Are you sure it wasn’t aluminum?
No. They were stainless skinned. Often only partly painted. PD-4501 Scenicruiser - Wikipedia
I see on wiki they state they were repowered to 6v71 and 8v71 engines though I am pretty certain the one I looked at had been repowered to an 8v92. I have a couple inline 8-92 engines and the 92 series engines are less common than the 61 series.
What? Pictures please. Learning moment here. I never have seen an inline 8 cylinder two stroke Detroit. I always thought all the 92s were Vs.
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HI Bruce,
I oopsed and typed 8-92 They are 6-92’s. They came out of a pair of Freightliner semi’s that were donated to my dad’s vocational school when the owner retired from trucking. Yes - they are inline 92 series. Detroit made them also in 8 cylinder. The school’s agricultural mechanic’s shop had the welding department make stands for them but the students screwed up and didn’t make the stands so that the engines could be run in the stands. Made useless displays out of them. I bought them thinking they were 6-71’s. Oops. I’ve seen the inline 8’s in marine applications where a pair of inline engines fit better than V configuration. Sadly the 92 series is not considered as successful as the 71 series.
I’ll try to remember to get some pictures for you. They are likely going to scrap this year.
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Well, I went Google fuing as Cody calls it. I can’t find any 8 cylinder inline two strokes. The last straight eights I saw where gasoline engines from the forties…a Pontiac.
I did find the 51 series with no valves. 2-51, and 4-51s very cool.
An inline 6-92 would be really fun. Were the 110s offered in an inline six?
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Hi Bruce,
It was neat that the Detroit 2 strokes in-line 2,3, & 4 cylinder heads were also used to make the V 4,6,8’s. Then there were the couplers used to join a pair of engines. One of my truckers had a cab over short bunk Peterbuilt with a 12v71 that he hauled gravel trains with. Gawd that engine was big for a truck and a torque monster. The engines were a bugger to get perfectly adjusted so that their idle didn’t have a gallop to it. His lead trailer was 30cu/yd. The pup easily held 24 cu/yd. He’d bring it in fully loaded - illegally overweight of course. I’d watch him back into the bins and with the engine at idle the tandem drive wheels would slip with every romp of the engine’s gallop. Over time they played with adding turbos to it and larger injectors. I remember them saying that they took it to over 900hp. I’d swear they said over 1000hp at one point but then changed turbo’s.
They had me help change the transmission with my forklifts when they special ordered an over size unit that had to be lifted up between the frame rails on it’s side - then rolled upright and joined to the engine. They claimed it was the heaviest duty transmission available. - what ever that means.
They kept shearing the ring gear bolts in the drive axles. Wanted me to set the differentials up in a mill and drill the gears and differentials for larger diameter bolts. They wanted to use cap screws. I didn’t want to mess with drilling hard gears so they took it elsewhere and used cheap cap screws which broke. Dad told them to change to Holo-chrome brand cap screws. I think that was the last they did the diffs. They got rid of the truck shortly afterward. One of the sons - Burt - was a lousy driver. He loved using all the power the engine could put out. He kept breaking the truck with his rough shod approach and would often drop fuel mileage into the low 4mpg range.
You are correct - finding info on the in-line 92’s is crazy difficult. Heck - wiki claims they are bored out V-71 series engines which is not correct.
I am not familiar with the 110’s. There are a number of larger prime mover type engines that they made for generator and other industrial uses that I know nothing about.
I’ve got a Chrysler straight 8 in an Insley K-12 that needs a new home. Had more of them in the plant. One was for the Osgood 200 crane. The fire ruined them. So much stuff needs to find homes or be sent on a final one way trip.
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I was trying to find out if anyone anywhere still made a straight 8. None that I could find either. Apparently the late 1940’s Packards were the best.
I have a question. If you were to make a duel fuel diesel with a sparked ignition for wood gas would there be any issue with fouling the plugs if they sat unused for any amount of time. Now that I know it’s not difficult to do a sparked diesel I have gotten real curious about it.
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Tom,
If I read this correctly, you are asking if just the act of sitting would foul out the plugs? I believe it would depend on the last state the engine was in when it shut down. If you shut down with tarry gas, or acidic gas…I would expect the plugs to corrode. If you fog it, prolly not.
I have rolled well cared for gasoline engines that were parked 20 years prior. The Lorain is one example.
Diesel engines can sit even longer.
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I have zero experience with diesels other than turning a key Bruce. But that is the gist of the question. I can see that it would somewhat depend on the last source of fuel. I see diesels pouring out huge plumes of exhaust smoke and wondered if all that unburned fuel would wet down the spark plugs. I guess not an issue if you restarted on diesel before switching to WG. I guess that Tone’s tractor proving you can run WG with only a small amount of Diesel makes going to all the effort of converting to a spark plug less attractive. Unless it was a strictly WG converted engine.
Ok gottcha Tom. I would point to International Harvester. During the 40s and 50s they ran a style of engine in the WD-9, WD-6, TD-9, TD-6 wheeled tractors and tracked crawlers. They started on gasoline. They had a gasoline tank, carburetor, magneto, and spark plugs. Once they were warm, you pulled a lever that switched something in the engine, raising the compression. Then it was a diesel. It had an injector pump and injectors, and burned oil. One side of the engine was gasoline, and the other side was diesel.
I had one given to me, and given to me running because the guy was afraid to shut it off. It needed a starter and he pull started it. Anyhow, in my rush to be deployed to Iraq, I forgot to check the antifreeze. When I got back, the engine was cracked to pieces. It was an MD.
That engine’s spark plugs survived running in a diesel engine.
