Power steering pump pressure, 450().

[Cle Elum John]

450() crawler, built in 1968
I am trying to get the power steering working better. The brakes and steering still require a lot of force to activate
What I have done so far:
Put new seals in the slave cylinders
Adjusted the brakes and clutches using the method in the factory manual.
I put a pressure gauge on the pump as shown in the service manual and it got interesting.
At idle to 1200 engine rpm, the gauge is just a blur because it is jumping around so much.
Above 1500rpm it settles down somewhat and but still jumps between 150 and 200psi.
Factory manual says adjust for 300psi. Would that max, minimum or average pressure?

Couple questions: Should I be using an inline orifice in front of the pressure gauge to damp the pressure fluctuations?
I was surprised the pressure jumped around as much as it did. Is this indicative of a bad pump? Am I missing something obvious?
Has anyone rebuilt one of these pumps? It looks like it will be somewhat difficult to remove. Are parts available?
The service manual says the pump has a pressure adjustment screw on it. I have not been able to locate the pressure adjustment screw on the crawler. The area is covered with a lot of grease and muck. I may be turned around, looking in the wrong place and it may be partially hidden by the alternator. Am I missing something? Should I be able to adjust it with the alternator on the crawler?

If anyone has worked on the steering pump and cylinders, could you fill me in on the details? Are these typical issues? Any advice?
Thanks for any help
John

[Jim B]

I don't have a 450 manual so can't be sure exactly what it says or shows.

A gauge with a snubber can smooth rapid fluctuations in some cases. Fluid filled gauges can be better as well.

If the manual says adjust to 300 psi that would be the ideal (maximum) set point.

The adjustment screw may require removing a plug to get to it (this is according to a 450B manual, again I don't have the 450 crawler service manual SM2064).

If there is so much grease and muck in the aera around it that you can't see things, I suggest a good pressure washing. It will help see things and if you do need to open it up you want the area clean as not to get crud in the wrong place.

Just to be clear does your pump have a separate reservoir mounted above it? If so, what is the condition of the filter in the reservoir?

[Cle Elum John]

Thanks for the reply. I was hoping to get some more insight on the bouncing pressure in relation to the health of the pump. Is it worn out? Should I be thinking of a rebuild? I am going to put snubber on my gauge, reset everything, and see if there is any functional improvement.