Nasty surprise
 

After a recent engine change a most unwelcome water leak in the form of a crack in the block (Chev 6cyl.) became evident and no amount of choice language would make it disappear. Seriously, a metal stitching exercise will occur
in the near future using the US "Lockinstitch" product to repair the damage. Images attached. Can any knowledgeable member tell me what the wall thickness is in this area of the block? Thanks and regards.... Rod

I am spending too long on forums
 

G'day BSM,

I was only looking at the Stovebolt site for new things they have posted up and I found that someone has just faced the same issue that you are. They posted up a step by step description of what they did and also links to the manufacturer's page - go to this link

http://www.stovebolt.com/techtips/en...racked%20block

I hope it is of some help to you. :)

Kind Regards
Lionel

Mate, many thanks. Will check it out. Rod

Lionel I checked it out. Seems I am not going to avoid a test hole or 2 although another chap is going to check out an old block for me tomorrow. Following is a link to one of the Locknstitch training videos which was also very informative.
http://www.youtube.com/watch?v=Pq0wfU4ZaKk
Watch this space as they say!! Rod

I'd just groove it a bit with an angle grinder and use JB Weld on it.

Been there, done that ....
 

My Chevrolet 1.5 ton had a crack like that, so I called in the Metallock site chap and he fixed it on site, in the truck.

but ...


First thing he did was clean the surface of the block and do a dye penetrant check, which revealed the crack went from than location ALL the way back to the bell housing. To be fair he just chased it down and fixed it - worked perfectly afterwards and didn't leak

Apparently this is at a change of section thickness and a known weak point. Since yours is bleeding through the paint I'd suggest that the crack may be longer - strip back the paint along the same line each end of the crack.

Get it fixed on site, by a professional, them just forget it, but do check your oil in case the water is going in, as well as out.

Had a look
 

The US product looks fine for filling and sealing a crack, but the repair method tends to push the sides of the crack apart - possibly elongating the crack.

Here in the humble old UK the Metalock people...

http://www.metalock.co.uk/Typical_On...n_Repairs.aspx

...do it differently. They use formers to drill ACROSS the crack at intervals and drive in a tapered dog-bone type of insert which pulls the sides of the crack together, and then they use pins like the US ones to seal along it. This is a much more satisfactory system from a mechanical point of view.

I can see you are in Australia, a fair distance from them, but I'd recommend them highly if they had a local agent, though these days it is probably an arm-and-a-leg job for a site visit. I was more than happy but then it was twenty years ago.

Very clever. I've always thought a cracked cast iron piece was irreparable. Obviously not.

I agree David JB weld works well as long as the surface is cleaned well.

I saw an old John Deere 2 cylinder tractor that had a wrist pin slip and groove the cylinder. The old farmer filled the groove with JB Weld then honed the cylinder. It had been used for several years when I saw it apart and you could tell where the JB was but it was still holding up.

I am currently rebuilding a Wilson pre-selective gearbox for a 1934 Riley and the car had a rod through the side of the block. The owner of the car had it laser welded were the company specialised in this repair work first cut a piece out of an irreparable block and laser welded that in the "good" block. First time I have heard of this technique. Not cheap but as these blocks are hard to find he had no other option.

Cheers,

Thanks for all of the above input once again. After demystifying the problem to be tackled the Locknstitch bits were purchased from a very helpful agent in Mackay (QLD-Aust.) and the work began. Few images attached for those interested. You were correct Gordon. After removing more paint the problem grew to approx 4inchs. Some magnaflux chemical was purchased and after a few trys (alias learning curve) I finally got a result. Turns out it helped to remove the normally rough skin surface in the vicinity of the crack. First pic is the result. This was followed with a centre punch to make it more pronounced.
The other images show a few of the steps with the last being the end result. Pin edges can be peined or done with a 2mm pin punch which was the final choice. Engine now back in as of yesterday and all being well the leak will be a thing of the past. Rod

Last image. Generally speaking the task was relatively straight forward once you got the hang of it. Rod

Looks like you got it
 

I'm glad you chased the ends of it before you started the repair.

That's a pretty typical crack through the thin casting section between two webs. Here in the UK it would have been caused by freezing - not sure if that is likely where you are.

Have a really good look at the other thin sections before you put all the other bits back on.

Nice work Rod! :salute:

Good work Rod! My 1940 Chev engine developed almost the same cracks but in two places back in 1995 on the 1st day of "Back to the Track" in Alice Springs, when the temperature dropped to Minus 8 over night and being in the centre of Australia, I did not have any anti-freeze in the cooling system.

The short term answer was a product called 'Irontite' (sic) which sealed the crack with a form of rust.

That engine is still ok and hasn't leaked yet.

Regards Rick.

Yes Gordon, to the diehard or experienced restorer of such things, said problems are not unusual I imagine but to some of us 'hobby' enthusiasts these mechanical setbacks do certainly add to the learning curve. Having recently completed some research on WW1 Lorry operations In Europe I am reasonably familiar about the somewhat extraordinary lengths they went to to prevent "frost damage" etc. and now one is fast coming up to steam re WW2 it seems. Your comment re the "thin" sections is noted. Just under 6mm was the guestimation for this area so one was careful not to strip the tapped holes when adding the special pins. Will certainly check as best possible before the bits are put back on. Thanks to the others for their words of support and yes Rick, after a good cooling system flush an amount of Chemi Weld will be added.
There is a bit of history re the engine/s. After securing the C60S cab chassis form the Hughes collection the engine was removed during the dismantling back to chassis. A donated 1948 Chev car engine (with smaller clutch) accepted the truck bell housing so it was temporarily installed to move the beast while the initial engine received some attention from a chap who was better skilled in matters mechanical. Long story short we were given another truck engine which has been re-engineered to take slipper bearings etc. All of the top end was dismantled and thoroughly checked however (and as we now know) the block wasn't. In amongst all of this we have had 2 complete engine/clutch/gearbox assemblies plus other bits including a cab donated to the cause which should arrive in a few weeks compliments of a generous benefactor. Another project will probably be considered in the near future. Busy times. Rod