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crankshaft sensor rebuild?

So my crank shaft sensor is starting to slip and causing serious lack of power and loss off efficiency.  I got a quote on the part but the cheapest i found was $325 usd.  I know you can rebuild a starter and an alternator and so i don't see why i can't rebuild it.  If anybody else has any experience with this pleas let me know.

Question by abadfart    |  last reply


I need to buy or fabricate a strong crankshaft for a strandbeest-like glass robot.

I'm making a walking robot out of glass based on Theo Jansen's strandbeest leg design. Fabricating the crankshaft has proven an odious challenge. I'm looking for a source where I can buy either a complete crankshaft to my specs or parts from which to fabricate my own. It needs to be about 30" long, with 6 crank arms (offset 120°, therefore 2 at each angle), throw on the crank to be 1". My original design was for a 1/2" diameter shaft, which is necessary if it's going to be glass, but if metal the shaft diameter could probably be smaller. The video here shows the crankshaft I made, but I don't  really trust it.http://instagram.com/p/x8xcPeyn-1/?modal=true  The prototype leg:  http://instagram.com/p/wewqr1yn6a/?modal=true

Question by bandhudunham    |  last reply


Hand powered boat propellor? Answered

I am trying to build a boat for a physics project, and i wanted to try building one that used a propellor instead of the usual paddlewheel or oars that other students have used.  I bought a 2-blade trolling propellor from Walmart, and i plan on attaching it to a crankshaft via a 4:1 belt drive ratio (so with every rotation of the crankshaft, the propellor spins 4 times). Two people will be turning the crankshaft , and the boat itself is stocky with a flat bottom and pointed end. Is this even possible, and will it actually get the boat to move at a reasonable speed? ("Reasonable" meaning rowboat-ish speed)  I included a quick sketch of what im talking about, and a picture of the blueprints to the civil war submarine that I got the idea from, just for proof of concept. 

Question by masterbuilder    |  last reply


Lawn mower blade hub.

I'm trying to figure out how to get the blade hub off of the bottom end of the crankshaft on my TroyBilt - Honda powered mower. There is no set screw that I can find, and it doesn't appear to be a thread off. There is a key, but I can find nothing that suggests how to get this thing off. I need to take it off so I can change the bottom crankshaft oil seal. This is a Honda GCV160 engine. Thanks for any input.

Topic by thebilger    |  last reply


Lawn tractor magnito for wind power generation?

Lawn tractors have AC alternators built around the crankshaft with a rectifyer to DC. Would a wind generator using this for the power generator work, and how much power would it make?

Question by whitet6    |  last reply


A way to make a real k'nex fully automatic gun

UPDATE: I have begun to construct a gun out of this. It doesn't shoot very far in the video because I am using a motor to power it, but once I complete it I'm hoping that it'll be pretty powerful.Video: http://www.youtube.com/watch?v=LJbFasz1eAgOriginal Post: It occurs to me that you could use a crankshaft with a motor or wound up rubber-band to push and then subsequently pull a firing pin in your gun. This coupled with a hopper that can push rounds into the chamber, and you would have a truly fully automatic gun, as opposed to a ton of single-shots all on a chain (which is cumbersome to load).I'm not good at all at actually designing k'nex guns (not anymore anyway), but I did put together and example of a crankshaft, and have attached photos and videos to this topic. The actual crankshaft at the back of the example could easily be elongated so that you could have your firing pin travel farther, and if you put that axle on a small gear attached to a larger gear which is on another axle with a rubber-band or motor to turn it, you could get at least 20 shots from the gun. Reloading it would also be really easy, as you could have a crank to turn the main axle allowing the rubber-band to build up potential energy once again.Sorry if this is confusing, I'm not the best orator or typer as it were, but I think the pictures will be a lot easier to understand.Sincerely,Black LeopardVideo: http://www.youtube.com/watch?v=Gbmm3BaAQgc

Topic by blckleprd    |  last reply


Piston heads- simple easy designs/ light materials?

I'm looking for an apropiate design soloution for making my own stirling engine piston heads. I plan on using O'rings for the seal and joined them to piston arms which in turn are connected to a crankshaft...please advice Once I'v built I'll upload pictures/tutorial (over the next few month)

Question by dubpunkdub    |  last reply


A few questions for recumbent bicycle makers

Okay, as the title says, i've got a few questions for anyone who's made a proper recumbent bicycle. First: in the way of moving the handlebars back, how do you attach a bicycle chain sprocket to the top of a fork tube? is it welded? or is it a special type of sprocket with a sort of crankshaft keyway (like engine crankshafts have keyed sprockets for their timing chains) this is obviously to relocate the handlebars further back or under the rider so that you can lean back (as most recumbents allow) Second: if you're to put a larger tire on the rear of your bike (for example, a small (50-500cc motorcycle) rear tire), how would you go about converting the chain link sizes. most motorcycle tires have a shorter link distance, and look like their links are sort of squashed together as opposed to bicycle chains. would you find a way to put a larger toothed sprocket on the rear tire or put a smaller toothed sprocket on one side of an intermediary and a larger toothed on the opposite side? If I have any more i'll post them, these are my pretty basic "burning questions" of recumbent making.

