Cracked block questions (with pics)

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pbufton
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Cracked block questions (with pics)

Post by pbufton »

Hi all

had a closer look at the new-found crack in my block earlier on, and been looking online at various methods to repair it

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Seen the Lock n' Stitch method of repair on youtube, and am currently emailing them to see what is best to use in this instance.

One thing I need to know is the thickness of the block in that particular area? If anyone knows it would be invaluable

thanks

dexta roadless
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Re: Cracked block questions (with pics)

Post by dexta roadless »

I welded this part some years ago on a SD. I believe it was around 7-9 mm thick, but not certain :scratchhead: :scratchhead:
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pbufton
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Re: Cracked block questions (with pics)

Post by pbufton »

Thanks dexta roadless. Do you mind me asking how did you weld it?

russelm
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Re: Cracked block questions (with pics)

Post by russelm »

Mine also had the usual crack.

I drilled small holes at the end to stop the crack speading, then used a small thin cutting disc to open the hole out. This was filled with JB weld following cleaning and now all is good again.
Mark Russell - 1959 Standard Dexta - Work In Progress!

dexta roadless
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Re: Cracked block questions (with pics)

Post by dexta roadless »

Mine wasn't quite the same crack. It was an old damage after a frost. After grinding a groove I just welded with 1,2 mm stainless weldingrod with just about 40-50 amp power. welded about 2 cm and knock on it with a small pointed pick until it is so cold you can touch it with a finger, half to one minute. Then proseed with another 2 cm.
Time consuming, but works :roll:
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pbufton
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Re: Cracked block questions (with pics)

Post by pbufton »

i assume if it was only a small crack then only one bead of weld was needed...If I go for the welding route, i'd contemplate opening up the crack a bit with a grinder and either putting one heavy bead in or a single one in the bottom and a couple over the surface.

hmmmm

dexta roadless
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Re: Cracked block questions (with pics)

Post by dexta roadless »

the most important here is to avoid tensionsin the casting. If so it will crack beside the welding. therefor i used stainless because it is fairly soft and flexibel, besides it attaches good to the casting.
6o Dexta Roadless
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pbufton
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Re: Cracked block questions (with pics)

Post by pbufton »

Ordered a pack of 10 2mm stainless rods, should be with me sometime this week. Will post a few pics of the repair as I go, haven't done arc welding since college so could be an experience!

thanks for the input all :mrgreen:

wfillingham
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Re: Cracked block questions (with pics)

Post by wfillingham »

I had this with mine 10 years ago and I decided to just get another block for £50 and completely rebuild the engine... as it turned out the head was cracked as well so I got another secondhand one.

At the end of the day I suppose it depends how original you want to keep it... though given past experiences with cracked cylinder heads etc. I decided to at least be 100% sure it was perfect and just scrapped the block.

pbufton
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Re: Cracked block questions (with pics)

Post by pbufton »

I know what you're saying. The thing is, i forgot to take photos of the tractor in one piece so to send off the docs to get it registered, and read somewhere on here that it can make registering the tractor difficult if the non-original engine/block is used and the serial numbers/casting codes are from noticeably different years...

A Lock n' Stitch kit from the US is going to be over £250 not including the shipping. This would be a definate fix, but isn't cheap. Especially with christmas coming.

You say you got a block for £50, Agriline do the engine rebuild kits for £160, roughly i'd have a rebuilt engine for £210ish (not including shipping or machining)


Hmmmmm. Stumped again.

tom lad
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Re: Cracked block questions (with pics)

Post by tom lad »

hi

i'd try to weld it b4 i'd try another one / poss. better the devil u know ??

even if i had to pay a engineer.

if i remember correctly from collage dissimular rods ,for stick welding , will also weld stainless steel , i think they are stainless .
fairly :roll: easy to use .
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pbufton
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Re: Cracked block questions (with pics)

Post by pbufton »

decided to take a risk and welded it using 1.6mm stainless rods, on 65amps roughly. Welded 2cm at a time, tapped till cool, then went to another area which was old and did the same.

Had a bit of an issue with the crack reappearing next to the weld all the time, got it near enough in the end though. The result looked apalling to the eye, so i mixed up some JB weld and coated the whole area. Was in the shed 8am-10pm yesterday putting it all back together, made good progress too!

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