Center Exhaust Port Crack

[jack orchard]

Anybody have any advice on the repair of this crack? This is the center exhaust port of an 8ba.

[19Fordy]

Would it be possible to "V" grind it, preheat and then weld with nickel rod?

[jack orchard]

A good man could. No good men around here. I don't think i could.

By the way, it is a very small leak. Takes over 2 hours to leak from 40 lbs to 5lbs.

[19Fordy]

Jack, If you have an arc welder I bet you could do it. Get an old piece of cast iron and practice. There's also lots of videos on how to do it. It's not as difficult as it may seem.
Peen with ball peen hammer to relieve stress as it cools down.
https://www.lincolnelectric.com/en-u...t/not+provided
and
http://www.thewelderswarehouse.com/b...ing-cast-iron/
and finally
https://www.youtube.com/watch?v=0IkpAsNDbOo

[Kurt in NJ]

I think it was already repaired, the coloring on the gasket surface looks like there is a ground flush weld, and a crack in the shape of the marker line would usually extend through the gasket surface

[Tim Ayers]

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I'm hoping Ronnie Roadster chimes in. He's used sodium silicate to seal cracks in blocks.

I know it works since he's raced with some of these blocks. Just not sure if it works for exhaust port cracks.

[KiWinUS]

Tim we have used sodium silicate for many years in race blocks & heads. It will destroy a radiator for long term use

[Tim Ayers]

Originally Posted by KiWinUS

Tim we have used sodium silicate for many years in race blocks & heads. It will destroy a radiator for long term use

Interesting. I didn't now that. Can you get it to "cure & coat" or is it always in a gel-type state?

Hey Tony, I didn't forget about that pan. Well, I kind of did. I'll email you tomorrow.

[jack orchard]

Originally Posted by Kurt in NJ

I think it was already repaired, the coloring on the gasket surface looks like there is a ground flush weld, and a crack in the shape of the marker line would usually extend through the gasket surface

No. It is an active crack, discovered with a pressure test and soapy water.
I marked it with a Sharpie because it is very hard to see.

[Ronnieroadster]

it would be best you try the welding first and as a back up I would also use sodium silicate for added protection. However the sodium silicate is not meant to be left in the cooling system for an extended period. Its simple to use just add it to straight water. It wont work correctly if antifreeze is in the system. It sets up into a glass coating in the crack at the location of any leaks the set up temp is 140 degrees. After a while just change the water and you will be fine. Like Tim wrote above I have had excellent success using it to seal some bad cracks in my all out race blocks. Sodium silicate is the same stuff used in just about all of the head gasket/engine block crack products sold in most auto parts stores {for a lot of money}in a diluted form. You can find it on ebay where a gallon will cost less than the auto parts store small bottles and your buying it undulated so it will work much better. I forgot to add a fancy name ceramic block sealer is simply sodium silicate diluted its not full strength also in the old days it was called water glass sold in most drug stores theres lots of uses for sodium silicate.
Ronnieroadster

[Charlie ny]

Yep that's the stuff farmers called WATER GLASS way back....
Charlie ny

[bobH]

Originally Posted by Charlie ny

Yep that's the stuff farmers called WATER GLASS way back....
Charlie ny

Yeah, and the last time I bought some, I sourced it at the local drug store.

[flatheadmurre]

There´s a much easier aproach for this kind of cracks then welding.
With pressureplates installed hook it up to a vacuum pump.
Apply seal-all to the crack...shut off vacuum still applying seal-all.
Heatcure with torch.
It bonds with the rust and makes a permanent repair.
You really want belt and suspenders...add ceramic blocksealer to coolant at startup.

[19Fordy]

That seems like a great solution.

[40 Deluxe]

Do you drill the ends of the crack when using this method?

[flatheadmurre]

No drilling just adding the sealant...works real well for thoose tiny cracks you cant reach to drill and pin.

[tubman]

This stuff?

[flatheadmurre]

https://goodson.com/collections/crac...polymer-sealer

[tubman]

I didn't think it could be that cheap and easy.

[Ronnieroadster]

Originally Posted by flatheadmurre

https://goodson.com/collections/crac...polymer-sealer

I tried that stuff its not worth the effort just more diluted product! The sodium silicate is a lot better and for less than halt that price for a gallon take a look.
Sodium Silicate 37.5% Type N - 1 Gallon Water Glass Auto Repair Head Gasket on Ebay for $22.99 a whole gallon

Ronnieroadster