain
Dextas for the UK market run with the cooling system at atmospheric pressure, i.e. unpressurised.

I have three or four engines here which run with cracked blocks, which is a common fault with the Fordson engines. The leakage is minimal provided that the crack hasn't opened up and can be controlled by using a proprietary block sealer. Try this site

http://www.vintagetractorspares.co.uk/v ... al-up.html

In your case I would be tempted to try to seal the block first rather than go to the trouble of trying to weld it. As regards resale value,
anyone who knows anything about Dextas will check to see if the block is cracked and welding it up will lower its value.

Gerald

Posted: Wed Jun 02, 2010 8:16 am
by russelm
I assume its sensible to drill a hole at each end of the crack to stop it spreading further first?

Posted: Wed Jun 02, 2010 9:00 pm
by Tubal Cain
Drilling a hole at the end of a crack is recommended in order to prevent the crack propagating. In this instance I would assume that the crack occured a long time ago and probably will not get any worse, if it does it will run into the bores for the core plugs.

So in view of the hassle involved to gain access to the crack I would tend to leave it as is, but keep an eye on it in case it is propagating.


Gerald

Posted: Sat Jun 05, 2010 6:58 pm
by Ambidextarous
I've ordered the engine seal jollop from Vintage Tractor Spares. Didn't expect them to be open today and the chap was really helpful. Thanks to Tubal Cain for that link :D

Posted: Sat Jun 05, 2010 7:04 pm
by john.n
make sure you give the cooling system a real good flush first. or the sealent will seal any dirt into the passage ways as well. i had a bit of an issue with my block drain tap after using k-seal i think it was.

Posted: Sat Jun 05, 2010 7:12 pm
by Ambidextarous
Very timely warning John.n, i hadn't thought about flushing the system.I suppose i'm so keen to get this b$$**? back in one piece and running that it's easy to miss the obvious.