17' Hamm H235 / H10i broken vibr motor

Owner purchased at auction. Primary issue: vibrator motor casing has broken in half at the mounting flange 2 times. I think the first motor was reciently replaced before auction. My thinking about possible causes:

1. Operator is smashing the motor against something. (Unlikely)
2. Some sort of excesive or strange vibration. Because the 2 vibrators are not in sink? Or maybe because they are in sink?
3. Faulty castings.
4. Overtorque/undertorque of mounting bolts? Both vibrators seem to be in ok shape. ie. (No excessive bearing wear) Motor to vibrator mounting surface seems to be true. Can hydraulic pressure brake a motor off at its mounting flange? Im leaning towards #2. Anyone have assembly procedure for vibrators? Im interested to know how they are synct. Thanks for any help, Joe

Have any pics of the damaged motors?

To orient you regarding the photo above, The mounting bolting flange broke off from the main body of the housing on both motors.

I’m wondering if the shaft in the motor is bottoming out. Have you looked at the end of the motor shaft or inside the coupler for scaring?

There are 2 types of drives. One a splined coupler shaft with male splined nubs on the motor and the imbalance shaft. The other is a 3 finger lovejoy style with 3 fingered nubs on either end. The lovejoy were changed over to the splined. Now, if some dummy runs the splined nub onto the tapered motor shaft with an impact, he probably split and expanded the nub. This binds the slip joint spline and puts excessive stress on motor. Usually you get a slobbering shaft seal. I have not seen any broken off as you describe without grinding em off on a high curb.

If you turn the imbalance shaft CW & CCW, can you hear and feel the weights stack up and oppose. There are swinging weights shared on the shaft with a bolt and bushing to allow stacking and opposing. If you can't discern the difference, it might be worth pulling the drums out from under. It's not a bad job, just messy. German metric fittings if your looking for caps and plugs. Regular plastic caplugs work too.

Vetech63 said: I’m wondering if the shaft in the motor is bottoming out. Have you looked at the end of the motor shaft or inside the coupler for scaring? Click to expand... On this model there is 1.25in of clearance between the 2 shafts. And the vibator does not have excessive though-out.

funwithfuel said: There are 2 types of drives. One a splined coupler shaft with male splined nubs on the motor and the imbalance shaft. The other is a 3 finger lovejoy style with 3 fingered nubs on either end. The lovejoy were changed over to the splined. Now, if some dummy runs the splined nub onto the tapered motor shaft with an impact, he probably split and expanded the nub. This binds the slip joint spline and puts excessive stress on motor. Usually you get a slobbering shaft seal. I have not seen any broken off as you describe without grinding em off on a high curb. Click to expand... This one seems oem splined with coupler. Yes, only snaped motors Ive seen, (before this) the Op bashed it with something... etc.

funwithfuel said: If you turn the imbalance shaft CW & CCW, can you hear and feel the weights stack up and oppose. There are swinging weights shared on the shaft with a bolt and bushing to allow stacking and opposing. If you can't discern the difference, it might be worth pulling the drums out from under. It's not a bad job, just messy. German metric fittings if your looking for caps and plugs. Regular plastic caplugs work too. Click to expand... I don't think I understand you 'stacking and apposing' . I have one vibrator pulled as there are other issues as well. (Pre-auction Oil leak, broken bolts, damaged threads, damaged driveshaft housing, etc) I do want to know if the weights of the 2 vibrators should be in sync or 180deg out of sinc etc. I bet they where in sinc and in my mind Im thinking there should be 180 out of sinc to cause the drum to vibrate properly.

Joseph Burt said: On this model there is 1.25in of clearance between the 2 shafts. And the vibator does not have excessive though-out. Click to expand... I installed the new motor with the cupler and it has .25in if clearance.

Solved: the vibration assemblys had been installed 'in-sync', after resealing and fixing everything, I installed the vibratiin assemblies 180deg out ov sync. Running great. Thanks to all who tried to help.