Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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.

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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.

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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.

Re: Center Exhaust Port Crack
 

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.

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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.

Re: Center Exhaust Port Crack
 

That seems like a great solution.

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

This stuff?

Re: Center Exhaust Port Crack
 

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

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

Re: Center Exhaust Port Crack
 

I use it on regular basis and it does work...Seal-lock products been around in the engine rebuild buisness a long time.
Ronnie i get that you done this since the dinosaurs walked the earth but sometimes you come on like a bulldozer telling it´s your way or the highway...we all have an opinion based on the sum of our fuckups...
I´m just a small shop putting out an engine a month and only having 250 blocks on the shelf but i have tried any way i could come up with saving theese blocks during the years so usually what i state is based on what i do in real.

Re: Center Exhaust Port Crack
 

Sorry I come across a little strong but since I have been doing this for a number of decades already learned what will and wont work so I try to spread the word. Running the flathead all out was a steep learning curve {pushing over 4 times stock HP} that showed the weak points that needed attention. Cracks were a constant issue until I figured out how to stop it from happening. Repairing those cracks during the learning curve was important to save blocks with tons of work into them. So I tried pressure sealing also heated blocks per some sealer instructions found no magic solution only one that actually helped was the Sodium Silicate AKA water glass. Heck I even pined some cracks with the engine still in the car at the track and added the sealer as well some of my older race blocks have gone threw hell and back. Having fun doing it and will continue to as time goes on. Now next curve what happens to a flathead pushing 200 on the salt might find more issues to deal with time will tell.
Ronnieroadster ;)

Re: Center Exhaust Port Crack
 

Ron, do you have any problems with the water glass plugging the radiator? Do you leave it in the cooling system, or drain it out after sealing the leaks? Thanks, Allan

Re: Center Exhaust Port Crack
 

Alan I drain the mixture usually leaving it in no more than a couple of days. Never experienced any plugging of the radiator the mixture only plugs when it gets into a leaking area. Actually amazing how it finds the leak and plugs it. Heres an example. One time I had one of my race engines with cracks on the run stand. We use smaller hoses on the race engines lots smaller than the hose size used on the run stand. To solve the hose size issue I quickly put together a bunch of fittings that I knew would leak but figured it would be good enough for the short run time needed to circulate the water and sodium silicate mixture. As I expected the quickly thrown together fittings definitely had leaks however like magic once the circulating water was around 140 degrees the leaks stopped the sodium silicate sealed everything perfectly. But theres is one draw back to the leaking water mixture it will leave stains on painted surfaces but quickly cleaning up the spills will eliminate the staining.
Ronnieroadster

Re: Center Exhaust Port Crack
 

Thanks for the voice of first-hand experience! Too often people seem to just repeat what they think they heard from Uncle Joe's barber's third cousin's drinking buddy.

Re: Center Exhaust Port Crack
 

Another thing is when i build or repair a block for a customer i need it done before i even start assembling it...so can´t go ahead and build it with a leaking blocking hoping it will later seal up when i run it...
Or the crack is water to oil...
So there´s more then one aproach.
Ronnie i always like hearing real life first hand knowledge, to damn many magic fixes on internet not even close to working.