Topic by TheMadScientist    |  last reply


Wheelchair Wheels

I'm a wheelchair user and I would like to change the side wheels and rims with a bike  geared wheel and push handles.   I need someone, brighter than me, to  work out how to combine the crankshaft and back wheel into one unit? If this could be done, I would extend the pedal shaft to become handles which I could push with my arms. Don't know if that is clear.. I've tried to add an image here, but Instuctables just not uploading anything!!! If you have any idea about the wheel idea, I would be grateful to hear? Many thanks Richard

Topic by DickyMac    |  last reply


Can Non-Hybrid Cars Get 100+ MPG Today?

  We're not talking about hybrids here; our topic is cars powered by the basic IC-engine that relies on gasoline and not electric motors. Today's gasoline engines are not designed to combust/burn gasoline efficiently. Even with the advent of using high pressure fuel injection techniques that are computer controlled, we still fall short of the mark. Partly because liquid gasoline can't burn, only gasoline vapors burn, and there lies our problem. The same goes for injecting the high pressure droplets of fine-mist liquid gasoline that enters the engine cylinder using our current nozzle ejector technology, it doesn't all burn at the same time! Engine designers assume that these droplets are instantly vaporized by the engine's hot cylinder walls, and then instantly explode/combust when ignited by the sparkplug. Not true, up to 2/3 of the fuel isn't vaporized and doesn't combust until later on in the cycle. The 1/3 that gets almost-instantly vaporized and burns will do so within the several thousandths of a second (Fig-1) it has before the piston moves down its 1/2-stroke (out of today's 4-stroke cycle) completing the engine power-portion of its cycle. This releases power and tremendous heat which indeed vaporizes the remaining ~2/3 of our fuel from its liquid droplet form, but too late. It essentially does so when the power stroke is almost over or the piston is just about ready to move into its up-stroke (2nd stroke of our four stroke cycle) phase. So, because of poor vapo-timing we have 2/3 of our fuel virtually wasted by exploding at near the bottom of the power stroke. This incorrect explosive timing, which happens to most of our fuel, imparts very little energy into the crankshaft because its effective "moment" (a product of explosive force and radial-component distance from crankshaft center) is insignificant by then. Various attempts at adjusting the combustion timing spark hasn't made a significant difference. Even though ~2/3 of the fuel is now exploding and providing a huge force, its small "influence" arm distance is rapidly diminishing to zero, and any huge downward force times near zero arm-length is still zero. Some clarification here, technically thermal-efficiency is not improved, pretty much all of the gasoline gets combusted today. That means the energy of the fuel is almost totally released, but not effectively used. The problem is the timing it takes to convert fuel-injected gasoline droplets into vapor to combust at the correct engine rotational time and extract that expended energy. If you did the math for any size engine rotating at say 3200 RPM, you would find that a 4-stroke engine can only extract that energy from combustion during one of the four strokes. And the time it takes to make that stroke happen is only about 9.4 thousandths of a second or 9.4 milisecs (msecs). Now picture the piston just below TDC, all its valves closed, under pressure and containing all the fuel and air it needs to combust. At this point our deadly cocktail has about half of the 9.4 or about 5 msecs to complete combust after the timed sparkplug ignites it. The half factor exists because the max portion of our power stroke (moment arm) occurs at the mid-stroke of the piston sliding down and turning the crankshaft. If all of our fuel isn't combusted by then, the moment-arm or distance from the piston-center to the crankshaft quickly reduces to zero. Again, only vapors combust within a healthy 2 msecs (Fig-1), while fuel droplets take a relatively long time (>5 msecs) to vaporize before it can combust. Unfortunately nature is stubborn and vaporizes ~2/3 of our injected fuel droplets only during roughly the second half of the power stroke. So this huge amount of energy gets wasted because even though the forces of combustion are huge, its moment arm is rapidly approaching zero. Infinity times zero is still zero! Engine designers/engineers have been plagued by this phenomenon ever since the creation of the 4-stroke gasoline or Otto cycle engine. We need to improve this intermittent combustion/explosion process by combusting all of our injected fuel at the correct timing sequence. This is accomplished by injecting only vaporous fuel which will produce ~3X the power we now get. Another way to state this is, for the same power that we now get from a gasoline engine, if we burned the fuel correctly, we would only need 1/3 the fuel consumption to get 3X the current MPG.

