Pressure-Sealing Blocks

[tubman]

Originally Posted by marko39

yes, devcon is a great epoxy that hardens like steel. i used it to repair leak in the bottom of my old air compressor tank (rust) holds well even at 175 psi.

Yikes! I guess that proves that DevCon is probably as good as people say it is, but using it that way can be very dangerous. Have you ever seen a picture of an air compressor tank that exploded? They let go along weakened seams. The rust has probably weakened the bottom your air tank, and there is a good chance the whole thing might let go. I had the same problem with mine, and formed a piece if 1/8 steel to the entire bottom on the tank about 4" wide and stick-welded it to the bottom of the tank. That was about 20 years ago and it's still holding. I still worry about it, but with my air distribution system, I'm nowhere near it, so if it does go, it probably won't kill me.

[1952henry]

Another epoxy choice...
https://www.belzona.com/en/products/1000/1111.aspx

[40 Deluxe]

A problem with a crack in the valley is the oil that has seeped into the crack as well as soaked into the cast iron itself.

[Tim Ayers]

Originally Posted by 40 Deluxe

A problem with a crack in the valley is the oil that has seeped into the crack as well as soaked into the cast iron itself.

Yes. It would need to cleaned again before repaired.

[Ol' Ron]

Many years ago I found a crack in the valley, it was quite long (4"). The block was a miled rebuild and the customer didn't want to spend much money on it so I drilled both ends, (yes it's quite thin), ground it clean grove it with the Dreml and used JB weld over the area including the two screws I put in it.. I think it's still running.
Moroso sells a ceramic stop leak, might fix some of these.

[Karl Wolf]

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In the mid 1970's,
I worked in an automotive machine shop.
There was a fixture for doing pressure checking, made by Irontite
As an adendum, there was a provision for curculating heated Irontites "ceramic motor seal" through the head being checked.
It didn't get used a lot- I don't remember what the cost was.

Karl

[tubman]

I thought the Belzona video about repairing a crack in a block to be quite interesting.

[Tim Ayers]

Originally Posted by Ol' Ron

Many years ago I found a crack in the valley, it was quite long (4"). The block was a miled rebuild and the customer didn't want to spend much money on it so I drilled both ends, (yes it's quite thin), ground it clean grove it with the Dreml and used JB weld over the area including the two screws I put in it.. I think it's still running.
Moroso sells a ceramic stop leak, might fix some of these.

OK, thanks. It almost looks like a casting flaw that finally let go. I’ll post a picture of the area soon.

[1952henry]

Originally Posted by tubman

I thought the Belzona video about repairing a crack in a block to be quite interesting.

I have no experience with it myself. I know they used it at work for heavy equipment, including leveling a floor under the drag transmission on one of the draglines.

[51woodie]

I have used different Devcon products over the years, depending on the application. Most industrial supply stores stock it (at least in Canada), and the products are available in various sizes. Here is a link that will get you in the general direction, but a call to their tech support, is often the best way to get the stuff that will work best for what you are doing.


https://itwperformancepolymers.com/products/devcon

[philipswanson]

Originally Posted by tubman

I have heard that there is something called "DevCon" that is like JB weld on steroids. I have never had an occasion to use it, but I think "Ol' Ron" has. Perhaps he will chime in on this.

I have used Devcon extensively but never on a block. Great for repairing splines and other structural repairs. I used it on the floor of my 40 in seams.

[philipswanson]

I would be leery of putting a coating in the water jackets. Would inhibit heat transfer to the water and act as an insulation.

[Ronnieroadster]

Originally Posted by philipswanson

I would be leery of putting a coating in the water jackets. Would inhibit heat transfer to the water and act as an insulation.

Theres no way to get to the area from the water jacket the repair would be on the block surface in the lifter valley area. The years of oil into the pours of the casting can be dealt with by pulling a vacuum from the water jacket not easy but also not impossible and then spray into the flaw with a good quality cleaner to remove the oil. Like old Ron wrote that are of the block is very thin theres no material for pinning. However its possible to be tig welded with a lot of care its best to experiment welding on an old junk block first. Many years ago i repaired a similar area with leak issues with just good old JB weld and as other have seen its still holding perfectly on a non stock hot rodded flathead.
Ronnieroadster

[philipswanson]

Originally Posted by Ronnieroadster

Theres no way to get to the area from the water jacket the repair would be on the block surface in the lifter valley area. The years of oil into the pours of the casting can be dealt with by pulling a vacuum from the water jacket not easy but also not impossible and then spray into the flaw with a good quality cleaner to remove the oil. Like old Ron wrote that are of the block is very thin theres no material for pinning. However its possible to be tig welded with a lot of care its best to experiment welding on an old junk block first. Many years ago i repaired a similar area with leak issues with just good old JB weld and as other have seen its still holding perfectly on a non stock hot rodded flathead.
Ronnieroadster

I wasn't speaking of a valley repair or any repair. I was referring to the process of pressure sealing locks in general. Not for a repair process but eliminating corrosion.

[russcc]

I had a small pinhole in one cylinder just above the bottom position of the piston in a 59 block that showed up in pressure testing after boring. I called Mike Herman and asked him if he used Irontite Ceramic Motor Seal, and would it seal that pinhole. He said that Irontite was the process they use, but it will not work in the combustion chamber. I called Irontite and the engineer said the same thing, the can't guarantee a seal in the combustion chamber.
This is the product. Irontite makes the pin and kits for pinning blocks.

[Yoyodyne]

I called Irontite and the engineer said the same thing, the can't guarantee a seal in the combustion chamber.

Does that mean it won't work in your case, because the cylinder is exposed to combustion?
How did you fix your block?

[40 Deluxe]

Originally Posted by Yoyodyne

Does that mean it won't work in your case, because the cylinder is exposed to combustion?
How did you fix your block?

As long as the pinhole is below the top ring, it's not in the combustion chamber.

[Tim Ayers]

Here is a picture of the crack in the valley on the 59AB.

[cmbrucew]

Tim


That looks like one for Ole Ron's repair.


Bruce

[russcc]

The pinhole was in the combustion chamber. We bored & sleeved it. Got the NOS sleeve from Fred at SSO. Worked great. The shop used some type of sealant between the sleeve and block. Same stuff they use on valve seats.