Demon V8 water pump

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rrocky

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Hi all, the O ring that sits on the pump shaft how does it seal the water in the pump? does it seal with water pressure? I cannot figure it out any info welcome. thanks all Peter (Australia)
 
Sorry for jumping in I have modeled the block in cad software and I am having a hard time to get both idler gears to mesh with the crank and cam gear .Do I need to adjust something to get both in? One will work fine but I cant seem to fit both ?Thank you sir .
 
Not sure why but they work in real life. Could maybe be an error in tooth count?
DSCN1865.JPG
 
Sir could you verify a few numbers for me .? Thank you sir.
 

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Could be wrong here but shouldn't the driver be 1/2 diameter of the cam gear i.e. 0.52085, not 0.5417...?
Either that or visa versa on the cam gear.
 
Numbers look good. Must be the way the gear teeth are drawn. The second gear is optional so I wouldn't spend alot of time worrying about it. If you machine the block to the drawings they will work.
 
I think that the confusion comes from the gear diameters specified is the OD of the , gear. The pitch diameter, where the teeth touch is different.

The OD of a gear is equal to (N+2) / DP and the Pitch diameter is equal to N X the DP, where N is the number of teeth and DP is the diametrical pitch.

Thus for the 48 tooth gear the OD is ((48+2) / 48) which is where the 1.0417 dimension comes from. But the Pitch diameter is equal to (48 /48) or 1.0000. Same thing applies to the 24 tooth gear which equals a Pitch diameter of 0.5000.

Thus the ratios of the pitch diameters is the 2:1 that you were expecting.
 

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