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Thread: Main Bearing Damage (R.I.P)

  1. #11
    460rogers
    did you prelube before starting?
    maybe he used the assembly lube in the green can with the clover on it,or is that lapping compound?
    what did the crank look like?

  2. #12
    HOSS
    I thought of lapping compound also. But upon closer inspection it seems that the guy dropped the hand cleaner in the lifter valley.
    In all seriousness it appears that the galleys were not thoroughly cleaned. Cam lube couldn`t have caused that. Maybe someone dumped a quart of contaminated oil in the bitch. You know, like the quart you dip the drill bits in! You know that tanks need to be cleaned also. If he hot tanked his buddies Scout rims before then you found the culprit.
    Whatever it was it went through the entire system and it was a hell of alot of it. Thrust bearing was not the problem. Wanna know a neat trick. To set thrust bearing clearance just hit the crank back and forth from front to rear a few times. If it still feels too tight by touch then hit it a few more times. Oh, and rings take about 15 to 20 mins to seat. If someone tells you different then tell them to go read another ****in` book.
    Tractor Pull,,,,,,,,now thats a read.

  3. #13
    flat broke
    Hoss,
    I mainly mentioned the thrust bearing issue because he is planing on putting together one hell of a piece for the next motor and with that HP, the clearance issue (not the actual thrust bearing clearance) with the driveline could easily damage another bottom end if it was setup too tight, not allowing room for the impeller and shaft to walk forward.
    Chris

  4. #14
    1979tarva
    with the experiences that i had i know now if you dont do it yourself then dont do it because someone will mess it up for you. machine shops dont know anything at all about motors even if they race or people claim to know there good. it could be anything that caused that to happen to your motor and it sucks that it did.

  5. #15
    Moneypitt
    Any shit that the rod bearing kicked out into the pan would have been caught in the oil filter. The damage on the mains, that lines up to the oil holes isn't from shit coming through the system, the filter would have stopped that, what you're seeing is unchamfered oil holes. After the crank was ground, the sharp edges of the oil holes wern't re-chamfered. I've seen it dozens of times. All it takes is a little ball to get rolled up, and from there its like a snow ball effect. From there the shit goes to the rod, and usually spins the rod bearing. If one oil hole was left with sharp edges, I'm betting they ALL were left that way, mains and rods. Again, the shit that came out of damaged rod bearings could not get back into the system unless you don't have an oil filter. Also check the OIL PUMP for damage as the shit goes through the pump BEFORE the filter.........Moneypitt

  6. #16
    Hotcrusader76
    Originally posted by flat broke
    One thing you might want to consider. If it wasn't a f'd up assembly, and everything was together correctly (tollerances etc), perhaps the debris from the thrust bearing taking a beating worked its way through your oiling system.
    If you don't have a little front to back clearance bettween your driveline and the front of the pump, you can have this problem. When the pump is loaded the impeller and shaft will sometimes walk forward. If there is clearance in the coupler on the input shaft, no big deal. If there is NO clearance then as the shaft moves forward, it loads the crank and the thrust bearing sees excessive wear.
    The only reason I even thought of this was because I remember that you had just setup a new rail kit for the event. It's hard to say from the pics of the thrust bearing if it is really worn, or that is just the color out of the box. I've seen thrust bearings come brand new with some copper showing, and others with a gray color on the thrust surface.
    Whether or not it is the source of your contamination is debatable, but if it was, that is how it got that way.
    Check this fitment on the new motor install to make sure the coupler has some room to move on the input shaft before bottoming out on the front of the pump.
    Chris
    I will go no further in this reading....only because Chris hit it on the head! The rail kit I used was the same one previous from the last motor. But when I installed the new motor, I also installed a new driveshaft from Rex Marine which pushed the motor forward almost 1.5" (I had an old driveline then had to upgrade because of the spicer joints).
    Now when I moved the motor forward I would bet that the pump had little to no clearance, not even dawning on me that I could trash the thrust bearing. Maybe this put a load on the crank which hurt #7 rod and then KKAAABBOOOYEEE it all went south from there.
    I think I will be asking for some assistance on the next install with regards to setting the motor's stance in the boat.
    Awesome point of veiw Chris. I didn't even think of that.....and I KNOW for a FACT!!!! that the clearnance is tight on that shaft going into the pump, meaning it's nearly completely seated (no forward or aft movement)
    ok....I'll continue reading now.

  7. #17
    Hotcrusader76
    Originally posted by flat broke
    Hoss,
    I mainly mentioned the thrust bearing issue because he is planing on putting together one hell of a piece for the next motor and with that HP, the clearance issue (not the actual thrust bearing clearance) with the driveline could easily damage another bottom end if it was setup too tight, not allowing room for the impeller and shaft to walk forward.
    Chris
    Chris....you're right. If and when the next motor is bedded down I will be sending the set-up to Jack over at MPD for some pump work. I will also be inquiring upon some High-HP help on ensureing the pump and driveline live to 900+HP....specially when I reach 600lbs of torque at 3000RPM....yikes!

  8. #18
    Hotcrusader76
    Yeah...well...it's all hard to tell.
    Info, Hoss, o58.....you're all right. Something went through the block quick and dirty. It's all effect not cause.
    Some awesome points were given and I respect everyone's experiences for what it's worth.
    See ya'll on the river.....no paddles this time

  9. #19
    Wet Dream
    Originally posted by Hotcrusader76
    See ya'll on the river.....no paddles this time
    Sometimes those are you BEST FRIEND.

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