So at school we have this pile of crap 2-71 Detroit that came off of a dredge. I changed the oil and fuel filters and pulled the valve cover and found a stuck injector. I had a set of 9290 injectors from an 8V92 i'm currently in the process of rebuilding. So I replaced both injectors with the 9290s, the ones in it were N45s. Flapper is open and it looks like it's getting fuel because you can hear the injectors squirt when the engine is cranked. It won't fire on any start aids either, which baffles me. Any thoughts from the mechanics 3 times my age?
Too much fuel, not enough compression? I'm assuming you've run the valve settings and timed the injectors with some sort of timing tool?
Yes I timed them with the timing tool and run the rack. I may have not timed them correctly.
Look at the blower rotors when cranking the engine to see if they are turning. Could be a broken blower drive shaft. Also, prime the fuel system at the secondary filter to make sure you are not getting air in the system.
You say you "hear" the injectors squirting, do you have lots of white smoke coming out the exhaust?
Small puffs.
When I was working on Detroits I had an Eagle (gold colored) oil can that I removed the spout and screwed in a fitting. I added a piece of braided hose about 2 feet long with #4 fittings. That way you can take a plug out of the secondary filter and hook up the hose and hand pump diesel through the fuel system to purge all the air if there is any.
Without being there it sounds like you are not getting good amount of fuel.
Knew a guy had a locomotive oil can with a pump, worked great, thing held like a half gallon of diesel....
Lots of them came with a fiber drive gear on the blower. Not uncommon for them to strip. A steel gear is available for replacement. A completely plugged air cleaner will give the symptons you discribed. I had a herd of kangaroo mice build a nest completely plugging the air cleaner intake pipe on a log skidder once driving me nuts until I found it.
Just needed a healthy shot of ether and some filters! https://vimeo.com/140860785
Great. Love the sound of them 2 stroke screamers. Its encouraging to hear that the school is still teaching some "old school" engine mechanics. Please post some pctures or better yet video when you can.
https://vimeo.com/140862393
Been watching this and cringing....my take is the school has failed this student. He had to come here, asking the internet on how to fix it. Graduated and fresh on the job, is the boss gonna like the new mechanic stopping to "ask the forum" for a simple task ? Not using critical thinking to work thru a problem engine ?
I'm trying to not jump to to many conclusions, but would have to wonder where the instructor was during this problem. If I was trying to teach someone the basics I would have been asking the student questions like what some of us did. Is it getting air? Is it getting fuel? And if the answers were yes next question might be, How do you know this?. I know I sometimes get sidetracked by over thinking a problem when the answer is to go back to the basics of what is needed for the system to do it's job be it an engine, hydraulic system, electrical item or what ever. Sometimes just stepping back and clearing the mind by doing something as simple as take time out to empty the trash will let you come back and start fresh at the basics. I do have to give CaptainAnalyzer credit for reaching out and asking questions, but would wonder where the instructor was during this problem. Also would caution against the temptation to reach for the "healthy shot of ether"! I also would caution against the attitude of referring to this unit as a "pile of crap 2-71 Detroit". It may not be all nice and shiny new but it can be a very valuable teaching tool! Plus I would be happy to have one that nice out in the garage to crank up when the power goes out after the Zombies attack!
"Suck, squish, bang, blow, if you got all four, she's sure to go."
Nobody gives a hoot about these old Detroits so it's up to someone like me to get donations and engines we dig up in bad condition to run.
Oh god please don't tell me you just said this.....
If it isn't a Tier 3 or better, automatic, or replaceable, why would anyone care nowdays. I'm part of a generation of throwaway, lightweight, plastic, aerodynamic, no character, and liability prone everything.
Everybody wants the easy way, no one wants to get dirty, the average diesel mechanic nowadays is 5'9" 140lbs. and knows more about plugging in scan tools than cutting, and welding.
