Questions multiplying like rabbits

[drone_pilot]

I started to mount my alternator (B&C) on the 390 Thunderbolt engine that I purchased from Vans back during the Covid fiasco. The engine had been sitting in the corner of my hangar for a couple of years until recently hung on the motor mount. I mounted the alternator pivot bracket and then realized that I can’t find the holes for the alternator adjustment bracket. I then started looking at the data plate and noticed the engine shows YIO-390-EXP248. I’m pretty darn sure I had purchased an EXP119 originally. Does anyone know what the 248 designation is? I am going with SDS so I did have a lot of omissions on the engine (flywheel, fuel pump, fuel servo, spider, etc) when I made the purchase. Would this have turned the exp119 into a 248?

If anyone can help me figure out the alternator mounting, I’d appreciate it. Here are some pics of what I have so far. Note that there are no holes behind the gold anodized SDS Hall effect sensor bracket. Sorry. I didn’t get a pic of the top alternator bracket that I have but it’s basically the bar that bolts to the engine at one end and the other end is slotted for the alternator belt tension (pretty common). I hope that makes sense.

 

[Desert Rat]

On the exp-119 it's on that raised area behind the gold bracket in your picture

 

[drone_pilot]

On the exp-119 it's on that raised area behind the gold bracket in your picture

On mine, there is a raised round area behind the SDS Hall effect sensor that has not been drilled or tapped.

 

[Desert Rat]

I'd call Lycoming and ask them what the heck. If they missed machining that hole then they should cover it under warranty

 

[RBR]

Ben,
My designation is YIO-390-EXP240.
I retained your deletions: flywheel, fuel pump, fuel servo & spider. Like you I'm going SDS, but spark only. I therefore deleted the magnetos, but retained the accessory pad.
I would imagine that any change to the Van's standard -EXP119 would alter the final designation.

 

[drone_pilot]

I'd call Lycoming and ask them what the heck. If they missed machining that hole then they should cover it under warranty

Well, I was hoping that I was just overlooking something. That would've been easy, but then again we are talking airplanes, so I should know better. Looks like I need to make a call to Lycoming. It does look like an un-drilled pad is there under the SDS sensor. Going with SDS, the last thing I would've omitted from my engine is the main alternator!

 

[drone_pilot]

Ben,
My designation is YIO-390-EXP240.
I retained your deletions: flywheel, fuel pump, fuel servo & spider. Like you I'm going SDS, but spark only. I therefore deleted the magnetos, but retained the accessory pad.
I would imagine that any change to the Van's standard -EXP119 would alter the final designation.

That makes me feel better about the number on my engine. I retained the accessory pad also. I was hoping I wasn't shipped the wrong engine and didn't catch that until now.