Re: The new Burtz Mosel A engine
Got the crank and pistons in tonight, what an ordeal, The Clevite CB-745P STD bearings DO NOT sit flush with the surface of the saddle or caps. There's an interference fit when trying to set the bearing caps on the crank. I absolutely could not rotate the crank by hand the first time I installed only bearing caps 1 and 5 just hand tight. I realized right away there was an issue and got on the phone. I was able to get some official numbers to check and ask some questions. After getting off the phone, I checked the journal DIA and bore, both were within spec, must be the bearings.
With oversized bearings being suspect (circumference not thickness), I used my table saw as a flat surface and 400 grit sandpaper to "file" the ends down of each bearing, reducing their half circumferences. I also used a file to take off corners that may be interfering with the studs (yes I was using the correct studs) on bearing caps 1 and 3. 6 hours later, the crank could be rotated by hand with all caps torqued down to 55 ft-lbs. It's not silky but it'll do considering the crank can be rotated with a moderate force using a few fingers.
It's important to note that 2 of the caps didn't have a large enough reliefs cut for the notches in the bearings, requiring the bearing notch to be filed down slightly. This wasn't a big ordeal and was easy to spot/correct.
On to pistons/con rods. They went in beautifully. Going from hand tight to torque, I did notice additional resistance but it wasn't bad.
Full disclosure.....I am not an engine guy by any means. This is 1 of 3 engines I've ever built/rebuilt. I'm used to things just going together so this was indeed a bit frustrating but given the specialty of the motor, I'm not upset about running into issues. I will say, the manual could be a bit better with more concise step by step instructions and images. I'm absolutely looking forward to getting this thing running and can't wait to finish the car.
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