Today's junkyard find
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Jarvis salvage yard ,in bellvernon ,got some odd some I'm sure theres more do to there being lot of odd buses and big rigs
Cool decoration for your garage or mancave.
Has anyone ever successfully converted a V series detroit supercharger to work on a gas engine? I see them all the time on eBay or craigslist for bargain prices since they aren't really useful for anything beyond their original purpose. Regular 671 blowers even in stock diesel trim without the extra drive pins and snout for belt drive on a gas engine, go for hundreds usually.
On an 871 blower, were they originally made by modifying a 671 case to take 8v71 rotors, or are they entirely an aftermarket creation like 1271 and 1471 blowers?
Has anyone ever successfully converted a V series detroit supercharger to work on a gas engine? I see them all the time on eBay or craigslist for bargain prices since they aren't really useful for anything beyond their original purpose. Regular 671 blowers even in stock diesel trim without the extra drive pins and snout for belt drive on a gas engine, go for hundreds usually.
On an 871 blower, were they originally made by modifying a 671 case to take 8v71 rotors, or are they entirely an aftermarket creation like 1271 and 1471 blowers?
Yes there's alot of info to convert it if I wanted to ,got to think people were doing this in the 60s and they couldn't call Summit up or jegs to get parts .I've seen V blowers on somethings in person and far as I can tell it involves new sealed bearings, correct end plates and apparently double pins aren't needed for just a cruiser but are for a race motor idk that's what I can gather but for 50$ it can sit and look pretty lol
Nope. The 8-71 is an as comes from the factory item.
The entire series is 3-53, 4-71, 6-71, 8-71 and, if memory serves, 12-71
It breaks down to 71 cubes per cylinder times the number of cylinders being furnished with air.
Remember that all these motors were 2-Strokes! Yessir, the Detroit Diesel line, which used the Jimmy blowers, was completely Two-Stroke. No spark plugs; the hottest spark in the world couldn't overcome the density of the air being stuffed into the cylinders by the charger and get the incoming mixture to fire. For a motor that was cold and needed to be warmed up they had glow plugs, kind of a hot element that protruded into the combustion chamber. It would get energized to assist with the combustion of the compressed air until the motor reached a temperature at which heat of compression would get the air sufficiently hot enough that it could ignite on its own The overlarge volume of air plus the high compression of the motor that caused that air to become extremely hot as it was compressed by the upstroke of the piston meant that just a small amount of diesel fuel had to be introduced into the combustion chamber at the appropriate moment and "WE have Ignition." The injection systems that fed the diesel oil into the cylinders were mechanical; rods and bellcranks.
As for application, the smaller versions appeared in industrial applications, the 6 and 8 were heavy truck motors and the 12 was a super heavy that got used in construction equipment.
Why 2-Strokes? Torque and time. They could provide huge amounts of torque and do it quickly because they had fewer working steps to go through to complete a cycle. Simply put, a 4-cycle motor has to go through four distinct movements, intake, compression, combustion, and exhaust to complete one entire cycle.
For the 2-Cycle, all this has been collapsed into 2 movements, compression/combustion, and exhaust/intake. This means that a complete cycle can occur in half the time of the 4-stroke which makes the 2-stroke more efficient. Exhaust gases exit by a valve but the incoming air enters through a port that is directly attached to and fed by the blower. The limiting factor to the 2-stroke was rpm; on the tachometer they hit the rev limiter very quickly and needed multiple gear sets in multiple transmissions to translate their basic output into useable forward movement.
My exposure to these engines came as a result of being a trades helper at a manufacturing facility that specialized in tree harvesters. For the motive for these machine they ran 6-71's mated to transmissions fitted with power take offs. The take offs drove the hydraulic pumps that ran the loading clam, the tip tray, the in-run feed rollers, the saw, and the off loading clam. At full production, those machines basically ran 24-7 unless they were pulled for service. In the bush, being self-propelled, they could and did move around to position themselves closer to the cutting being done. Alternatively, you could use a TimberJack or similar unit to bundle and drag the logs back to the harvester for processing. They became more or less obsolete when Koehring-Watrous introduced their single man units that could cut, strip, and load the log onto a trailer all in one process. The TimberJack machines, were, come to think of it, detroit diesel two-strokes as well. Still see the odd one around. They work great on a farm or wood lot and usually can be had for a reasonable price; just be prepared to do some work to get you old fossil running because finding one is only half the battle. They don't get sold if there is any breath of life still present in them so what you just bought is a project.
