I really am beginning to think DSM is correct your answers have been slipping lately.

Take the easiest one first go to any salvage yard and buy an engine and ask them to run it for you on a stand and you will see them set one up on a stand with just a flex plate and it runs just fine. You seem to be forgetting what and internally balanced engine means.

Never mentioned anything about cylinders firing. What I said is firing impulses from one set of pistons are offest buy the other set of pistons coming up in the hole canceling most harmonic vibrations.

That is why the Fit can get away without running any external balancing mechanisims like some engines have.

How does an engine "go to pot" stick a reefer in the air intake? Come you can be more specific than that.

 

Balancing an engine is making sure the weight of the rotating mass is the same on all opposite parts so it rotates smoothly as with tire balancing; it does not take into account the imbalance from the firing of combustibles in the cylinders. Since the applied forces of combustion are all applied to the same side of the crankshaft there no way to offset those forces except with a counter rotating assembly or flywheel. tO EVEN THINK THAT THE WEIGHT OF OPPOSITE CYLINDERS CAN MAKE UP FOR THE HUGE FORCES APPLIED FROM COMBUSTION IS NOT EVEN CLOSE TO CORRECT. AND WHAT DO YOU THINK HAPPENS WHEN THE OPPOSITE CYLINDER ISN'T FIRING at 6500 RPM? Stand back, way back. Good Grief, Charlie brown.

And for those to want to say automatic transmissions have no flywheel I'll forgo the explanation why thats not correct by quoting FIT SHOP MANUAL pg 14-33 third sentence under Toirque Converter, Shafts, and Clutches:
"The entire torque converter assembly serves as a flywheel while transmitting power to the transmission mainshaft"
Its been a while but we have tried to run a Honda 4 cylinder engine without flywheel and it didn't without bucking like a bronco. The salvage yards we deal with always demonstrate engines for customers with a flywheel attached. If they didn't customer wouldn't buy it. Mostly the flywhedel goes with the engine and should be.

PS For the way younger generation 'going to pot' was the term for the result of visiting the outhouse, and of coirse had nothing to do with hallucenigenics. Well I don't thimk so. and yes, at 76 I slip a lot but not here.

 

What about hte vehicle that use a counter rotating assembly and the flywheel???? The fit needs neither. LOL plenty of Fit engines have been run on stands with JUST the flexplate and didn't tear themselves apart.

You don't seem to understand Internally balanced engines has your memory of their principals failed you? IF and it's just a suppose the Fit was externally balanced the new flywheeels and or the original flywheel would come with a balance weight or pad installed in them and would be installed in only one position to complete the balance.... but guess what stock Fits or the new flywheels DO NOT HAVE THEM therefore they are NOT included in the fit's balance package. Any spurious mysterious vibrations MUST BE coming from the new flywheel..... like for sure bro it is out of balance on it's own.

You keep skipping over the point that there are many members with lightened flywheels installed with NO MYSTERIOUS spurious vibrations and no problems what so ever??? What about them where did these pulses disappear to?

 

Having been a member of a few engine design projects,m I have plenty of backing from designers that flywheels are necessary on street engines that have to run at less than 2000 rpm. You miss the point - again. Lightened flywheels as much as 20% certainly are successfully done on engines where performance is especially important and where running below 1500 rpm isn't necessary. And where vibration isn't a drawback, on street engines that idle at 900 rpm. We've done them all.
But the fact is, as any engine manufacturer will point out, a flywheel is necessary to prevent the rotation of the crankshaft from being erratic.
If they weren't needed why do you think they are there? To add to the cosrt of manufacturing? Surely you jest.

 

You seem to be skipping over the members that do. Honda considers it a flywheel (torque converter in autos). What's the definition of a flywheel? We're not talking about a drive/flexplate.

The issue is detecting misfires which is a function of crank speed between power strokes. The symptom is misfires (codes) after lightening the flywheel. Seems like it serves a function, no? Kinda like a flywheel... Granted it's not as needed as in an engine without a balance shaft. Maybe your experience is from engines without crankshaft sensors...