Topic by RT-101    |  last reply


How do i fix this zafira problem

Help zafira w reg keeps losing power almost feels like it's braking?i have a w reg 2000 zafira elegance 1.8 petrol and i have got a problem with it losing power big time at low speeds and quite serverly when cruise at 60-70 mph it almost feels like the brakes have been applied then all of a sudden it picks up and flies off. i've had the engine managment light come on so had it put on the computer at main dealer they found code p0100 and p0505 which they charged £250 to tell me and convert the air flow sensor (allegedly as i don't see any sign of work done) .then thay said i need a new throttle body and iac valve new mass airflow sensor and pipes new crankshaft sensor new camshaft sensor plus a new ecu but can't quarantee that will fix it so what do i do pay the £3500 for them to try that or plead for help on the internet for ideas on possible solutions so here i am please could someone help

Topic by msc    |  last reply


is it possible to make a paper engine that runs off of hydrogen if it really sturdy and cylinder is lined with tin foil.

Ok so i have this edea to make a small two stroke engine out of paper and run it off of hydrogen witch i will make with a large battery and water like a fuel cell. But anyways ive allready built the piston and teh crankshaft and the encasing well most of it but i wanted to get some opinions on it can anyone help me? i should put on here that its not just a single sheet of paper thick um each component is 10 sheets of paper glued and compressed over 24 hours but also im thinking that if i lined the cylinder with tin foil it would stop the paper from burning and also the explosion will be very very micro sized probably 2x times smaller than a fire cracker and the compression will not be much of a problem because it works more off of the just the force of the pop. Ok so um the paper is yes just ordinary printer paper you can get at walmart for $2.50 but i cut out the shape i am making about 10 to 12 times sometimes 15 even and glue them all then stick it under a couple boxes of clay i have that are about oh well idk but allot of wheight and when its done each peace is about 1/6 of and inch thick so basicly about the thickness of chipboard.

Question by mrn    |  last reply


Have a DT50 watercooled yamaha,that I recently (6 weeks ago) bought ,ran perfect, now wont start ?

Have tons of  spark,clean carb,fuel runs out the fuel line,when un pluged from the carb. It as a small 6 volt battery,that was checked and is putting out more than 6 volts,checked the switch on the kickstand,even un pluged the switch and tried it with the ends pluged together ,eliminating the switch,no diff... when I pull the plug I can run fuel into the plug hole replacing the plug with tons of spark ,key on,lights on dash lit up and nothing.tried removing the side cover ,put a socket on the crankshaft nut holding the lflywheel on ,with an impact driver ,spun the nut off after a number of attempts with locktite.never once even fired.it has points, if the points are closed,can it have spark at the plug? if it has spark,why wont it even fire?checked all the wires for anything un pluged and have spun all the connectors  ,hoping   for continuity. has compression ,as much as a 50 can have,when it came home you could rotate the kick starter by hand and it purred,Havent checked the switch on the handelbar that has 3 positions.only when checking for spark ,noticed saturday that when the plug was out and grounded and sparking,when you switched it to the off position and kick it over the first 1 or 2 kicks it would spark then no spark till you switched it to the  on position.next move is a big long downhill,or a mandrel to drive the flywheel,via the holes in it with pins sticking out of a disk driven by the impact driver. will investigate the points and confirm there opening. replaced plug with new correctly gaped one

Question by JoeR140    |  last reply


How powerful of a motor do you need to run an alternator? Answered

From questions I have read and step by step’s I have read a question came to my mind. How powerful of a motor do you need to run an alternator? I checked the Delco Remy alternator series from 10SI in 37 Amps, to the 40SI durable brushless model, in 240, 275, and 300 Amps. All their performance charts show rpm’s at the alternator not the motor. The pulley on the crankshaft is considerably larger than the pulley on the alternator, giving you more rpm’s at the alternator than at the motor. All their performance charts show rpm’s from 1200 to 8000 rpm’s. All their performance charts show at 3000 rpm’s you get 13/16ths of max power. The last 5000 rpm’s only gaining 3/16ths of power. The thing is none of the performance charts say the horsepower to drive the alternator. I decided to approach the problem from a different direction Typical alternator efficiencies are in the 54%-60% range. Brushless alternator efficiencies are in the 60% 70% range. A typical 12v 60 Amp alternator produces 720 watts at 55% efficiency. It needs just 1310 watts to drive it or a little under two horsepower at 1492 watts. This does not account for mechanical efficiency of connecting the alternator to the motor. With this in mind a three horsepower motor should drive a 12v 60 Amp alternator. This is just an educated guess but I would like a horsepower chart. 720 watts would do well at charging a battery bank while you sleep; however I could not run my microwave and charge batteries at the same time.

Question by Josehf Murchison    |  last reply