DIY Small Engine Dyno 2.0!

In this episode we massively update and upgrade the DIY small engine dyno!
If you're interested in making your own, check out this link here: dirtyelbowsgarage.etsy.com/li...
#smallengine #dyno #diy

[@trleith]

I found this because I was looking for electric lawnmower and string trimmer reviews that are actually informative. I don't care about volts. I don't care how you feel. I care about how much torque can be produced maintaining a "useful" RPM, how many VA we're sucking out of the battery at max torque, and how long the battery lasts when doing that, and maybe at half the max torque. Also benchmark against a "typical" gas machine. Something along these lines. You need a dyno for that and nobody seems to use one to review these machines. At least nobody I've found so far. Fuel flow measurement on a gas engine would be nifty. Your full blown dynamic test sounds about perfect. Great instrument, you're giving me hope of finding what I'm after.

[@rr1150r]

Nice build. I have a similar unit for testing my kart racing motors. I used a pressure transducer to measure the torque than the the load cell and a proximity switch for the speed sensor for rpm. I am working on an inductive sensor for rpm. Processing thru a raspberry pi. I also added a weather station chip to compensate for temp, humidity and pressure. I would love to collaborate on code.

[@frostyab7579]

is the pump pressure limited? if not, you should add a relief valve so you don't hurt yourself, high pressure subcutaneous oil injection can cause serious harm

[@michaelheinsler5441]

Great job 😁

[@terryvickers5986]

I would like to see some dyno ttesting on an engine equipped with a thunderstorm generator.

[@terryvickers5986]

In the early 70s in highs,chool we used a dynamic with a water brake hooked to a faucet to test 3 Hp Brigs and Stratton engines. With simple air and fuel flow guages, we were able to calculate the volumetric and thermal efficiency. At 5,000 rpm, they produced 5 Hp.

[@fernandohood5542]

Are there not sensors to measure oil flow and also electro mechanical devices to control flow? Is a torque arm really necessary?

[@driveitbreakitfixit7496]

Just some advice, should never have a filter on the suction side of the pump, that being said strainers are fine if there BIG ENOUGH. Filter should always be put in the return side to the tank. If not it can cause cavitation do to the lack of oil going to the pump witch will effect performance/readings

[@DirtyElbowsGarage]

This is great advice and you are right. Most systems are filter after pump. The main reason I routed the filter first is because this is effectively a single component system - there's no motor or valves or auxiliary components to protect. On dyno 1.0 I had a contamination issue that seized a pump and I wanted to avoid that happening again. And even though it's not the normal setup, I did do it with a suction based filter, it's got an internal bypass specifically to stop cavitation.

[@DriftCentral]

Can u make one for an eddy current hub Dyno?

[@markhoward4727]

Plus when he changes the filter, he’s going to dump all the oil out of the tank and system. He at least needs a ball valve between tank and filter housing. Gonna make a really big mess without one.

[@gd5625]

Do you sell just the Arduino sketches separately?

[@jimiandrix]

What would be the max rate for hp/torque ? Im interested in adapting this principle to harley v twin engines that outputs anywhere between 40 and 150hp

[@DirtyElbowsGarage]

This setup will handle up to 30hp as a combination of rpm and torque. For more power you'll need to up size just about all the components. 3000psi is a typical max so you'll need a pump that can flow 5x more oil, a flow control valve that can restrict that flow, then a new load cell for the additional torque - and all the associated mechanical reshaping to make this work. And, depending on reservoir size you might need to get into oil cooling, depending on time at max engine load. Quite a few hub style dynos are hydraulically operated using the same principles as this one. Finding the right parts to work together well is the trick.

[@jimiandrix]

@@DirtyElbowsGarage after a full day of research, i found out that there is no hydraulic pump units that would suit the requirements for these hp numbers... the principle is very good for small engine but isnt quite there yet for bigger ones ! I might turn to inertia dyno for my project

[@WickedWood]

What is the estimated cost all in for the mechanical parts to build this less the steel?

[@DirtyElbowsGarage]

I was able to get everything for just under $1000. Prices vary depending on shipping and where you can get the parts from. I provide sources but it's possible to swap in cheaper options.

[@WickedWood]

​@@DirtyElbowsGarage ok, thank you

[@topfuel15]

What is the software to see the graph ?

[@DirtyElbowsGarage]

That's Arduino's built-in serial plotter tool. It graphs the values you assign to it and you can toggle them on and off in the upper left-hand corner.

[@topfuel15]

@@DirtyElbowsGarage thank you!

[@NeMoC53]

Could this kind of setup be used to dyno a 30hp tractor off the PTO? Or is that too much ?

[@DirtyElbowsGarage]

In principle It would definitely work for that application. But to specifically make it work it would need some re-gearing to pick up pump speed compared to your PTO (also depends whether you have a 540 or 1000 rpm PTO) and also a rework of the attachment to the tractor so that the torque is transmitted properly.

[@NeMoC53]

@@DirtyElbowsGarage I’m going to look into this. I have an old 8N and you have inspired me. When I have a chance and my kids aren’t draining my pockets, I’m going to purchase your plans. Thanks for the reply. New subscriber….. out. 😎👍

[@DirtyElbowsGarage]

Thank you! And I also have an 8N!!! Great little tractor that just keeps going. Good luck and feel free to reach out anytime!

[@PurpleNovember]

Careful with the reactive forces of all that torque.

[@JohnsonPortWorx]

Is it possible for you to make me some of those parts. Being compensated of course

[@DirtyElbowsGarage]

Feel free to email me at [e-mail] and we can discuss more about what you're looking for.

[@jakub77]

for correct measuring power you need also flow meter :)

[@karldettling5981]

If you are building a mid-engined car i have the tooling you need to make it! Check out my car the dettling car car on youtube. If you want to produce the car i the tooling for sale to build them. It is the best constructed car in the world. And will cost you much less!

[@DirtyElbowsGarage]

Hi. The car I'm making probably won't match some core chassis layout and geometry features of yours so I'm not sure if that would work out. Even so, I respect and recognize the value of the tooling and if you'd like to talk more about what you have, feel free to email me at [e-mail]