Main Bearing Cap Screws

[Jocko_51_B3B]

Unfortunately I found coolant in the bottom of the oil pan and traced it to a cracked block. To make a long story short I found a good replacement block but upon disassembling it I discovered that all eight main bearing cap screws had split washers under the screw heads. Should they be there? Won't split washers affect the torque readings? I'm wondering if the washers were added by a previous owner. (The pistons are .030 oversize so work has been done on this engine before.)

 

 

Edited January 13, 2021 by Jocko_51_B3B

[billrigsby]

 

While I'm not sure about how lock washers or split washers would affect torque ratings or values, yes they do belong there, this is from the parts manual, and I also just went to check the block and associated parts that I got back from the Machine Shop which was stock and it does have lock washers.;

 

Here's some basic Fastener information;

10 tricks engineers need to know about fasteners

Edited January 14, 2021 by billrigsby

[Jocko_51_B3B]

Bill,

Thanks for the link to 10 tricks engineers need to know about fasteners. I will use the split washers just because Dodge put them there, but the article certainly calls their effectiveness into question. Not to start a side discussion about split washers, but if the theoretical purpose of split washers is to dig into both the bolt head and the work piece thus preventing loosening, then placing a flat plain washer under a split washer (which I see being done sometimes) to prevent digging into the work piece would seem to make the split washer even more ineffective.

Edited January 14, 2021 by Jocko_51_B3B

[JBNeal]

split lock washers also increase frictional force at thread engagement, helping to resist any fastener movement even through vibrations