Motor Mount Boss

[78Southwind]

Can this be fixed if the broken piece is missing? It's the motor mount boss /water pump hole, any ideas how to repair (weld)? It not a critical portion of the block but I would like to have it repaired while the engine is out of the boat.

[WESTERNAERO]

That needs attention! Your motor plate mounts there, I wouldn't want to run it with one bolt holding that corner of the engine.
If I were you I would give it the whole engine to that westernaero guy and go build yourself something new.
Seriously, I would have it welded, and then you can drill it thru all the way to the fuel pump rod stop hole. Then re-tap it thru and it should be fine. You'll need to run a longer bolt that almost enters the cross hole.

[78Southwind]

That needs attention! Your motor plate mounts there, I wouldn't want to run it with one bolt holding that corner of the engine.
If I were you I would give it the whole engine to that westernaero guy and go build yourself something new.
Seriously, I would have it welded, and then you can drill it thru all the way to the fuel pump rod stop hole. Then re-tap it thru and it should be fine. You'll need to run a longer bolt that almost enters the cross hole.

Can a welder build the entire area up with a big blob of weld, then drill and tap it? I am not sure if that will work with cast iron. The rear plates use 4 bolts for each side (which includes the water crossovers).

[WESTERNAERO]

Can a welder build the entire area up with a big blob of weld, then drill and tap it? I am not sure if that will work with cast iron. The rear plates use 4 bolts for each side (which includes the water crossovers).

If the plates go all the way to the water ports then you are in much better shape. I would still have it welded but i don't think it's all that necessary. No you really can't build it up with weld but you could make a small chunk and have that welded on. It was repaired before, you can see where it was drilled in areas to get the JBweld to stick better. I would still drill and tap all the way thru.

[78Southwind]

If the plates go all the way to the water ports then you are in much better shape. I would still have it welded but i don't think it's all that necessary. No you really can't build it up with weld but you could make a small chunk and have that welded on. It was repaired before, you can see where it was drilled in areas to get the JBweld to stick better. I would still drill and tap all the way thru.

Yep...they go all the way to the water ports.

[WESTERNAERO]

Are you handy with a jig saw or do you have a band saw? I would make a new motor plate that is one piece. Connected in the middle so those aren't trying to spread apart. May be the reason that boss is blown out to the side to begin with.

[obnoxious001]

Can this be fixed if the broken piece is missing? It's the motor mount boss /water pump hole, any ideas how to repair (weld)? It not a critical portion of the block but I would like to have it repaired while the engine is out of the boat.

I would almost just suggest replacing the block if you had some reason the engine was going to be out and apart. I don't think it can be properly welded without heating it up, and then properly bringing temperature back down after it's welded. You might want to find out what it costs too. One time I had a block repaired, and I made the guy promise it would not distort the cylinders out of round. I took it straight from being welded to the machine shop where they stuck it on the Sunnen hone, made a couple of passes with the stones and showed me that it had been pulled out of round. The welding shop didn't charge me, but I had to get another block machined and start over.

[WESTERNAERO]

I would almost just suggest replacing the block if you had some reason the engine was going to be out and apart. I don't think it can be properly welded without heating it up, and then properly bringing temperature back down after it's welded. You might want to find out what it costs too. One time I had a block repaired, and I made the guy promise it would not distort the cylinders out of round. I took it straight from being welded to the machine shop where they stuck it on the Sunnen hone, made a couple of passes with the stones and showed me that it had been pulled out of round. The welding shop didn't charge me, but I had to get another block machined and start over.

I believe he has a Dart block and I doubt he wants to spend that kind of money on a new block. The area where its broken can be fixed without over heating the block. Really it just needs to be drilled thru and tapped. If he has the piece that broke off it would be even better for a repair. But, if he makes a new motor plate I wouldn't even bother with the repair and it would need just the drill and tap.

[Menace Marine]

What is wrong with the current mount setup that put so much stress on the corner of the block?

[WESTERNAERO]

My opinion on how it broke to begin with is the the holes drilled in the motor plate were not quite in the right place. Probably drilled with a 7/16 drill and no clearance. When the bolt was run it it was putting a side load on the casting and popped that piece off. The aluminum is stronger than the cast iron right there so something had to give.