Hey guys,,,I have a bolt question,,so I thought I would ask the best in the land . I am coming along with my DeSoto,,,,and noticed that the oil pump mounting bolts are socket head cap screw . I have seen several pics of some engines having these bolts on the mains but I’m fairly certain the factory used hex bolts on the mains,,,,who really knows. Anyway,,,,,my engine had the crank reground to .020 under on the mains and throws . The bearings had a date of 1962,,,,,,,and the oil pump is attached with cap screws . I’m just wondering if this was the usual thing from the factory back then ? The bolts look really good,,,and have the letters P-K rolled into the heads,,,,and 3/8-16 on the back side . I have looked online for information about the manufacturer and quality,,,no luck yet . Here are some pics of what I’m seeing . Tommy
When the engine was rebuilt, people that were around high quality fasteners used socket head because they were better than grade 8. Bare in mind that to my knowledge, nobody made replacement bolt sets. If you had no access to new factory bolts, the socket head would have been an excellent replacement. I've never taken a DeSoto apart but the Chryslers and Dodges all had hex head.
Quick internet search says P-k could be Parker-Kalon which was or is a fastener. Manufacturer. I have a 276 Desoto that was original and I don’t recall it being a socket head cap screw. I’ll have to double check but I’m pretty sure it was a hex.
Thanks guys ! I’m not against using them,,,,they actually look like top quality parts,,,,I’ll probably put them back in . I’m with you guys,,,,all I have ever seen are hex head bolts,,,,,but I’ve only seen engines back to about 1962,,,,,Mopar wise . All were regular bolts . Tommy
Bert, I'm aware that most are. 150,000 psi tensile is standard for grade 8. Holo Krome is 170,000 and above depending on size.
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