So your very first job will be at the top ? Say you get sent out in your service truck to fix an older loader....gonna balk at it 'cause it has a sloppy, greasy, screamin detroit ? Refuse to work on it, and drive back to the shop ? The guy that's willing to get dirty, takes on "all commers" as a challenge, gets the work, and keeps his job when layoffs come around. Any monkey can work on the assembly line at cummins/cat/perkins....
I've been in the field the past two summers working on some pretty archaic equipment. 966B, v8 980's, D8Hs, 245s, 225s, 240Bs, -5 excavators, Koehring, Insley, Northwest, all that old stuff, old dirt pulverizers and rock crushers with engines from before my parents days like Cat D333, D342, D343, 353, 471, 671, 12v71 Detroits, 855 K19 and 903 Cummins. All that old garbage. I like to consider myself the exception to the rule because I firmly believe history should be known before you learn about DOC temps in and out, and urea dosing units.
Capt. Your attitude leaves a lot to be desired.
Archaic he says... old garbage.... hell in my world those are all in the prime of their lives, front line equipment. Must be nice to be that uptown, LOL
Is the OP being facetious and the sarcasm not getting through the screen? If not, I'm lost...
Captain: you need to work on your bedside manner a little bit with your geriatric patients and their loved ones. Here is an example to work towards https://www.youtube.com/watch?v=Nh-QOzHmr5s
don't knock those old demon's got one right now running life support for a screen plant after the deutz ran away.
went to the junk yard and got the accessory drive gear off of a 6v92 to run the pump. bet ya you won't do that in 20 years with these current engine designs hell you can't do it now
I like to consider myself the exception to the rule because I firmly believe history should be known before you learn about DOC temps in and out, and urea dosing units.[/QUOTE] Sounds to me like he was being sarcastic. If not i'll have to kidnap him and make him listen to about 4 of my Detroits running all at once. I for one am glad he took on the old screamer.
Lol. I'm on your guys side. Please chill everyone.
This made me smile. Thank you!
I've learned a company cannot be efficient with dated equipment in the N. Illinois construction industry. I have a fetish with old engines and equipment.
Don't know about Illinois, but I rebuilt an old 8V92 in a tipper for an old guy who owned it for years and used it as a contractor for road jobs. He was proud as punch with that old girl, all the other guys on the job had latest electronic trucks, and reckon his old Inter was the most reliable truck they had. Sure it was loud and sucked more fuel , but hey you can claim that on tax... and it just sounded soooo sweet!
There is something to be said about an engine that only needs electrical power to turn it over and that is only if it has one of the fancy newfangled electric cranks!
Have you ever heard of the Hydrostart option? Engines equipped with this had a hydraulic pump that would use pressure from an accumulator that you would charge with a hand pump similar to a bottle jack.
Yes all of the Detroits in Army/Navy boats I ever worked on had the hydraulic starter. No electrickery required...
Yes and you will have a bigger appreciation for electric starters after you run one of those out of fuel. Been there and done that.
Yes, I read the full Detroit Service Manual years ago. But don't forget about the air starters! We had several 16V-71's with those. They are even more popular in some areas these days as technology has improved greatly and the weight has come down way below that of the weight of an electric starter for the same engine!
Love air start, especially when starting up a truck or machine after an extended layup, or if it's just balky. Plug the hose from the service truck compressor in and off you go, no waiting for batteries to charge up, messing with booster cables, arcs, sparks, the danger of batteries exploding from the off-gassing of hydrogen.
We have a menagerie of air starters at Ferris State. Incredibly loud bastards.
CaptainAnalyzer, don't let those old geezers you give any guff on calling a Detroit was it is, an antique. I have a half dozen of them still in service and they make money for me, but in saying that, im as old as the engines in most cases. I keep em running as long as I can because I can work on them. But I also have the new models and they grieve me because I don't total understand all the things a computerized rig can tell you. Hel* some of us would still be running the old maytag one cylinders but that wouldn't be saying much for the evolution of mankind.
