So since completing this journey, I wanted to make a write up about my adventure. It’s slipped my mind for this long, but I thought about it and have a moment to do it, so I will. Take this as a fun, reckless, and impulsive story - or take it as some anecdotal evidence toward the durability of the OM617a. TL;DR: I am reckless, and the OM617a can (in a pinch) run on a dead cylinder. Let’s start with some context: Alex Vaughn and I have been planning for him to come up to PA to help me swap an OM617a from a 1983 300D in to a 1983 Dodge Ramcharger Prospector. The plan was for him to be up here for 5-6 days, and we get most of the heavy lifting done on the swap. Get the 617a refreshed, and get it mounted in the truck. I would address the rest in my own time. But I know he’s more knowledgeable with these engines and has a more “engineering” mind than I do so he’d be able to help figure out the mounting. Long story short, we hit some roadblocks and didn’t quite accomplish the goal. Now, while this plan is unfolding, I became aware of a 1978 300SD for sale in Ohio. I figured it was too far away, but Alex mentioned giving me a ride to Ohio on his way home to Kentucky. In that scenario, I would repair the issues with the 300SD that the P.O. diagnosed, and drive it home to PA. For those that don’t know me, I’ve been after a W116 300SD since learning there was an om617a in the W116 chassis. I absolutely love the w116 body, and the om617a is my favorite engine. So this is finally my chance, with minimal work! (or so I thought, from the P.O.’s diagnosis). To be clear, I am not throwing any shade on the P.O. here - he did everything to diagnose that I would have done. I would have come to the same conclusions he did. The vehicle needed front brakes and a single injector. Yeah, sure. I can fix that on-site and drive the car home. I wouldn’t have been nearly as confident of any of this if it weren’t for Alex, however. That man is quite intelligent and resourceful if any of you haven’t picked up on that yet. So, we finish the week of engine swapping and load up Ol Red (his ’78 non-turbo 300D) with all his tools, my tool box, and all the parts he could salvage off my donor w123 that he could take quickly and fit in his car. The original plan was for him to tow the donor car back to KY with him for parts, but he decided against it since it would severely delay our arrival in Ohio to pick up the w116. We loaded up on Friday evening (already low on sleep as we both only got ~4 hrs of sleep per night all that week), and around 9pm we set out for Ohio. This was a straight shot. We stopped driving for, at most, an hour here or there to take quick naps, and at one point he got way too tired to safely drive so we switched and I took over. I should note that Ol Red got some great mileage (27-28 MPG) considering how loaded it was with tools and parts, and wasn’t nearly as slow as I thought it would be. If I remember correctly, it was between 500-600 miles from Horsham, PA to Lima, OH. By the time we got to Lima, we had both been awake for over 24hrs with <2 hours of nap time scattered through there. This was getting sketchy already. We got to the seller’s house in Lima (from which he was moving THAT DAY, and needed the car gone THAT DAY), exhausted as hell. Worth noting that I had sent the seller a deposit on paypal, and given him my word. Due to my own constitution, I HAD to take the car. When I give my word, I keep it. I don’t have a whole lot to my name but I do have my word and it holds weight to me. Anyway - We pull up, and get out and talk to the seller about the journey and whatnot. I look over the w116 and I am over the moon. It’s a beautiful color in my opinion, anthracite grey, with minimal rust and the interior is not completely roached (which is what I was looking for in a w116 as I know the rust and the interior are really where you can get in to deep money). I am so happy that I will finally own an om617a powered w116. So, I unload my tools from Alex’s car, and we get to work. I work on the brakes as Alex works on the injector which was thought to be dead. As I am hurriedly working on the brakes (and making stupid mistakes) Alex discovers that the issue is not just an injector, but the prechamber in #3 is essentially missing - a failed injector or something has blown the insides completely out of the prechamber, and you can see the piston down through the hole where the bottom of the prechamber is supposed to be. And to add to that, as we crank the engine we find that one cylinder has no compression. It’s pretty easy to deduce that it’s cylinder 3, and the assumption is that the prechamber “crumbled” and chunks of it beat up the valves on their way out causing a lack of compression. Now I’m kind of panicking because I’m 600 miles from home and my only way to get home is a car with a 100% dead cylinder. We try to reach out to a few of the other knowledgeable guys in this community and ask for their input, but couldn’t reach any of them in the short amount of time that we had there. While this is going on, we find that the front passenger caliper is locked up as well. As luck would have it, the seller had a rebuild kit. Alex thankfully knew how to rebuild the caliper, so he did. I have never done one, so I had absolutely no idea what to do. Thankfully due to Alex’s resourcefulness we could get the caliper rebuilt and back on the car. With no other reasonable alternative, I decide to just go for it. Alex test drives the car around the seller’s neighborhood to see how it behaves. It’s quite sluggish as