1978 GMC K25 power steering question?

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78k25JJL

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Jeff
Truck Year
1978
Truck Model
K25
Engine Size
350
Hello all, have a quick question regarding power steering pump lines I have a 78 gmc k25 and the threaded line going to back of pump and barbed line with clamp are both leaking 1 day old refurb pump. Does the threaded line to back of pump need and o ring? Do both lines going into steering box need and o ring? The flared ends on them look like there is no place for one. 2 leaks at back of pump itself and a little seeping on return line into box. Which lines need orings there is 3 hard lines and 1 barbed line which clamps on. Thanks in advance for any responses.
 

Old Guy Bill

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Truck Year
1978
Truck Model
K20
Engine Size
400
Did you get the right pump when replacing it? Later model pumps used O-ring fittings.
A ‘78 should be flared fittings on the pressure side of pump and both fittings on the steering gear box.
Don’t over tighten them and distort the flare.
The return line on the pump should have a worm gear clamp.
 

78k25JJL

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1978
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Engine Size
350
Pump is right same as 40 year old one, all hard lines are brand new does the clamp type matter? Maybe try 2 small clamps
 

78k25JJL

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Location
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Jeff
Truck Year
1978
Truck Model
K25
Engine Size
350
Only leaks when wheel is turned not at idle
 

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