Center Exhaust Port Crack

[flatheadmurre]

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

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.

 

[Ronnieroadster]

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.

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

 

[40 Deluxe]

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

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

 

[Ronnieroadster]

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

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

 

[40 Deluxe]

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

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.

 

[flatheadmurre]

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.