cracked block repair...how NOT to do it!!!

[Wolfman]

Your full of intel today, Marty.
Egg preservative .
Never heard of that one either.
I have an egg producer a couple of miles from my AO that has a production house with over 100,000 laying hens.
Sure would take a lot of "Water Glass" for all those eggs.
Nasty looking stuff. City folks might not go for that one. Military might ! Be better than powdered eggs !!
He has a really large refrigerator !

[artificer]

Didn't you get ether preserved eggs that smelled horrible, were a pasty green when cooked, while @ main base in SVN?

[Jerry Hudgens]

Many years ago, my daddy used to repair cast iron parts by brazing with an acetylene torch. I don't recall him trying to repair a block. I know he pre-heated the part and he cooled is slowly in sand (I think that is what I recall). He also set up old time torches to get as uniform heating as he could. He had developed his methods over the years and was pretty successful with smaller cast iron parts.

Just wondering; is it possible to repair a cracked block by brazing? Would brazing reduce the stresses on the block as compared to welding with say nickle rods?

Just curious

Jerry Hudgens

[Fabrizio]

Here is the result of brazing an early GPW block.....

[Joe Gopan]

One of the most delicate cracks on a Jeep block to weld us on the passenger side below the water jacket line. If not experienced on this type crack it will out run the welder as it races the length of the block. Best way is to pre heat the entire block in an oven.

[Wolfman]

I remember the green eggs, John.
Being a farm boy, I just could not bring myself to eat one. My first thought was, if I had a chicken that laid something like that, I would put it out of it's misery.
That is one ugly braze job. Fabrizio. Brazing to repair cracks was pretty common on old farm tractors and was quite successful. With the tractors, it was function, getting the tractor back in service and cost, not beauty that was important.
With old jeeps, looks are equally important.

[Ian Fawbert]

Thanks for this post. It has been very informative and given a lot of food for thought especially in repairing blocks which are needed/unobtainable/special to the vehicle.

The following repair strategy and story is not jeep related, however the principles (like your RR engine) are the same. It is a sad story, but one which will one day have a happier ending.

We have a 1930 Straight 8 Nash sedan. It is mums car, she and dad met our car club in the mid 70's. Mum has had this car, original and unrestored (except reupholstered and repaint) since the mid 70's and in 2011 we found a leak from the water jacket through the bore into #3. There was also a leak from the water jacket into the sump. Both caused by rust. There are only 3 of this model of cars running in Australia.

Dad and I agreed to strip it down, get a shop to do the repairs/machining and we would reassemble- OHV engine, but really no different to the jeep motor or dads Oldsmobile side valve 6 he had rebuilt himself. Mum and dad spent the summer of 2011 stripping it down and in early January 2012 dad took it to a reputable, cautious and friendly rebuilder 4 shops up from his place of work. They started and made good progress. He wanted it close to keep an eye on it as other recommended places ranged from 8-15 hours drive one way!

Dad then developed a GBM 4 brain tumour. He passed away in July 2012 aged 61, 5 months after diagnosis and 6 months after pulling the motor out of the Nash!!!! This is not a sob story (even though that is what I feel as I type), but thought it a pertinent part of the whole story!

We carry on in every sense...

The rebuilder, in consultation with dad before he got sick and then mum and myself spent along time researching options to repair the block. Resleeving was not an issue for the bore leak, but the water jacket into sump was a tricky one to fix based on its location inside the block and after many visits from various block repair specialists, it was deemed was not repairable by standard methods- welding was not an option after the analysis (X ray maybe?) of the surrounding block material revealed it to be too thin and the risk of blow through too great. Lock and pin again wouldnt work as material was too thin I was told.

A liquid solution was sought (in reading above posts, I guess kind of like the water glass or KM metal seal- which sounds good too) and after several months of cleaning the block and correspondence with an industrial chemist who specialised in metal bonding compounds, a substance was custom made. It is not solid once set, but retains it shape. High temp capable, capable of withstanding hot water and oil etc. Ive no idea what it was but it was a custom made item, partly due to the odd job it was doing, the location and many other variables considered.

It was tested on a scrap cast iron block for ability to stick and also a cracked head from a 60's car for a few months to watch what it did, how it behaved and then the head was tested in hot water/the cleaning tank etc to see what it did- the compound stuck even with mild cooling system levels of pressure applied.

White metal bearings poured, machining work was done, the block cleaned again and the compound added into the water jacket carefully (with the block on a peculiar angle to get the compound into it and to the hole. It was left to set.

The crank and it's shims were installed by the machinist and then the block was taken home for me to finish reassembly. I made a whopping big steel table to work on it... such a big (strong) table! Thats one for the grandkids, assuming we can lift it!

It has been slow since. Here we are 4 years after I bought it home and it is 3/4 assembled. The sheer size of the block (it is near on 1.5M long), 2 kids (5 and 2), a full time job and not always being able to get to work on it have all slowed me down.

My only worry is the longevity of the compound out of water though I don't believe it was required to be in water to work/be stable.

Anyway, long story short, seeing your idea of plating and sealing as an alternative is one I shall hold onto if the chemical solution doesn't work. These blocks dont grow on tree's! I am sure a plate could be fashioned or milled to fit over the crack and a similar method of attaching or fixing applied.

Cheers,
Ian.

[Joe Gopan]

It''s been a number of years, but I sent problem blocks and manifolds to "High Speed Salvage" in Islip New York, they used to advertise in Hemmings. A customer of mine sent a 1930's Hercules Cylinder Head (Flat Head) from an Ariens Fire Truck to them. The repair required cutting off the top surface and replacing with new cast iron.

[OldPappy]

Amazing work!

Thought I was going to have to tackle a cracked block, so read through this before I registered on the site.

I do have a running engine with a crack visible on the hump below the distributor. I was considering different possible approaches to a fix. Hadn't torn it down, so hadn't determined if any other cracks exist. I don't see an indication of any oil getting into the water, just the seepage below the distributor.

Then I stumbled upon a good engine with no cracks, so don't need to worry about it anymore, but fixing one like this is absolutely amazing to me, and far beyond my abilities, or anything I would even attempt.

[Chuck Lutz]

x2 on the Lock 'n Stitch repair.