This video shows some of the details.
I bet you can see one at Buckley too.
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Goes to show, regardless of what you think, someone has already thought of it.
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I still have 3 of the IH series diesels at my shop. 2 are TD-9 bulldozers and one is a TD-6. Sadly - they will likely make the one way trip to the scrap yard this year. I already sold the IH/Farmall 450D farm tractor that I had which uses a similar engine.
Those diesels have a 3rd valve in each combustion chamber of the head that is manually opened with a starting lever. When opened - the valves opens a chamber that contains the spark plug. The added volume of the spark plug chamber lowers the compression allowing the weak - typically 6 volt starting motor - to crank the motor over for starting. The starting lever also activates the ignition. In the start setting - the engine draws air/fuel through a unique carburetor that has a fixed throttle setting. Just enough to allow the engine to start and run. Once warmed sufficiently - the starting lever is released - and the 3rd valve in each chamber closes - allowing the engine to have sufficient compression to run on diesel. At this setting the spark plug is not exposed to the diesel combustion process. The diesel fuel pump operates as normal and is set to the off position for starting. I would test for sufficient engine preheat by advancing the diesel throttle. If the engine would speed up - it was ready to run on diesel and the start lever was released. The engine would then run with throttle speed selected by the diesel throttle setting
The down side of these engines was that the combustion flame would pass the 3rd valve during the start process. The 3rd valves easily overheated and had short life.
I would think that you would be able to have a spark plug exposed to the diesel combustion process and not foul if one of sufficient heat range were used.
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The 2 stroke Detroit Diesel uses a unitized fuel injector. supply it with a constant source of fuel and everything needed to make the engine run is in the injector.
The engine camshaft(s) operate a spring loaded plunger in the injector that is the high pressure pump. Rotating the plunger regulates the amount of fuel that is pumped with each stroke of the plunger. The plunger is rotated via a rack and pinion type of gear. The pinion gear is fitted to the plunger. Moving the rack in and out of the injector rotates the gear and plunger - regulating the amount of fuel delivered. There are no seals for containing the high pressure fuel. Precision fit of the components separates the fuel from engine oil.
Runaway at starting can result from the engine sitting for an extended period. The governors are spring loaded and typically move the fuel racks to full fuel when shut down. All fuel racks are mechanically joined together. They function in unison.
While sitting, the fuel in the injector dries/varnishes. This can stick the plungers in the depressed position or they can stick down when the motor is rolled over. If this happens with every cylinder - the engine will not start. However - if one or more injector operates - the stuck injector(s) will not allow the fuel racks on any injector to be moved to low speed or off position. Thus - the engine runs uncontrollably at full throttle on the operating injectors.
It is possible to improperly adjust the fuel racks resulting in the governor not being able to move the fuel racks to the off position.
It is also possible to assemble the governor in a manner that prevents it from being able to function.
I had these experiences with an engine that was salvaged from a Vietnam era swamp buggy. The engine had sat for a decade - gluing the injectors. I had to change the governor to one from a truck. When I started the engine - it went to full throttle. I’d not hooked up the emergency kill flap. The air intake was not connected to the air cleaner. Heck - the radiator wasn’t even installed. I started the engine and the 6V53 went full speed - well past it’s 2950 rpm limit. I had no means of shutting it down. I sat one butt cheek on the 5" air intake to shut it down. It took a number of wash/wear cycles for the circle formed in my blue jeans to subside.
I made sure that NEVER happened again.
One interesting aspect of the 2 stroke Detroit diesel is that it can run in reverse rotation. I had to make sure that I taught drivers to pay attention to the engine sound if they stalled it in gear. The truck could roll backwards - starting the engine in reverse rotation. Of course the engine oil pump does not function when this occurs so the driver must shut the engine off immediately. The fact that the engine is running backwards is pretty obvious as now the supercharger is sucking air from the exhaust and through the engine and out the air cleaner. It sounds strange when this occurs.
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Caterpiller 3608 is a straight 8. but it isn’t sold in emissions regulated countries. You would have to sneak it in from an indian reservation. 
However, if you want something useful, this one should be able to run your water pumps and maybe your lights. It is a v12 but converted to woodgas, all would be dandy!
https://grandrapids.craigslist.org/hvo/d/wellston-cat-generator/7452353789.html
(sorry I have been trying to work that into a post for like week and a half. )
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I watch a lot of youtube on my TV. I keep on seeing a lot of video about these Detroit Diesel engines but can’t link them from the TV to here. Just saying, there’s a lot of information on them out there.
Here are some photos of what I had figured were 6-92 Detroits. The large round cover at the upper front of the engine precludes them from being 6-71 series.
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Model 1067-8000 comes up as a 671.
You have some real treasure there.
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Well…I’ve owned
(3) 6-71’s and these are different. Even the 3 and 4-71’s I have look like short versions of the 6-71’s. I still have one 6-71 in my Pettibone 5 yd loader. The rear gear housing is different. The front water pump and housing is different. Oil fill is different. If they are actually 6-71 blocks with totally different ends than I am familiar with - I’m gonna feel really stupid. Guess I can measure the length of the valve cover and compare with the one in my loader.
The treasure was the low time 6-71 with allison trans that went out for scrap last year. The valve bridges still had their ground finish where they contacted the valves. I shouldn’t have let a friend talk me into scrapping it. I should have pulled it apart to use it’s parts to rebuild the 4-71 in my Drott 40 feller/buncher now excavator with thumb.
Those three words can be a powerful lesson for the future. I am going to treat today accordingly and not look back at today and say it.
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