Hole in block??

Hey folks,
Guy has a tractor like mine that he bought not running with a hole on the block from a thrown rod. These motors are getting harder and harder to come by here in Germany, and this guy is on an island south of Italy so no motors available. If he got needed parts to repair the thrown rod, and the only problem left was the hole in the block, could it be repaired by tacking (or using screws) a plate over it and sealing with silicone or epoxy? This is the hole (pic). It is right beside the starter. Diesel motor if it makes a difference.

Thanks for any tips.

Dave

Dave A patch may be in order,Welding with :MUGGY Welding" could be done after a patch was fitted.
Worth a shot if cheap enough. Cantankerous
LOU.

I've had good luck using a piece of donor cast from something, anything really. I keep assorted brake drums, gear boxes, intake manifolds, etc for that. When the block is disassembled for overhauling and before it goes to the acid tank and machine shop I've preheated the whole thing, then weld with 99 pct nickel. Then peen like theres no tomorrow. Its worked really well in placed like this that dont have a stress load on them. Other places I'm about half and half.

Dave
If there are no cracks running out from the hole you could put a plate over it if your not worried about looks,seal with Permatex,hardening or non hardening,your choice. Have seen a few done this way.
You can drill and tap for 1/4" capscrews. Welding would be the best fix if you are knowledgeable in the proceedure.

I ran a VW engine with an epoxy patch about that size for quite a few years. Held up just fine. The trick seemed to be cleaning and prepping the hole and using an epoxy meant for the repair. Been too many years now to recall exactly what I used and I am sure there are better products now but what I used at the time was a Devcon metal repair filler epoxy. I recall we laid the block so the hole was vertical,made a plastic backer and taped it to the inside, then filled the hole. Left it cure an entire day then reassembled.
Good luck!

I am curious about your remark on peening. Does this have something to do with preventing the cast iron from cracking after welding? If so, do you know why it works? Thanks.

If welding is the repair of choice I would recommend a line honing operation on the main saddles as heat will pull the block and working with oil clearances of only a couple thousanths the block would not have to distort much to destroy the oil clearance. I had a customer that had a six cylinder Case block repaired near the 4th main and it did not run long after till it broke a crank right near the welded area of the block. Take this advice for what it is worth. mEl

I would fashion a patch slightly larger than the hole from some heavy sheet metal. Clean the area around the hole of oil. Roughen the area and clean one last time with toluene. Also clean and roughen the patch. Mix a two part epoxy like J B Weld or Devco and apply the the edge of the patch and the block where the patch will set. Apply the patch and let the epoxy set for 24 hours. Then clean the outside of the patch and cover the whole area with the two part epoxy. The hardest place to seal, from the look of the picture will be the right angle area where the block bolts to the torque tube.
Look at it this way. It is already broken. You can not hurt it trying to fix it. If it does not work, you might at least learn something.

Kent

In that location I would use a thin metal patch, maybe 20 gage, bent to fit, screwed fast using gasket maker. No real pressure. A fellow up my way run an Oliver 66 a coupla years with just a rag stuffed in the hole. They pulled the rod and piston and didn't replace it. Last I knew it would still pull a rotary cutter.

I know of a 4020 that was patched with a piece of heavy aluminum that was bolted fast that is still going strong after 40 years.

I had a 67 Chrysler with a 440 engine that broke a rod at 83,000 miles. Put a hole in both sides of the block, but nothing in the water jacket. I made up piecies of broken cast iron & ground to fit the holes. I welded it up with nickol rods & drove it another 80,000 miles. It sat for a few years until I sold it & it is still running.

The two metals expand and contract at different rates. Cast iron has good compression strength, but not much tensile strength. (pulling apart strength) When they're welded (molten and then cool, the nickel rod (fillermetal) will contract and actually pull away from the parent metal so, if you take a 16 ounce ball peen hammer, using the ball end and ding the new hot weld for one or two minutes after welding a maximum of about one inch (less if you hear a "tink" or crack, you will relieve those stresses set up by the welding then...wait till you can lay your hand continuously on the weld...run another weld 3/4 to 1" long and peen again till weld is done. If it is a crack that you're welding, you should drill a 1/8" hole all the way through at the very end of the crack to determine the thickness of the parent metal so you will know just how thick to vee the crack before welding about 3/4 of the way through) The hole will stop you from chasing the crack further and you can fill in the 1/8" hole with the welding rod. Clean real well after each weld, very important. Cleanlines is next to Godliness here. If you have pinholes in the weld, grind them out and do the weld over again. ohfred

Over peening does the exact opposite of what you're trying to accomplish and actually puts more stress into the piece than the welding. You also don't need the biggest ball peen hammer you can find to beat the crap out of it. Brazing would be a good option for that repair but needs a lot of preheat as well. Dave

Very good point and one that I should have been clear on. I dont even own a ball peen hammer bigger than 16 ounces and for stress relief on something like this I like a little 6 ounce one, using nothing but the wrist, but for a good long while.

You need to peen when the piece is still pretty hot to relief the shrinkage forces. After about 20 or 30 seconds, the piece is cooled too much. Dave