Grandpa, mankind hasn't evolved one damn bit. Sampson slew the philistines with the jawbone of an ass, them jawbones are still killing thousands a day only now they belong to asses called "President" and "Ayatollah" and "Shah" and suchlike and so forth.
In that respect lantraxco i'll have to agree with you.... and add it may even be regressing.
Have several of the Detroit's myself in trucks and equipment . Like grandpa said I keep them around because they are good earners . Very reliable and simple & cost effective to rebuild . Urea is something that should be loaded on the back of a fertilizer truck ......... Not part of the diesel engine system . I'm keeping the old Detroit & Cummins engines for the duration . Even enjoy working on them ....... LOL ! HeavyEquipmentForums
The company I work for has many old Detroits still in service and doing the job. I'd way sooner work on any of them than work on this new garbage they are calling diesel engines. Had an interesting experience recently that sort of ties into all of this. I needed to have 1974 vintage Cummins KTA2300 overhauled. That's fairly big girl. V12, twin turbo, 1000HP @ 1800 RPM. It's in a critical application so I called in the local Cummins dealer to do the work. Why take chances, right? Call in the pro's. Well, not only had no one working at the dealership every seen or even heard of a KTA2300 before......it turned out that Cummins headquarters in the change over from paper to computer hadn't bothered to keep any information on engine serial numbers built before 1978. Getting the right parts was a nightmare. The 1 week job quickly tuned into a month of pure entertainment. It turns out the first 100 or so engines of this series built had a very special cam configurations that used a unique firing order and required an unusual timing setup. Luckily, one of the techs was older & had the common (diesel) sense to figure out what was going on and how to work around it. This kinda thing is what we have to look forward to in the future.
The key to making $ for you. Some air start 2 stroke smoke. ["https://www.youtube.com/watch?v=wzMNnvPK8pQ"] It's 2 1150's in a V... Today they call it the QSK I've been getting the hint that Cummins wants to get rid of all the simple progress from 2000 on back. Hats off to the young crowd interested in this "old junk"
I recall when the KT1150's first came out. Actually our shop did the prototype installation of the first one in a Hough 560 Payloader! Cummins factory people came out to our quarry and took lots of measurements off the machine and components like the Torque converter. They then gave drawings to our welders to fabricate brackets and mounts. Once the installation was done and some minor modifications made the local Cummins dealer took over and did a few more conversions for our company. Kind of upset our guys as they felt we should have been the ones getting the work. The company has a Komatsu WA600 with the KTA1150 in it that has over 25,000 hours on it and up to 23,800 hours had not had a head off it. Then it broke a valve spring on #2 intake valve. Heads rebuilt with new springs and about 1/2 the intake valves. Iron PPM for the last couple samples is in the mid 20's to low 30's so there is some wear creeping up but for a 19 year old engine it's still not too bad.
Air start appears to be the preferred option for today's big engines, especially when one of these will spin an engine over faster and more reliably over time (we used to overhaul starters at engine overhaul - 20,000 hours) than 2 x 50MT electric starters that weigh twice as much....... and that's before you think about the other benefit of only needing 2 batteries versus 6 ...... http://www.tdi-airstarter.com/air-starters/t50-p
But then you need air compressor, lines, storage tanks, etc. that if not otherwise needed for the machine probably warrant the use of electric starters.
Not when the machine already has an air system on it for the brakes you don't ........
Thought I covered that.
Sorry, missed that. I've worked with some machines where the air system only worked the horn unless it had air start on it, in which case it was used for the air start as well and TBH I'd take air start over electric every time for reliability and ease of maintenance.
My only experience with an air starter was on an old freight tractor that a former employer of mine purchased to shuttle trailers. We did not use it often, and one of two things seem to always happen: Either the air had leaked out, or it did not contain enough reservoir to get the engine started, which in either case meant having to get another vehicle with air to "jump" with air, to start. I'm sure that in many situations they are a much less expensive, and less problematic than electric start, but in my experience it was a pain in the posterior!
