How to Set Maximum No Load RPM on Detroit Diesel 71 series 8v71 6v71
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- čas přidán 3. 07. 2024
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With that said, this video shows how I set the idle and max no load RPM on a Detroit Diesel 8v71 and 6v71 GM Coach - Auta a dopravní prostředky
Detroit 12v, 8v 71 series on PCFs and PB mk 3-4 , alpine green was their color name, doing weekly fuel dilution tests on them, runaway diesel- shut the air flaps, supercharged and turbos, setting the rack on fuel injectors, we even had a boat with 8v with advanced timing and n120 injectors, after a rather long run the engine broke - first time seeing a dropped valve "welded" on piston, -hooyah
I know of a company that were testing the 6-71 for the purpose of several single engine tug boats to use at their offshore platform construction yard. Referred to as "Yard Mules". Built a small cinder block house around it, mounted a water pump to use as a water dyno and completed their testing. Because the 40-60 psi fuel lines are near the Air Silencer and it's happened that when they leak the fuel is drawn into the Silencer and the engine runs away.
As a matter of destructive testing they bypassed the gov by pulling the Buffer screw and pushed directly on the Fuel rod of the Rack. At 6500rpm the Flywheel disintegrated the Bell Housing. How fast is the combustion process on an engine that can reach 3 times the rated rpm? The flywheel was probably the Allison MH Reduction gearbox common to the time. Guessing about 160lbs. With a better flywheel how much more rpm could've been attained?
I worked with the mechanic that was directly involved with the setup and implementation of this project in the late 70's.
Update: Using an optical tach I found my vintage SW in cab tachometer was reading slow by about 400 rpm. I found an adjustment screw on the back and set my 8v71 to 2350 no load and calibrated the tach to match. Truck runs great and I shift when it hits the governor. 8V71 governor does not seem to be working..or it's out of adjustment. I've hit 2700rpm upshifting (5 speed manual) and afraid to go higher by accident...can I just go counterclockwise a 1/4 turn at a time until it holds at 2450rpm without taking anything apart? (fire engine)
...and I am not responsible.....😁 Love that bit.
Any idea how to convert a 6v71 dual weight limited speed governor to a variable speed governor
sif pls tell me about rqv governor setting and reapair adjustment
Can you show how to set the gap on this type of governor, please.
I have detroit 6-71 engine in my truck and there is eaton 13 speed transmission .
My truck rpm goes full but truck speed very low
Whats the proble.?
Muy interesante su video,
Also works on a v53
You should run the spec rated RPM
Too low causes unburnt fuel to leak past exhaust gaskets
Unburnt fuel bc the blower at low rpm creates less air
2 cycle love to run high rpm,there designed to run in power band
Recommended max no load speed for a 71 series was 2250. Sometimes I would set them at 2300 when I was working at a GMC dealership.
I think they're made to run where GM says for the best for the engine. Never had a problem running the dog doodles out of one but it was within the specified r.p.m. range. Side open is one thing but overspeed is another. Never had any need for overspeed really.
GM's love to work, they don't like being revved hard with no load.
There should be a sheet of paper for your settings, no secrets 🐎🐂🇺🇸🙌🏁☕
What can you do to get all that is possible from one of these mounting it on a 460 for v8?
Can we consider that the power is reduced if we remove the turbo's on the 8V71TI engine ? Thanks for your input
Abdel
If it was a factory build TI engine it will run without the turbos but it will be flat in performance, factory turbo engines had lower compression ratio, so a Ti engine without turbo will have less power than a NA engine, it will also smoke a lot more.
What's the "buffer" gadget for?
Any idea where the tachometer attaches? My bus rpm stays at 0 so doesn’t seem connected trying to fix
There are as many different tacho types as there are GM engine models,
It could be cable driven if it's very old, you could see a cable attachment male thread either on one of the accessory drive pads, or even on a right angle drive taken of the blower drive.
If it's an electric tach it could have a tacho gen, looks like a gauge sender, screwed onto one of the accessory pad tach drives, or it could have an inductive sensor screwed into the flywheel housing with the tip very near the ring gear, or it could be screwed through the gear train housing with the tip near one of the camshaft drive gears. Electric tachs can also be driven from a terminal on the alternator, that's a whole other world of pain with many different systems.
I have an 8.2L that revs well over 4,000 I’m trying to find some kind of way to cut it back to 2,750 they’re set at the factory to 3,000 but when I got it there was no high speed governor, anyone know how to turn these down? The assembly looks very similar if not the same as this one.
I’ve backed out the big nut till it was pulling the idle down, and it will still peg out my 4K tachometer. I’m at a loss.
8.2 L were a real mess, some had mechanical only governors some had electronic only governors, and some had a fixed speed high rpm governor with electrics on top of it. Make sure the rack linkages aren't jamming at some point in the tubes leading from the valley into the heads.
The idle on my crown bus is too high, is it the same procedure for the sideways 671? The bus has always idled around 1,000 rpm and i feel that’s way too high...
Same
limiting speed governor
I have 2 6v71 engines on my boat, can’t get them to start.. purged the air in the lines, new filters, fresh diesel. I can get it to pop and sound like it’s about to cold start but won’t catch and go. Is there some sort of shut off or purge valve I’m missing on these old engines? Both doing the same thing
Fuel, air, compression is all it takes. Air flapper shutoff possibly closed. Better make sure the rack isn’t stuck if it’s been a lo g time since you started them.
If this is still relevant, what is your fuel consumption per hour?
صح عليك
I always have to rev my engine to go into reverse. Is that normal? 1971 mci7 871
No
Can you do a video on how to turn up the voltage regulator on mci 7. I know there is an adjustment, but I don't know where to start
u can turn a 6 or 8 v 71 up around 3 grand and it run all day just fine
No u cant..if u do it eventually destroy your motor.....
Two stroke DD will take High RPM all day long. as a matter of fact, they will actually live longer. They are not happy being lugged down. I grew up with these engines and have owned several. We opened the governors up as far as they would go on every one of them. Never once had an issue with it.
I was just about to ask if you upgraded the valve springs to be on the safe side if you could run 71 up to 3k, not sure based on what he said bout the trans if the driveline will be happy but the engine should be ok not so?
A 6V53 comes from the factory set to no load of 2800 RPM.
@@robertm3079 You're correct, 71 series engines like operating in the upper range of the governor, a Detroit doesn't like lugging down , but don't set the max no load speed higher than 2300 RPM.
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