I have a spare engine and transmission I purchased for $50 last Sept. My son and I are using it as a father son project to learn more about Model T engines, and use it in our 1923 Touring. I tested the head and block with Magnaflux spotcheck, the head is fine, found this crack in the block. It's in #4 cylinder to the head bolt. I'm looking for an economical way to repair this. I haven't taken the crank out yet, currently it turns very well, and plan on checking it for cracks.
If the bearings are ok, possibly new rings and valve job. The engine in our 23 touring is running great at the moment and will eventually need at least a valve job. Our thoughts are to rebuild this spare engine and transmission with minimal cost as possible. Then next winter pull out the original engine, rebuild it along with the original transmission over time, while running the car with this spare engine and transmission. As long as this spare setup runs ok, leave it in place and use it, only putting back in the original setup if and when the spare setup gives us issues?
Thanks in advance for any help and suggestions, we purchased the families first model t, last sept and have been enjoying the journey of working and learning so far.
Joe, from the looks of the deck and the bore of that cylinder, you are looking at a rebore, a clean-up of the deck and a new set of oversize pistons. There will be better blocks out there for a mid 20's motor.
That said, if that is the worst crack, it would be easily fixed by having a sleeve fitted in that cylinder. A helicoil to the bolt hole would be all that is needed. With those two operations, the crack needs no other attention.
Others will have differing opinions.
Allan from down under.
Lock Stitch makes a blind threaded insert that will fix that. The tooling to install is not cheap. Maybe someone near you does it, check auto/truck machine shops. Another block may be cheaper. I do this repair.
Here is a link http://castingrepair.locknstitch.com/category/full-torque-products
I suspect you could get by with installing a solid thread insert in the bolt hole and be done with it. The benefit of a solid insert vs helicoil is with a solid insert there is less pressure on the threads from the head bolt tending to force the crack to spread. I personally wouldn't do anything about the crack inside the cylinder wall. Just make sure there is no edge to catch the top ring. Of course the proper way to do the job is sleeving. But since you stated you don't plan on running the engine much and don't want to do an expensive repair, I think you'll be fine as I suggest.
I would use a threaded thin wall insert like those available from McMaster Carr. I used the thin wall inserts in all the head bolt holes in my 1913 block.....They work great. Personally, I like thin wall inserts much more compared to helicoil style thread savers. Helicoil requires special drill/taps and installation tools.
I see Mc Master Carr offers the Lock N Stitch solid inserts. Like Les, I've used thin wall solid inserts to repair virtually all the bolt holes in a 1910 block with good success. For crack repair like what you have, I might opt for the Lock N Stitch product if I could justify the price of the tooling. If not, I'd go with the thin wall inserts.
While this block can be repaired another alternative would be to find another block. Dave Huson in Colorado may have a block. He had quite a few he was offering for sale at one time for PU only for 50.00 each. It depends what you want to spend and how much. I also have a block that had new Babbitt put in it and later developed a crack between a valve and a cylinder wall. I kept the block but later decided to find another good block.
If you found another block you could remove the serial no. off your cracked block and stamp it on your good replacement block and all would be good.
I had the serial# pad surfaced and restamped my block in a Model A. Worked out great and looks good. My old block cracked by a main cap.jmho
Assuming no leakage to the water jacket: Sleeve the bore and heli-coil the threaded hole.
I can vouch for Dave Huson. I've acquired two blocks from him and have looked at the PILE of blocks he has left. He's always getting more with estate purchases he makes.
BUT, it's a long way from Nampa to Longmont AND back. Totally doable though.
If the engine isn't being rebuilt, I wouldn't worry much about that crack until you do rebuild it.
So many people will tell you that it's 'oh so bad' but it's only bad if it's giving you a problem.
You can sleeve it when you rebuild it. If it bothers you now, helicoil might be just what you need.
Spray weld the crack and sleeve it.
You might be able to install a Keensert or similar thread insert and file it flush with the block. There may or may not be enough meat there for this.
Or, you could sleeve the cylinder.
Or you could play like you never saw it and use as is.
If you don't want to sleeve it and you don't want to leave it, you could grind a trench, following the crack and just fill in with weld. Then bore your cylinders. Surprised that no one else suggested this; must be a bad idea coming from me.
Forgot to mention the obvious, preheat the cast iron.
Thanks everyone for you all the various idea's and suggestions. When I find the time, I will take out the pistons and crank. Test the rest of the block, then determine the avenue I will take on repair or replacing the block.
I know people who had welding cracks like that and file the cylinder round again.
People tell me it can't be true. But it is, and it didn't even crack again later.