The older vane-type air motor starters were a PITA, the newer turbine starters are much better. They weigh about 1/3 of an electric starter which is good if you ever have to remove one, and in my experience they were pretty reliable because literally the only thing that wore out on them was the Bendix gear. Having had plenty of experience with air starters over the years I agree with you that it puts a premium on having air systems that are pretty much leak-free, although if a machine is working 24/7 the air never really gets chance to leak out during the short time the engines are stopped, during change of shifts for example.
Unless it's a later model Cat large OHT with the treadle valve that leaks like a sieve Nige...
It's on the PM schedule to replace the cartridge inside the treadle valve every 1000 operating hours. It's a 5 minute job involving removing 3 screws IIRC, not much more effort than replacing an air filter. Any operator who chooses not to do that then whinges that they're losing air from a leaking treadle vavle gets no sympathy from me.
Fair enough, but when customers used to achieve 20,000+ hours from the old treadle valve, then we go to a new one and it gets less than 2000... Not fair to the customers to fork out the additional expense. We have trials going on around here with the old treadle valve and an in line air filter to clean up the air supply before it gets to the treadle.
Just as a side note for air starters I'll relate a little story: I worked with a welder that welded 300' boats here in Erie, Pa during WW2, and he said they were outfitted with "union diesels" that ran air starting, 600 psi and applied directly to the cylinders thru a valve linkage. They also ran both directions, in needing reverse, you would shut the engine down, change the valve timing/linkage, puff in some air, and you would be running in reverse. He also related, most of the time, reverse usage was slight, so just motoring (in reverse) on the air was all that was needed. Along came the screaming detroits (as a design change), and a shifting gearbox was needed.
Well a Detroit "will run" backwards but not very good or for too long, oil pump and blower turning the wrong way is not good! Actually wonder if the reversing gear box was a simpler design than the reversing the rotation of the engine? Bet the idea of reversing engine rotation was the brain child of someone who got their start designing steam engines!
I've seen those old setups where the engine would run either direction, usually direct drive through a reduction, no clutch, with a shaft brake to stop the wheel spinning if i recall correctly. Seemed pretty good to me, but then an "old" engineer told me about having an engine that was balky when hot.... guess that would make for exciting moments.
Most marine diesels of that era will run both ways. It was always the SOP for reversing a ship until azimuth drives came in. Even ship's steam turbines had a forward and reverse turbine built into the same housing and whether they went foreward or backward depended on which turbine you put the steam supply on. To watch all the steam valves being spun open/closed manually while a ship was manoeuvring in harbour was a sight to see...
Detroits run backwards alright.......sometimes you didn't realize it until the air filters caught on fire, it's all downhill from there. In air compressor applications you really had to watch, just a little kick back and away the Detroit would go. Good fun. I believe some 2-stroke snowmobiles start up in reverse rotation to provide reverse gear. The idea is not dead yet!
The one time I saw it happen was back in 1968, remember because I had just started at the quarry a couple weeks before. Well driver in an old stick shift Euclid was pulling up a steep short grade in too low a gear. Truck stalled and before he could push clutch in it rolled back enough to restart the engine. Fortunately there were guys right there that new what had happened. Yelled at him to kill the engine then restarted it and back to work.
I heard a story of an old R-model 6-wheeler with an E6 that was crawling a grade on a jobsite that stalled and started in reverse. Driver said all his forward gears were reverse, no oil pressure, the excavator operator jumped from the cab of the machine to shut it off. The company still has that truck.
I have seen them run backwards a couple times in trucks that the clutch got pushed in to late crawling out of the woods. The smokes pours out of the intake but it was always kinda white and because the exhaust valve timing was way off and opening on the compression portion of the stroke. Made the engine run slow and dirty. Shut off quickly and restart to straighten out. I need some explaination on how the ship engine Detroit's (Maybe they were not Detroits) could be reversed to run counter rotation without changing the cam. Maybe it was possible to change the cam timing enough to make it run good enough to back up?