you’d expect, and smokes like a chimney from all the unburnt fuel. Other than that, it’s not TERRIBLE - no parts falling out the bottom, transmission shifts reasonably. So, we head out. We stick together until we get to a fuel station and both fill up. At that point we say our byes and head separate ways. I am completely on my own now, as he “cannot come back and save” me. Even if he could, I wouldn’t expect him to as I got myself in to this situation, and I would figure it out myself. I baby the car on to the interstate, and slowly bring it up to speed. The entire time I hold 50-65 as I don’t want to wring the engine out with a piston flopping around. I decide to stop every hundred miles to check my oil level and keep the tank topped up as I don’t know how much mileage has tanked from a dead cylinder. Throughout the journey, I seem to get 15-18mpg and my oil level doesn’t change. Shockingly this dead cylinder is not using noticeable amount of oil. Bear in mind, I still haven’t slept since I napped in Alex’s car. I make it through Ohio without incident, and in to western PA. Somewhere in the mountains around Pittsburgh, a heater hose (or the heater core itself) decide it wants to vent. I suddenly have steam billowing from my defrost vents, and a stink of coolant in the car. I quickly pull over, shut the car off, and begin to inspect. I pull down the knee panels on both sides of the car (as I am unfamiliar with this chassis, I just start ripping things apart to try to find a leak). I find no evidence of fluid inside the car. Bear in mind, this is around 3 in the morning on a mountain with no streetlights. My visibility is limited due to the only flashlight I have is my cell phone. I begin to panic, make a post in the w116 group asking for help, and reach out to Garrett. Being 3 hours behind my timezone, I figured he was my best chance of some knowledge that’s awake. While I’m waiting for any response, I open the hood and start inspecting the coolant hoses. I figure that since something vented under my dash, I should bypass the heater core to keep going. I traced the coolant lines, and after about 5 minutes figured out which lines I need to reroute to bypass it. I do so, and fill the coolant system up with water that I put in the trunk just in case something happened. I’m thanking god that I kept that water. With that issue temporarily addressed, I continue to drive. Somewhere along the journey, I get so tired I start to nod out behind the wheel. I immediately pull over, put my seat back, and take a nap. After about an hour, I keep going. Somewhere further east in to PA, the tired comes back again, along with body fatigue from the hours upon hours of driving. I pull in to a truck stop, get a cup of coffee, some ibuprofen for a pounding headache I have, and I rest in one of those massage chairs for ten minutes or so. That helps my back out, the coffee perks me up, and the ibuprofen starts to kick in. I get back on the road. After a few hours - driving across the elevation of the Eastern continental divide in foggy, damp cold - I start to get extremely cold. Like, losing feeling in my feet, shuddering cold. I pull in to another truck stop for some heavier clothes, and I get myself a drug rug to drape over my lap and keep my legs warm. I was wearing joggers and a crewneck, so my torso and arms were fine but the joggers did not keep my legs warm at all. I wrap myself up in the drug rug, and I keep driving. After a few more uneventful hours of driving, I get to where I am storing the car to this day, at my friend’s house in Fleetwood. Thankfully, Fleetwood was about an hour closer to my starting point than my actual house is. I get it there, call my girlfriend, and have her pick me up to take me home. Finally, I can rest. I sleep in the car, we get home, and I go directly to sleep. In the end, this adventure was one of the most reckless, impulsive, and irresponsible things I’ve done. I still have a 1978 300SD that needs an engine, a radiator, and something inside the dashboard. However, I have a 1978 300SD. The car will sit until I have the money and space to buy the donor car I have lined up for the engine swap, and the time to do said engine swap. It is definitely a weight on my shoulders, even though my friend assures me that I can take all the time I need and the car can stay on his property until I can repair it. I just continue to pressure myself about it and man, it really wears down on my psyche. I’ve even contemplated selling it a few times, just to get the weight off my shoulders. However, at the end of the day, I have the car I’ve been searching for, for a couple years now. My w126(s) were even “settling”. I wanted a w116 300sd, but couldn’t find one in my price range in reasonable condition. So I settled for my w126 (which, by the way, I love). However, I still kept looking for a w116 the entire time. And, for all you OM617a enthusiasts, this is evidence. I have not opened the engine AT ALL to see what damage has been done, but I know that on a stone dead cylinder, with raw fuel washing the rings out and who knows what kind of damage done by the FUBAR’d prechamber, that car made it damn near 600 miles at highway speed. The engine still starts up fairly quickly, and does not run any worse than it did when I began my journey (I still start it every week or so just for a few minutes or whenever I need to move it around the property). Moral of the story: I am reckless and irresponsible, and the OM617a is a damn sturdy engine that can take an absolute beating as long as it has oil in it.