Center Diff Locked up
#1
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So I finally got my modded engine set to go in my jammin crt.....did about 3 high speed passes and noticed an increase in power...then, bam..no power to my front wheels. Diff fluid was seaping out of my center diff on the front side. Damn. Opened it up and found my spider gears had shifted over wedging themselves in the diff case. Ifailed to pry them loose, and even if I did Im sure theres some stripped gears within them so Id have to replace them.
What causes this? I had just rebuilt the diffs and had 30k fluid in the center....Inoticed the screws holding the case together werent as tight as they could have been...they didnt appear to have backed out any, but definetely no stick from the locktight i put on them when i put it back together. Can theenginecause this with added power? Its a k4.6 with a port and polish job. Is my fluid to heavy?
Just want to know what I need to change so this doesnt happen again, or an upgrade I need to make so I dont blow another center diff. Id take a pic, but the lady took the camera to a baby shower. Thanks for any advice.
What causes this? I had just rebuilt the diffs and had 30k fluid in the center....Inoticed the screws holding the case together werent as tight as they could have been...they didnt appear to have backed out any, but definetely no stick from the locktight i put on them when i put it back together. Can theenginecause this with added power? Its a k4.6 with a port and polish job. Is my fluid to heavy?
Just want to know what I need to change so this doesnt happen again, or an upgrade I need to make so I dont blow another center diff. Id take a pic, but the lady took the camera to a baby shower. Thanks for any advice.
#2
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The diff cases wear out over time from the pounding, sudden jarring (especially from on power landings). As you change your oil in the diffs during routine maintenance, check over the diff housing. If the slot the gears/shaft slide into, replace it. It's cheaper to replace the plastic housing than the plastic housing and the messed up gears.
I dunno how much power your motor puts on, but I run a monster brushless setup that has instant power and I've noticed I need to keep an eye on the diff housing.
I dunno how much power your motor puts on, but I run a monster brushless setup that has instant power and I've noticed I need to keep an eye on the diff housing.
#3
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I dont think it was from too much power, just a kneejerk assumption since I had just modded and installed the engine....I went ahead and ordered another center diff to install.....thought maybe i should drop my diff fluid from 30k to 10k? Im thinking this issue was the reason I wasnt seeing much power or speed.....had difficult time setting gear mesh (maybe the assumed rubbing of gears was actually the diff gears causing resistance), and the extra noise. Never ran an rc with a center diff before......so I wasnt sure if the noise was normal or not.
Eager to get the diff in and try it again...still havent had a chance to truly grade the engines performance after the mod....cept for the fact that it starts easy and idles well.
Eager to get the diff in and try it again...still havent had a chance to truly grade the engines performance after the mod....cept for the fact that it starts easy and idles well.
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The diff weight fluid shouldn't have caused diff issues. It only acts as mechanism to equalize power between the wheels. You should adjust the diff fluid based on what handling characteristics you want.
I don't have my setup sheets in front of me, but I think I'm at 20k.
I don't have my setup sheets in front of me, but I think I'm at 20k.