I have a spare engine that I started to go through and once I sandblasted the block it looks like there are two cracks in the water jacket, one on each side of the inlet connection. Does anyone else agree it is a crack? I do not want to put any time and money into this if its cracked, too many good blocks out there collecting dust and rust.
Water jacket cracks are pretty common. Can be stitched or repaired with a cold weld.
Looks like it but magnaflux to verify.
A common place for "freeze cracks" to form. Many of them are much worse than that.
Don't junk the block. Easily patched, and any decent pre-generator block should be preserved.
I can understand not spending big money on a full rebuild of a cracked '18 block at this time. But not many years ago, some people were still junking brass era blocks because of minor cracks like that. Now those sell for a couple hundred dollars. More and more people are now putting proper engines into their '17 and '18 Ts. Even those blocks are getting more scarce.
If the main bearings are good? A simple rework can make a very nice engine out of that for just a relatively few dollars.
Just my opinion.
Main bearings are good, still had some shims. Initially looked like an easy freshen up and get running. The more I got into it the more a full rebuild seemed the way to go. But now with the cracks, looks like it will be a parts donor.
I've been running my '13 with a similar crack there and in the front. Patched with shim stock, JB Weld and Right Stuff. Weeps a little after cooling, but still going strong. Put over 3,000 miles on it since acquiring it. Patch it and go!
If it was a runner, I would agree, some rtv slathered over the cracks. But money in a rebuild to bore the cylinders, ream for new valves and lifters, new pistons and rings, grind the crank for new con rods, gaskets, etc., and I do not even have a 1918 project to put the engine in.
Yes, cracked. My roadster engine has been like that forever. Every few years it weeps a bit, but never makes a puddle. I just leave it alone.
Very easily welded with cast iron welding rod. Grind into the crack so there is a place for the weld. Pre-heat it to 250 deg or about and weld it up. Sand any standing weld off so it is smooth with the block, and needle the holly crap out of it, with a needle scaler. This will expand the metal and keep it from cracking and it will match the sand casting. This all has to be done seamlessly with the block still very hot when your done. With some paint, you will never see the repair. The last one that I did was a stitch repair that had fallen out, so the crack was now a 1/4 slot through the block from the water jacket to the back of the engine. The engine was complete when I welded it.
A small freeze crack like shown is easily fixed so it won't leak by cleaning and applying some Ultra Black in the crack and for added protection a piece of thin shim stock over it. I apply a second coat over the patch, job done. My first repair attempt was JB weld but I believe the expansion from hot to cold caused it to leak. the Permatex is flexable so it isn't bothered. If the surface is clean it will adhere very well also.
defiantly freeze cracks ...but as many have stated , this is easily fixed and if the rest if the engine is serviceable then this is still a good candidate for rebuild and regular use … in addition to welding or plugging the crack or the various compounds that tend to make an ugly repair , there are several " modern " compounds that will "wick" into cracks or porosity … these will also effect a good long tern repair with little more needed than a good cleaning of the repair area … Loctite makes a weld porosity filler that I have used with success … don't remember the material number , but a welding supply store should have that info.
as stated earlier , a block older than mid 20's is getting to be difficult to find in some areas … someone may need exactly this block … always an optimist gene french
Thanks everyone for the advice. As of now I will not be scraping the block but will not doing a rebuild at this time.
This is typical crack on Model T as I have same example of before and after metal stitching in pictures.
These can be repaired permanently.
I would thoroughly check other side as well as this was caused by block freezing.
easy,just v it out sandblast to get rid of carbein on the surface, then solder with asid core solder.then smooth it down them use 36 grit sandpaper and a hammer to put the cast look back on.i told you it was easy ha,ha. done lots of them.even the frt of the open valve blocks
I have a cracked block with rvt on it no issues, so far!!
Jeff, just out of curiosity, Is that block a starter block or pre-starter. ?? Aug 14 1918 seems to me like it could be a very early 1919 model year engine. Im not sure when the 1919 model year started. Im not at my books right now, so does anyone know when the model year started. My speedster project is being built as a 1919 so I may be interested in your block if you decide to sell it and it is a starter block.
I had a cast iron piece on a potbellied wood stove that had a clean break. I V'd it out,arc welded it with nickel rod without any preheating and after hundreds of times from fire hot to cold it never cracked.
Non starter block.
Sorry, should have written pre starter block.
Thanks Jeff. Without my books, I could not remember when the starter blocks started. Im of the school that any Model T block should be saved. The next generation of T restorers will appreciate it. Those cracks are an easy repair. I need a 1919 starter block, but someone will love to have this non starter block..... have fun and be safe ...