Nick
The entire series is 3-53, 4-71, 6-71, 8-71 and, if memory serves, 12-71
It breaks down to 71 cubes per cylinder times the number of cylinders being furnished with air.
Remember that all these motors were 2-Strokes! Yessir, the Detroit Diesel line, which used the Jimmy blowers, was completely Two-Stroke. No spark plugs; the hottest spark in the world couldn't overcome the density of the air being stuffed into the cylinders by the charger and get the incoming mixture to fire. For a motor that was cold and needed to be warmed up they had glow plugs, kind of a hot element that protruded into the combustion chamber. It would get energized to assist with the combustion of the compressed air until the motor reached a temperature at which heat of compression would get the air sufficiently hot enough that it could ignite on its own The overlarge volume of air plus the high compression of the motor that caused that air to become extremely hot as it was compressed by the upstroke of the piston meant that just a small amount of diesel fuel had to be introduced into the combustion chamber at the appropriate moment and "WE have Ignition." The injection systems that fed the diesel oil into the cylinders were mechanical; rods and bellcranks.
As for application, the smaller versions appeared in industrial applications, the 6 and 8 were heavy truck motors and the 12 was a super heavy that got used in construction equipment.
Why 2-Strokes? Torque and time. They could provide huge amounts of torque and do it quickly because they had fewer working steps to go through to complete a cycle. Simply put, a 4-cycle motor has to go through four distinct movements, intake, compression, combustion, and exhaust to complete one entire cycle.
For the 2-Cycle, all this has been collapsed into 2 movements, compression/combustion, and exhaust/intake. This means that a complete cycle can occur in half the time of the 4-stroke which makes the 2-stroke more efficient. Exhaust gases exit by a valve but the incoming air enters through a port that is directly attached to and fed by the blower. The limiting factor to the 2-stroke was rpm; on the tachometer they hit the rev limiter very quickly and needed multiple gear sets in multiple transmissions to translate their basic output into useable forward movement.
My exposure to these engines came as a result of being a trades helper at a manufacturing facility that specialized in tree harvesters. For the motive for these machine they ran 6-71's mated to transmissions fitted with power take offs. The take offs drove the hydraulic pumps that ran the loading clam, the tip tray, the in-run feed rollers, the saw, and the off loading clam. At full production, those machines basically ran 24-7 unless they were pulled for service. In the bush, being self-propelled, they could and did move around to position themselves closer to the cutting being done. Alternatively, you could use a TimberJack or similar unit to bundle and drag the logs back to the harvester for processing. They became more or less obsolete when Koehring-Watrous introduced their single man units that could cut, strip, and load the log onto a trailer all in one process. The TimberJack machines, were, come to think of it, detroit diesel two-strokes as well. Still see the odd one around. They work great on a farm or wood lot and usually can be had for a reasonable price; just be prepared to do some work to get you old fossil running because finding one is only half the battle. They don't get sold if there is any breath of life still present in them so what you just bought is a project.
Nick
The 12v71 could be had in semi trucks they were nicknamed "the buzzin' dozen" or "rocky mountain humming bird" for their distinct sound particularly when pulling a heavy loads up long hills. There was also 16v71 I'm pretty sure, although as I recall it was too large to put in anything like a truck and instead are mostly big industrial generator engines, etc. Anyway, they made the 12 and 16 using a bespoke block and crankshaft, but they use 671 and 8v71 cylinder (4 heads on one block for the 16v) heads, and two separate 6v or 8v superchargers. There is no such thing as a detroit 871 engine, or supercharger, only the 8v71 engines. The bolt pattern for the V engine superchargers is totally different where it mounts. Which is why I wondered if the larger 8v71 rotors can be stuffed into the smaller 671 blower case to make an 871 blower using all factory GM diesel parts, unlike an aftermarket 871 blower which is entirely an aftermarket performance creation as they never made an 871 engine.
Also I'm like 95% sure old two stroke detroit diesels don't have glow plugs. The 6.2 and 6.5 v8 four stroke diesels in older GM pickup trucks do though.
There was also a 92 series, the 8v92 is a pretty common marine engine, and used to be quite common as like greyhound bus engines. There's also 149 two stroke diesels, along with the 53 and 71. The 53 series came in a 6v configuration in some light armored military vehicles but is most common as a like 3 or 4 cylinder industrial or tractor engine.
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