New project: 1933 Dodge truck "Rat Rod" engine swap= 1980 OM616 - PeachParts Mercedes-Benz Forum

ROLLGUY · #1 04-17-2023, 03:38 PM

My friend is a total "Diesel Guy", so he asked me to do an engine swap on this Rat Rod he purchased a while back. It came with a Ford Y block V8 (1954-1964) and cast iron transmission (2 speed?). He bought a running 1980 240D manual trans for the swap. After pulling the old drivetrain, I set the 616/4spd in the chassis. It actually fits rather well, almost like it was made for it. Since the truck does not have power brakes, A/C, or power steering, I will be removing the PS pump bracket, A/C compressor and bracket, and even the vacuum pump. I will use a choke cable as an engine stop. I will be making a block off plate for the vac pump, and moving the fuel filter stand to the head (holes line up perfectly). I will need to lengthen the fuel hoses to and from the IP. The motor mounts will be challenging, as the arms stick out too far. I may have to totally fabricate mounts from scratch. More photos and play-by-play as the work progresses.

ROLLGUY · #2 04-17-2023, 03:41 PM

Photos of the 616 coming out of the 240D chassis, and in the truck.

By the way, I have the 1980 240D minus the engine, trans, and other related parts for sale. It is in Hesperia, CA. Light ivory/Palomino, no sunroof, crank windows. Decent body, needs rear windshield installed (comes with the car). I will post ad + photos in for sale section.

ROLLGUY · #3 04-17-2023, 09:26 PM

The motor mount arms were too long, and needed to be shortened. The motor mounts need to sit next to the frame, otherwise the engine will be too high. I cut off about 2 inches and drilled a 1" hole in each arm with a friend's milling machine. He machined a piece of 1" round aluminum with a hole for a through bolt for each one. He then welded everything together. I used his sand blaster to finish them. They look pretty good!

TimFreeh · #4 04-17-2023, 11:17 PM

Very nice work!

engatwork · #5 04-18-2023, 08:13 PM

Cool, looks good.

ROLLGUY · #6 04-18-2023, 08:39 PM

Thank you all for the kind words! I had a chance to work on the motor mounts today. I cut a six inch long piece of 4X2 rectangular tubing on two opposite corners to make an "L". I drilled the holes for the mounting bolts, as well as a larger hole in the middle that is big enough for a hex socket to fit. I bolted everything together and welded the top and bottom of the short leg of the "L" to the frame. I dusted the aluminum mount arms with a sloppy coat of flat black paint, so they would look "authentic". And no I am NOT going to paint any of the new metal I welded today! The engine is resting on the engine mounts, so now I can work on the transmission mount. I am planning to use the factory 240D crossmember, and just weld a bar on each side of the frame that will bolt to the crossmember.

ROLLGUY · #7 04-19-2023, 06:41 PM

Since the fuel lines need to be custom length, I found that 1/4" ID polyethylene tubing and single ear stepless clamps work great! I re-routed the glow plug harness so it goes to the rear of the engine, and will install a Ford solenoid and push button for glowing. For the dipstick bracket, it just so happens to bolt in one of the holes that held the PS pump bracket! I was looking for material to make a vac pump block plate from, and found this "No Skate Boarding" sign. I cut out and drilled the plate so some of the letters are showing. I think it is perfect for that "Rat Rod" look.

ROLLGUY · #8 04-19-2023, 06:43 PM

Also, I modified one of my oil cooler hose brackets to hold the hoses closer to the block.

t walgamuth · #9 04-22-2023, 08:33 AM

Michael had to shorten the arms on the 300 motor to fit the 39 Studebaker coupe express frame. He did something similar to what you did.

ROLLGUY · #10 04-22-2023, 09:09 AM

Quote:

Originally Posted by t walgamuth

Michael had to shorten the arms on the 300 motor to fit the 39 Studebaker coupe express frame. He did something similar to what you did.

I fount that to be easier than cutting and drilling plates to bolt on the block. "Great minds think alike"

BillGrissom · #11 04-26-2023, 03:32 PM

Nice work and looks like you have an AC-TIG for those nice aluminum welds. Perhaps the M-B rubber mounts last longer on the non-turbo 4-cyl engines, otherwise I'd be tempted to use flat mounts from another app like those on my 1960's Chrysler engines. I once bought Corvette mounts w/ hydraulic dampers and tried to fit to my 1985 M-B, but just a bit too tall to work. I was going to see if they made the engine smoother.

If you haven't fab'ed the vac pump cover yet, PM me if interested about an off-the-shelf part that might work. I bought one to try which "should fit" w/ correct bolt pattern, but haven't tried. That was towards an electric vacuum pump kit I was considering but may never get around to. If you mill from an aluminum plate, it will likely need to be thick to allow a recess to clear the roller-ramp on the timing sprocket, unless you remove that. Before I found the mentioned part, I had considered drilling holes in a stainless dish and even bought a few (large doggie dish). Long ago, people posted about running without a vac pump. Several thought there needs to be axial pressure on the timing sprocket to keep it aft, even rigging a spring w/ thrust bearing inside a gutted pump. Not sure necessary, but let us know what you think.

If your buddy ever decides he needs a brake booster, hobbyists are beginning to consider the 12 V motorized e-boosters which come in many current cars - Tesla, and hybrids like a CR-V my son rented (peered under hood), and perhaps even regular gas cars. If drum brakes, a manual MC is likely fine, but with front disks most people need boost.

ROLLGUY · #12 05-03-2023, 12:07 AM

I was able to devote a bunch of hours to this project the past couple days, and I got a lot done! I fabricated mounts to hold the rubber donuts for the radiator, fabricated mounts using the factory clips for the radiator, air cleaner, starter and alternator wiring, pedal box mounting plates (the firewall gets sandwiched between them), oil pressure and coolant temp sensors, and the driveshaft and center support (I still need to get the two ends of the rear shaft welded and balanced). Photos attached.

ROLLGUY · #13 05-03-2023, 12:10 AM

More photos:

I tapped the oil pressure line connection with a 1/4 pipe tap, and screwed in the adapter to the sensor.

ROLLGUY · #14 05-12-2023, 10:58 AM

I got the pedal assembly and master cylinder mounted, as well as the clutch master reservoir (motorcycle brake reservoir).

ROLLGUY · #15 05-13-2023, 08:32 PM

Just a few more details to finish, and the truck will be back on the road. I got the shifter mounted, shift rods shortened, oil cooler mounted, radiator hoses installed, vac pump cover fabricated and installed, and the glow plug solenoid mounted and wired.

I mounted the shifter flat on the floor close to the gap between both seats. I then bent all three shift rods straight, and then measured how much to remove (all three different now that the rods are straight). I cut and welded the rods, and installed them. It seems to shift just perfectly (I'll know better once it is driveable). I made a bracket the hold the oil cooler on top, and drilled a hole in the tab to mount it on the bottom. I had to mount the cooler upside-down, as the hose length would not allow it to mount the other way. I installed the radiator hoses (had to shorten them a bit), and installed the fabricated vac pump cover. I had a friend roll a ring out of aluminum, and I silicone'd the cover to the ring inside. I used a portion of a valve cover gasket to seal it against the block. I used the old Ford Starter solenoid for the glow plugs. I may just hook it up to the starter wire, so it glows only while cranking. If that does not work well, I will just add a push button.