Actually, we balance the crankshaft first THEN add the flywheel, clutch pressure plate and harmonic balancer and balance the entire rotating assembly together. This video clip is entitled "balancing a crankshaft", not "balancing a rotating assembly". Thank you for your question.
regcer: This video is for an in-line 6 cylinder engine. Typically, in-line engines do not require bobweights for balancing. V-motors would require bobweights to counteract the push/pull of the rod/piston assembly at a given degree.
@hazmat440 I know this is an old thread, but I will throw this out there: I don't know for sure, but I would use a timing light, activated by the crank bouncing when it spins. If the drive could only pivot up and down, the crank would bounce up and down. The timing light would show the position the crank is at when bouncing, and you could grind a bit to lessen the bouncing effect.
You don't need bob weights on a 180* crankshaft like this one. You balance the crankshaft first, then add the flywheel and balance it; if you balance them as an assembly then when you replace/machine the flywheel as part of a clutch replacement you would have to remove the crankshaft and re-balance the whole assembly again. By balancing each part of the assembly separately you can replace the flywheel later on without changing the balance by just balancing the flywheel before it's installed.
the crank for a 6 inline is usually pretty balanced on its own , try the same thing with a v6 or v8 crank and it prolly jump off the bench without bobweights still dont understand why they didnt used bobweights but thats just me not knowing the type of balancing unit or basicly wat im talking about i guess
Well Im no ASE certified master machinist but uhm wheres your flywheel and crank pulley at? i was taught they are balanced as one bolted together rotating assembly. so are you just half assing that balance job? or do you know something i dont?
+John Warner (Doc) inline 6 and v12 have all their forces (1st, 2nd and 3rd) already naturally balanced they don`t need andy counterweightinh, meaning you only have to consider the differences in mass due to slight imperfections during forging/casting/milling of the crank. Because of that as long as you do proper balance of the conrods and pistons all the rotational and reciprocating masses will be balanced.
Um, you are not quite right there. Even though Trimadian has no idea, even you should know that an inline 6 with 120deg spacing has two sets of pistons part way up, and part way down when one set is at TDC. But you are correct in saying no bob weights.
@Duckyistrippin ok dudley-do-right. youre really getting heated over this arent you? tell you what man, youre sooooo cool and im such a piece of shit. do you feel better now?
I cannot believe this guy using an angle grinder in a room that has all that expensive equipment in, plus the grinding particles will work its way under the rollers which supports the crank on the balancing rig. Very poor working practices.
The crankshaft is as divine as this music!
Actually, we balance the crankshaft first THEN add the flywheel, clutch pressure plate and harmonic balancer and balance the entire rotating assembly together. This video clip is entitled "balancing a crankshaft", not "balancing a rotating assembly". Thank you for your question.
Lol. Love the poster of the GT500 hanging up in a Jag shop.
regcer: This video is for an in-line 6 cylinder engine. Typically, in-line engines do not require bobweights for balancing.
V-motors would require bobweights to counteract the push/pull of the rod/piston assembly at a given degree.
@hazmat440 I know this is an old thread, but I will throw this out there:
I don't know for sure, but I would use a timing light, activated by the crank bouncing when it spins. If the drive could only pivot up and down, the crank would bounce up and down. The timing light would show the position the crank is at when bouncing, and you could grind a bit to lessen the bouncing effect.
Digital balancer, I'm jealous. We're still hobbling along using an analog Stewart Warner balancer. Works great, just needs more manual maths.
its amazing that the crank wa close enough to just grind off come weight.
You don't need bob weights on a 180* crankshaft like this one. You balance the crankshaft first, then add the flywheel and balance it; if you balance them as an assembly then when you replace/machine the flywheel as part of a clutch replacement you would have to remove the crankshaft and re-balance the whole assembly again. By balancing each part of the assembly separately you can replace the flywheel later on without changing the balance by just balancing the flywheel before it's installed.
gotcha, i appreciate you explaining. im still learnin
the crank for a 6 inline is usually pretty balanced on its own , try the same thing with a v6 or v8 crank and it prolly jump off the bench without bobweights
still dont understand why they didnt used bobweights but thats just me not knowing the type of balancing unit or basicly wat im talking about i guess
ClassicJaguar, with a poster of a mustang in the shop :P
I thumbed up twice only for this coooooooooooooool tune. :D
Well Im no ASE certified master machinist but uhm wheres your flywheel and crank pulley at? i was taught they are balanced as one bolted together rotating assembly. so are you just half assing that balance job? or do you know something i dont?
Nice one! I have done this in college. But you got it right at first attempt?? actually we have to this manually I mean we did calculation first.
Is it ok if you use bobweights for an inline 4 crankshaft ?
That is if you want to be super precise with the process...
Thanks !
what were u doing with the big grinder?
What I don't understand is this;
If you balance a 'bare' crank like that, why doesn't the weight of the con-rods throw it out of balance?
+John Warner (Doc) inline 6 and v12 have all their forces (1st, 2nd and 3rd) already naturally balanced they don`t need andy counterweightinh, meaning you only have to consider the differences in mass due to slight imperfections during forging/casting/milling of the crank. Because of that as long as you do proper balance of the conrods and pistons all the rotational and reciprocating masses will be balanced.
Um, you are not quite right there. Even though Trimadian has no idea, even you should know that an inline 6 with 120deg spacing has two sets of pistons part way up, and part way down when one set is at TDC. But you are correct in saying no bob weights.
ty for this video even i dont have a car
isnt 50 tdc better than 48. ?
Removing material (weight).
is that windows 98?
clearly he knows alot that you dont
'
why need it balance on crankshaft,,,
dont feeling crankshift while drive on the road,,,
the motor is only move move and not crankshift
@Duckyistrippin ok dudley-do-right. youre really getting heated over this arent you? tell you what man, youre sooooo cool and im such a piece of shit. do you feel better now?
Выколите мне глаза после того что я увидел.
nm i see what it's doing now. derr
Music but no talking bummer man
I cannot believe this guy using an angle grinder in a room that has all that expensive equipment in, plus the grinding particles will work its way under the rollers which supports the crank on the balancing rig. Very poor working practices.
great video, too bad music sucks