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Discussion Starter · #1 ·
installed new pump on transmission, front end play is now .045.
can i stack two thrust washers or machine a new one from aluminum
to reduce front end play?
thanks
 

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Sure you can stack up 2 washers , just don't get too much thicker than .110" or you will be too far off the pump and the rings may fallout of the ring bore. This is only temporary as you needed to get this done tonite.

Hutch
 

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Discussion Starter · #6 ·
the washer i have now is .009 can if went to max of 0.011
that would leave me a front end play of 0.034.
is this acceptable or too much?
thanks
 

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Discussion Starter · #7 ·
disregard previous post
made a mistake on my initial reading of 0.045 now i am reading 0.025.
the reading of 0.025 is using a 0.09 thick washer without using gasket(0.016 uncompressed)
with gasket installed i should have theoretical end play of 0.041.
will this be to much end play
thanks
 

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Still a bit of a flopper. Make sure your hub has sharp splines at the back where it engages the mainshaft stop, if they are eroded away that will help, also you can put a hardened torrington shim under the washer between the fwd drum and the hub to get it to a more reasonable end play.

Hutch
 

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Discussion Starter · #9 ·
splines look somewhat sharp.
thought about putting washer their, was not sure if that was acceptable or not. guess i will go track some torrington washers down.
thanks for help
 

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Discussion Starter · #10 ·
finally found a .106 selective washer. made three passes this past saturday. transbrake held fine on first two passes. did not hold on third pass, noticed while i was staged that my pressure was 150 psi. just coasted down track back to pits and noticed pump pressure had dropped down to 20 psi.
when i pulled pump out noticed first piston ring was broke and ate
the area of pump bewteen ring landing and back face of pump.
i am assuming the ring came out of bore with this washer.
now i am not sure what to do now. place thinner washer and have a larger end play?
i just destroyed a 200 dollar pump, just hate for this to happen again. i have been building 400 for sometime now , and never had this happen before, mabye a rare occurance
 

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was it a cast iron sealing ring? i've used a .106 washer before.Did you put the drum on the pump or measure from the washer to the ring to see if the depth into the fwd drum was ok?
Like Hutch says you can put a washer under the fwd clutch hub to raise the drum slightly so that the washer thickness can be less...
 

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Discussion Starter · #12 ·
yes cast iron, no i failed to measure.
was unable to find washer to place under forward clutch hub
will measure next time though
 

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yes cast iron, no i failed to measure.
was unable to find washer to place under forward clutch hub
will measure next time though
ok... you might want to get some teflon rings on there,also on the centre support while you're at it. Higher pressures tend to push the cast iron ring hard into the drums.
Do an air pressure test and see how hard it is to turn with those rings on,then do another with the teflon rings......
 

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Discussion Starter · #14 ·
can not do an air pressure test with this pump anymore the ring land is to far gone. i am picking up another pump end of this week
so its possible pressure from transbrake could cause cast iron ring
to eat into the ring land on pump housing?

did take some measurements this afternoon
measured from top of washer to beginning of bore(bottom of chamfer) on front drum
had a distance of 0.187

then measured from back of pump to first ring land
had a distance of .270

which leaves a distance of .0835 between ring land and beginning of bore(chamfer) in front drum

0.0835 minus my front end play of .010 leaves 0.0735 of clearance
i would think this would be plenty.
 

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Get a new pump and use Teflon sealing rings. Cast rings have no place in racing transmissions with constant line pressure.
The old cast rings(20+years ago) used to be good but anything new seems as if they are made out of wood.

Hutch
 

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Discussion Starter · #18 ·
are these the type rings you are referring to
thanks


 
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