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I’ve wanted to make this video for some time. In fact I’ve had these fans sitting at the shop for almost a year waiting for this video to be made. I know that I screwed up some of the terminology but I’m hoping the concept of how a torque converter works is conveyed in this video. I look forward to your thoughts.
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[quote=”spelunkerd” post=52016]It’s a great feeling to have it all come together conceptually, and the new video does just that. The one area I still had some problem with is the dynamics of how the stator works. I found an excellent pdf file written by Toyota, explaining it in much more detail. I’ll try to append it at the bottom of this note in case anybody else wants those details.
The problem with using air fans as a conceptual tool is that the direction of flow across the stator doesn’t come from the impeller, it comes from retrograde return flow after it bounces off the turbine. Remember that the whole system is sealed, so total oil flow has to balance out.
The second critical point is that the direction of oil flow across the vanes of the stator change, depending on relative impeller and turbine speed. When the speed of the impeller is much greater than the turbine, flow is largely a vortex, with oil coming off the turbine at such an angle that it hits the concave faces of the vanes of the stator, locking it up. Those locked vanes redirect oil flow to give the input of the impeller a torque boost.
When the turbine speed rises, the dominant pattern of oil flow becomes more rotary, which changes the angle that the oil hits the stator. This time, the oil flow hits the convex back of the stator vanes, and return oil is already flowing in the right direction to optimize impeller input. If the stator were fixed in that setting, there would be a performance failure causing poor engine performance and overheating at highway speeds. So, the stator is designed to freewheel when pushed in that direction.
For a longer and much better description of what I said above, read the following pdf file.
Great post! Thanks for the info.
What really surprised me is the fact that the torque converter unit was a sealed (welded?) unit and Eric had to use angle grinder to split it. Are all torque converter like that?
Eric had to use angle grinder to split it. Are all torque converter like that?
I think a plasma cutter or oxy/acetylene torch cut would have been a more efficient method than doing all that die grinding… but it got the job done.
[quote=”vgs8606″ post=52225]What really surprised me is the fact that the torque converter unit was a sealed (welded?) unit and Eric had to use angle grinder to split it. Are all torque converter like that?[/quote]
Yes they need to be sealed so that they will hold in the fluid.
Do remember those two speed Hondamatics?
They had converters that were so good you did not have to change gear even on a hill. They were also very thin. What made them so much better than the conventional fat ones?im building an off road trial dune buggy my question is could i use a torque from a car in a dune buggy with a 18hp Briggs and Strattons engine side shaft and what would be the best one to use the buggy only wights 300 to 400 lbs its the orange one im putting trail arms on the rear and bigger ones on the front any on can help would be great thank Alex_huntzinger@yahoo. com
Alex,
A car unit wouldn’t work on your application. They make centrifugal clutches, like the ones in snowmobiles, that would be better for you. Some people call these torque converters also. Once you get the right springs and weights in, they are great. You can get them from go cart part suppliers. You will need the horsepower, tire size, final gear ratio, and weight of the vehicle to pick the right one out. You then fine tune with different springs and centrifugal weights for max performance. Looks like a fun project. When you get it done, try studding the tires and riding it on the ice.i know what you are talking about i have one on my trike it really nice but im looking for more power with out a bigger engine and 300 hundred dollar cvt i am vary mechanically inclend and i have the tools to do what ever i need to do but do they have a torque converter that has all the fluids self contand or what car have cvt in them like the Mitsubishi landser
two questions. i have a 4 speed in my truck. (47re) im putting down about 1200ft/lbs at the wheels. should i be focused on getting a billet stator or would a normal low stall stator be ok? also, i have my TCC locking in the top of 1st gear under heavy throttle. so it locks at 18Mph and stays locked through 1-2-3-4/od shifts and adds a great deal of acceleration, this only happens under HEAVY throttle, normal driving the TCC stays unlocked .
im trying to save money and the normal stator is considerably cheaper.I have a few questions out of curiosity…
1. The case of the converter is sealed to keep the fluid inside etc. Ok. But is there any possibility the fluid could get degraded and cause the converter to work below the factory parameters?
2. What about the clutching element you’ve presented in the video – could it get worn out and fail?
3. What is the estimated mileage of the torque converter under “normal” driving conditions? I.e. is it possible for the converter to fail after going about 90 thousand miles?I think the torque converter in my 2001 Toyota Corolla is having issues during low speed bumper to bumper traffic the transmission would slip slightly. I say it’s the torque converter because off throttle I feel the torque converter would disengage but when I go accelerate it would slip slightly.
I tried to change my driving style and ease on throttle very carefully and it would won’t slippage but I’ll be moving very slowly because of it. One time went to merge in a lane in the city with heavy traffic so it evoled alot of creeping the tranny didn’t drop a gear instead the engine revved up and it felt like it shifted up or torque converter locked up suddenly this caused the whole car to shake when it happend. The transmission would shift fine after when driving on the highway or 30 or 40 MPH city speeds.
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