Failing Power Steering Pump Cause Knocking Sound?

[90LS400Lexus]

I mentioned before that my 91' LS had a knocking sound that concerned me. I had thought it was a rod, but I was told this was unlikely on the 4.0L engine. I later had a major clunking that turned out to be my fan bracket bearing. I thought maybe that was the part causing the noise. I had that replaced with a OEM Toyota part, but the knock was still there. Its been like that for awhile, but its getting more pronounced. It can only be heard sometimes at idle, but mostly when accelerating lightly when the engine is between 12-1600 rpms. I cant hear it unless the radio is off. I have a leaking PS pump and wondering if this noise could be coming from the worn out pump, or?

Thanks for any info.

[AzHotLS]

No, your valves need adjusting. My 90 did the same thing, knocking under slight acceleration. After reading through threads here, I came up with the determination that it's the valves.

[90LS400Lexus]

Thanks... I saw your post on the other site too... thanks.

Will it hurt to continue driving it like this? I imagine its quite time consuming to adjust the valves since the covers have to come off? It will need valve cover gaskets soon anyway, but I was wanting to wait at least a few months to do this.

[AzHotLS]

I don't think it will hurt anything driving it like that. I'm not an expert so don't take my word for it, but I drove my 90 like that for quite a while with no appearant side effects.

Valve Cover Tutorial:

http://www.lexls.com/tutorials/engine/valvecover.html

Valve Adjustment:

http://lextreme.com/valve_clearance.html