1931 Chrysler CD8 Roadster Engine ready to start after 50 years

[Gunsmoke]

I've been spending time for 3 months preparing this engine (240CI from CD8 Sedan) for a trial start and run before removing entire drivetrain from the barnfind chassis. As far as I have been able to learn, engine was last run in the 60's when the car was brought to Virginia from NY. Plan is to use it in my Roadster project. I've completed most everything except for any rebuilding of major internals, i.e. crank/cam/pistons/rings/cylinder walls, all of which seemed fine. A compression test once running will tell the story on those items, fingers crossed. Have rebuilt or refurbished Head, full Valve Train, Starter, Generator, Oil Pump, Fuel Pump, Water Pump and fan belt, Radiator (and added temporary red hoses), Crankcase vent, Wiring Loom, Oil Pan and Filter, and accelerator/throttle linkage (mounting bracket was broken in 2 pieces as is normal for these). All new gaskets, wires, plugs, cap, points and condenser and refurbished distributor and set timing. After freeing up manifold butterfly, installed modern Carburetor recommended by CarbKing, it being a NOS Carter FY for a 1969 Ford inline 6 300CI engine. Fitted it to manifold riser and throttle lever is in perfect alignment with original throttle linkage rod. I had to make a corresponding lever to clamp to rod as shown, using a throttle lever from an older spare CLUM switch assembly. Have not decided on "choke solution" yet, may leave as is or remove modern choke and make a manual cable driven one. Made 1" special riser for fitting on top of carb to take clamp-on original air cleaner. Have a temp gas can set up and am installing temp dash today to receive OIL/AMP/TEMP gauges and ignition switch/coil (had to have pair of keys made for switch). Final steps will be to install miscellaneous wiring (amp/ign/coil/dist etc), and a temp exhaust, muffler, and battery. Also still have to replace frost plugs and add fluids. Looking forward to a smooth start!

Edited October 31, 2018 by Gunsmoke (see edit history)

[Spinneyhill]

Thanks for the photos. I am surprised at how similar that engine is to the Dodge Brothers 8 engine.

 

Remember the two core plugs at the back, under the starter crank. I recently found mine mostly blocked up behind and it took a bit of chiselling to clear it.

[Gunsmoke]

I understand the early 240CI CD8 block (has 3" dia pistons) is same block used in '31 Dodge DG8. Later Chrysler CD8 engines went to 3&1/8", and then 3.25" pistons. The 1930 Dodge DC8 used similar block bored to 2&7/8".

Edited November 1, 2018 by Gunsmoke (see edit history)

[keiser31]

Hoping for the best on your starting of the beast!

[Spinneyhill]

1 hour ago, Gunsmoke said:

I understand the early 240CI CD8 block (has 3" dia pistons) is same block used in '32 Dodge DG8. Later Chrysler CD8 engines went to 3&1/8", and then 3.25" pistons. 

Yes, I think so. There was extra stiffening needed to go bigger because it became a bit flexible with bigger bore.

 

That contraption in the head water outlet to operate the radiator shutters is not on the Dodge though!

 

Good luck with the startup. My DC is very easy to start once fuel reaches the carb. (which is an aftermarket Tillotson from the '30s and not that good according to CarbKing Jon).

[keiser31]

8 minutes ago, Spinneyhill said:

 

 

That contraption in the head water outlet to operate the radiator shutters is not on the Dodge though!

 

 

The DG8 did come with that "contraption".

Edited November 1, 2018 by keiser31 (see edit history)

[Gunsmoke]

It is interesting that the "fancier cars" often came with gizmos of dubious value even back then (I don't want to even start a list of the dubious features on today's cars). I doubt the manifold "butterfly" worked for very long, regardless of it's potential value, as soon as any amount of carbon build-up got on the valve it will not close properly. The thermostatically controlled shutters required the owner to oil the top and bottom pivots every few thousand miles, almost impossible locations to get to and cannot be seen without taking rad out of car! I doubt they served any real purpose, perhaps avoided a "winter shield". Most probably seized in the open position within a few years. I took the thermostat apart and cleaned it up and have all the louvers freed up, oiled and working now, so it may work for a while. Springs in the hidden assembly pull it closed when engine cools. It will be easy if necessary to open it permanently by adjusting the turnbuckle and clamping the pivot lever in a fixed position.

 

I have 3 1931 MOPAR engines, a DG8, an early CD8 shown here and a late Deluxe CD8, and some parts from a 1930 DC8, all of which have several differences, too many to mention. While many parts are interchangeable, (heads, oil pumps for example) challenges exist. For example, the Chrysler heads have CD stamped on them. The DC8 manifolds have different thickness of flanges (about 9/16") where the intake and exhaust manifolds share a bolt, compared to 1/2" for CD8's, so you need to use a matching pair or make a custom varied thickness washer. Interestingly, the Chrysler intake manifold has no name on top, just firing order while DC8 intake has a large and proud "Dodge Brothers Corporation" cast into it. 

[Spinneyhill]

The trouble with oiling those top and bottom pivots on the shutters is that oil is a wetting agent and it won't take long for them to become a blob of oily dust. Grease would be a better lubricant; it doesn't wet dust anywhere as fast so will stay "clean" for much longer than an oiled joint.

[Gunsmoke]

Good thought on the pivots, when I do a final assembly of these parts I will look for a good grease.

[Spinneyhill]

Just a synthetic "chassis" grease would be fine, although for a very rare greasing you would be better without molybdenum disulphide (it is corrosive when the grease dries out). Hopefully synthetic grease stays "moist" for a long time and the volatiles don't dry out like they do in mineral grease.