Did some Google search and no simple answers but at least one explanation mentioned a cam shaft that had two different sets of lobes on it and it was moved axially by hydraulic pressure. Say when running in "forward the cam was shifted to the front. When running in "reverse/astern" the cam would be shifted towards the rear of motor. This would address the valve and injector timing aspect. I can imagine the oil pump being designed with a set of check valves that would allow the flow to be automatically corrected for the selected rotation. Found another page that might explain it better: http://www.marinediesels.info/2_stroke_engine_parts/Other_info/lost_motion.htm
40 years ago a WWII Navy Vet told me about a big Fairbanks-Morse that he was around. Compassed air shifted the double lobe cams to run the engine right or left. His comment was that unless there was all kinds of room, it was best to have a yard tug close by for mooring help.
Here's an explanation of how it works on various makes of 4-stroke engine. http://www.brighthubengineering.com/marine-engines-machinery/60584-reversing-of-marine-engines/
FM's, were those twin crank, opposed piston lovelies? Always wanted to get up close and personal with one, never have.
Thank you for that Nige. Sliding the cam is most interesting. It would be fun to see one work to see how the pushrods move from the forward lobe to the reverse lobe. Its amazing the amount of engineering that shows up in different applications.
I actually had this happen on a 3406 B for just a second until I shut it of, same scenario - pulling out of a steep dock at an idle, stabbed the clutch at what must have been the perfect moment. Sounded funny with the exhaust coming out of the air filters.
The talk earlier about air start GM's reminded me of a time when the mine I was working at was looking at replacing the Cummins 1710's in the Euclid R 85's they ran as a way of getting a bit more speed / grunt out of them. They shoehorned a V 12 GM ( I think I am remembering silver series 92 but I could be wrong ) into that thing. They engineered mounts , pipes , brackets etc and bolted it up to the Allison tranny. It looked like it was meant to be in there. Time to fire it up. That air starter howled for two days before they realised the jimmy had decompression shafts. It did get up and boogie though when they got it on the haul road.
By the way , I have seen two Jap truck engines (both Hino now that I think about it ) run backwards for a few seconds . Both heavily loaded / stalled and run back down steep inclines. White smoke comes from just about everywhere it seems but I guess it's mostly intake system . Both switched off with the key and started straight up with no obvious ill effects.
I somehow managed to get 1 engine on a 2 engine Hitachi excavator to run backwards long enough to the destroy the air filter. Inline 6 cyl. diesel, Isuzu I think. 4 strokes can do it too I guess
Post #62 reminded me of many years ago when I was working in a mine in NV. They had an old 315 CFM compressor that had a 3-71 for an engine and in really cold weather, you'd pop an ether capsule in, discharge it and hit the starter. The cantankerous critter would fire and go to rocking back and forth. What was happening was that it would fire on one cylinder, then kick back and fire again, kick back and fire again. Instead of making a full revolution, it was only making 1/3 of a revolution back and forth. Cure? Shut it down, repeat start sequence and watch to make sure it ran properly. Sometimes in below zero conditions, you'd have to go through the start sequence several times.
Hey CaptianAnalizer. Don't let these old timers give you any flack, There will be a day when you are lamenting the good old days of urea injectors, catalyst, 35000 psi injection pressure, exaust filters, IR codes and pistons that go up and down! Instead of ion plasma hydrogen compressers that are always leaking the nucleus out of the center atoms of the magnetron and the operator still cant get a bucket full of dirt out of the ground. wes, class of 79, GO BULLDOGS!
Grandkobelco, Who you calling an oldtimer? The real oldtimers were like my dad. Here's a old picture of him running the pit loader when I was but a wee one! If you think the emissions were a problem with the old two-smoke Detroits, think about running one of these on a hot day in July!
Thank you very much Grandkobelco for your support. Are you still in the area? Where did you go after graduating?