241 Hemi Long Block Rebuild Part One
I am building a 1929 Ford Roadster the way I imagine my Grandpa and his buddies would have built back in the mid-fifties. Trying to stay true to tradition I am using as many period correct parts as I can. This article chronicles the purchase, study, and rebuild of my ’54 241 Dodge Red Ram engine long block. Hopefully it can help you if you are considering an early Hemi for your hot rod! Being in my mid-thirties it is hard to believe it has already been 10 years since I first laid eyes on the engine I am writing about now. It was a cold Nebraska day in mid-March when I visited a farm just east of Lincoln to look at an old 1954 Coronet that was for sale. The car had sunk to its axles in the side of the field where it sat. Its interior was destroyed by the elements with windows down and driver’s door hanging half open. The poor two-tone green sedan looked sad on that windy day but a quick look under the hood told me it was worth the $500 asking price. I paid for it and continued to spend half a day releasing it from the clutches of the frozen tundra. I removed the engine and transmission with the help of a friend two days later. The 241 Red Ram was greasy, rusty, and stuck solid. One frost plug was corroded through, and another one looked like it was pushed out slightly. I worried about a cracked block, but never gave up hope it would come to life again someday.
It sat in the corner of my garage for many years. During that time I looked at the old engine, took pictures of my kids standing next to it, and grew to really like the way it looked with an old Edmunds intake sitting up top. 241 / 270 Dodges are small in comparison to their Chrysler 331, 354, and 392 counterparts. When assembled they actually do not weigh much more than a small block Chevy (590 pounds dry). Even with a stock water pump they are dimensionally small and swapping these into hot rods didn’t typically require the cutting of an old Ford firewall. All of these attributes made an early Dodge or Desoto Hemi popular with early hot rodders. You might ask about power? They are certainly not power houses by modern standards but had their day in the sun being introduced just before the production Chevy V8. An overhead valve arrangement with a hemispherical combustion chamber adopted from WW2 era engines gave early Hemis a serious leg up on most Ford Flatheads of the time. In stock trim for 1954 power was advertised as 150hp with 7.5:1 compression pistons. 1954 was Dodge’s 40th anniversary year, and as a company they were proud of their new V8. That year they took four Hemi powered 54’ Dodges to the Bonneville Salt Flats and set 196 new AAA-certified speed records. This included a 108.36 MPH tally for the flying 10-mile mark in a sedan. Dodge also had a great showing at the Carrera Panamericana road race taking the top four spots in the Medium Stock class. One of the 54 Dodges being wheeled by Tommy Drisdale averaged 90 MPH for the entire 1,908 mile event. One was even adapted for use at Indy!
Despite being small in displacement, it is safe to say this little Dodge engine was an engineering triumph for its time and more than good enough for my little hot rod! With a roadster hot rod taking shape in 2014 I started the process of tearing down my 241. With my kids sleeping in their rooms above the garage I quietly worked to get it apart which was complicated by stuck pistons. Prior to disassembly I soaked the cylinders in what the internet had determined to be best, (a concoction of ATF and Marvel Mystery Oil), but even after months of waiting and the crank would still not budge. This really made it tough to remove the torque converter from the crank as the bolts were inaccessible without spinning the engine. I made due, and slowly the all-important internals of the engine could evaluated.
When disassembling any engine it is so important to be organized! I used zip-lock bags and a sharpie marker to label everything. Even if I was sure it would not be used again I labeled it! Once the parts were bagged I put everything in a big box to refer back to later.
Typical of an old engine that had been neglected a thick cake of grease covered everything inside. The reason the old car was parked in '65 became apparent when I looked at the cam. The lobes were severely worn with some even completely flattened. It looked like oil changes weren't high on the last operator's priority list. Aside from a sad looking cam the other parts looked ok. There was a light coat of surface rust in the cylinders with exhaust valves open to the elements which caused those pistons to be stuck.
After removing the rod cap nuts, I used a wooden block and mallet to drive them them up enough to clear the crank journals. As soon as the crank could be removed I tapped them back through the bottom crank case.
Being fairly brittle if you ever have to do this be careful to use a wide wood block or tap on the area nearest the pin bosses to keep from shattering the piston. Also be careful for the bores as you don’t want any self-inflicted damage to the cylinder walls. If you have never disassembled an engine before, be careful to keep each rod cap with its original rod and keep the main caps and bolts with the block. Again carefully recording where all of the parts came from is very important! Here’s where we leave this one. There are a lot of moving parts and pieces to keep track of, so I have a lot of work to do. I’ve boxed up the major bits and pieces and loaded them into the truck, and it’s off to the machine shop with those!
Continue reading Part Two of Tim's 241 Hemi Long Block Rebuild.