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Discussion Starter #1 (Edited)
TH350. dropped the pan and the magnet looks like abstract art. so i pull the pump apart and its wasted. the outer gear actually machined the pump body away. My book says .001-.005 clearance between the gear and pump body, actual is .045! Any idea what caused this. pump was a reman unit when i build the trans the first time and only has about 500 runs in an mid 11 sec bracket car. Common sense tells me to at least have the converter checked or flushed. has anyone had any luck with converter flushing?


 

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I used to flush converter everyday when I worked at a trans shop rebuilding th400 in plow trucks, never a problem. I have 2 ideas about whats going on there. the first one is cavitation, the other one is that your running really high pressure and the outside of the gear isn't getting enough lube. My last though is the pump drive in the converter is not running square.

I typically use a dremel and cut a very tiny lube slot to feed oil to the outside gear on almost all my trans builds. Seems to help with stopping galling at high pressure on street cars. I more or less just nick the surface enough to leak a bit of oil to the outside of the gear. like 10 thou deep channel.
 

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I used to flush converter everyday when I worked at a trans shop rebuilding th400 in plow trucks, never a problem. I have 2 ideas about whats going on there. the first one is cavitation, the other one is that your running really high pressure and the outside of the gear isn't getting enough lube. My last though is the pump drive in the converter is not running square.

I typically use a dremel and cut a very tiny lube slot to feed oil to the outside gear on almost all my trans builds. Seems to help with stopping galling at high pressure on street cars. I more or less just nick the surface enough to leak a bit of oil to the outside of the gear. like 10 thou deep channel.
Just a note to make sure you do this on the pressure side of the pump.

Jim
 

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It may have also suffered from a dry start or had contamination enter it at one point. Once the galling starts it just keeps grinding itself to death until it looks like yours.


Hutch
 

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you mention using a "reman" pump. I have seen some of the reman pump gears with slight flashing on the edges that is left from the manufacture process that needs to be cleaned off before use. I use worn 320 grit paper to remove the flashing
 

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That is one of the reasons there is a filter installed in the case on a 350.Also th350 recycles excess oil pressure and volume back into the suction side of the pump.When there is contamination it keeps going thru the gears unfiltered eating the gears and pocket up.
 

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Discussion Starter #7
I dont see how it could hvae gotten contaminated. Its an external cooler, and its a track only car that sits in the garage when not on the track. What does everyone think of flushing the converter?
 

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Contamination could have been from grit being left in the trans or in the converter from sloppy rebuilding practices not necessarily from an outside source.


Hutch
 

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looks more like the pump was never alligned with a pump allingment
tool.
just side loaded the gear to to the pump body and away it goes and picked up and kept on going.
one stuffed pump.:(
 

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The only thing I can see with a misaligned rear half would be a pump that would be a real bastard to put into the case. Not sure if you could bugger it that bad as to have pump gear wear because of it.


Hutch
 
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