 

Good questions....

afaik, most people who installed a lighter flywheel were the GD owners.... this might be one of the few (only?) GE owners who did also... gonna check 555's thread.

 

An engine rotates by the combustion force on the piston; its a lot like turning the crankshaft with a hammer. Every time the hammer hits the crankshaft it is rotated in a jerk. Each combustion is another jerk and the crankshaht sensor then transmits erratic impulses to the ECU. The ECU then being nothing more than calculations sends the wrong firing signals, that is misfires, resulting in more erratic rotation which the driver finds annoying. Not until the RPM rises more than 3000 rpm does the erratic applications get quick enough to smooth out the rotation.
Here's your "F".

 

Thankee...

Ignition timing is controlled by the camshaft position sensor. This is an electronic pick-up that sends a signal to the ECU corresponding to the camshaft position for the purpose of ignition timing. There is no "erratic" signal any more than there would be with a mechanical distributor unless your timing chain gears have stripped their keys.

The crankshaft position sensor was introduced with OBDII in order to sense "misfires." These are a function of the time it takes the crankshaft to turn. Small differences in partial rotation times are counted and stored. If these "erratic" counts exceed some threshold a misfire code is signalled. There may or may not be a misfire associated. If an actual misfire occurs, the rotation speed of the crankshaft is less for that part of the rotation.

The flywheel helps maintain a steady crank speed. Lessening its mass will result in more frequent differences in rotation resulting in flagging a misfire whether one has actually occurred or not.

You may have your "F" back... and some remedial reading material.

pissing contests between adults.... I need more beer.

 

Boy you are on a roll today spreading false and misleading information.

Pray tell please point out the camshaft position sensor on the Fit???????????

And it's really really the crankshaft position sensor that indicates when it is time to initiate the firing sequence.

 

Dude I wasn't talking about driving an engine down the street without a flywheel I said it could RUN to prove a point and again what about all the ones done successfully how are you accounting for them????

 

I seem to remember a few GE owners popping up in this thread back a ways
or maybe another flywheel thread so successful conversions to light weight flywheels on a GE are out there running fine.

 

I don't have a flywheel, just a clutch. I was about to purchase one from Jun, but they stopped producing them after having problems with the GE and said they were not going to delve further into the project as not beneficial for them. This is the same reason that there are not any super single clutches for the GE from the likes of ORC, Cusco, Exedy, Toda or ATS, but there are for the GD. J's Racing was trying to work on something with somebody for a flywheel for the GE, but it seems they have given up as well.

 

item 3 in the illustration: TDC pulser. phhhtdtp

 

Oh, that's what it was... cool. Hope your GE's problem has been resolved.

 

And I reply:
Precisely. You too get "F" for not understanding that is what I said if you agreed with loudbang. A flywheel is critical to the smooth operation of a 4 sroke engine due to the irregular application of combustion forces to the crankshaft
When the OEM weight is dropped by 20% or more misfiring is the result just as you say. Again, what did you say that I didn't?

PS I wrote some of the remedial material and it too says what WE both say about the need for steady crank rotation and why the balancing of an engine does not perform the function of a flywheel. I need to know so I can make sure my next class gets the message clearly. Perhaps I need to define erratic better.
cheers.

 

Like you the link doesn't work.

 

sorry if I miscommunicated, mahout. I agree with you (I don't agree with mr bang. he hoists himself regularly from his own petard.)

 

'Rotating' quite erraticaly, meaning jerking and bucking, it doesn't qualify as 'running' unless it idles for a minute by itself you can't even hang on 'running'.

 

They run for more than a minute on a stand with just the flex plate LOL. You still haven't said why SOME people can do it successfully on a GE.

 

Mahout has told you 3 times already...

The mass of the flywheels they installed was enough to keep the crank position sensor/ecu happy and/or other operating conditions are such to keep a marginally light flywheel from causing the ECU to throw a misfire code.

Either the crank position sensor is connected or it isn't. Codes are not appearing immediately leading one to believe it's connected correctly. Codes don't appear after they reinstall the OE flywheel. Connect the dots.