Steering rack - do you know what this is for?

[petergoudie]

I'm in the process of putting new seals into a leaky power steering rack on my 7MGE MX-83 Cressida. I just removed one of the boots and noticed in the rack shaft there is a hole. I can poke a length of wire down it into and along the shaft (see the photos). My questions are:

(1) Is this hole to allow air to pass through to the other side when the rack is wound to full lock. I'm thinking the boot would blow up like a ballon if the air could not go somewhere.

(2) How is the ball joint on the tie-rod shaft lubricated? I noted there was some oil in the boot but I don't know if it was oil for lubrication of the joint or leakage of power steering fluid past the oil seal.

[Sam_Q]

ok I can't help you much other than to say that those ball joints are lubricated like wheel bearings are, they are packed and then held in there with the rubber boot.

I can't think of any reason for that hole being there

[petergoudie]

Thanks Sam. As it is a power steering rack there is an oil seal in the end of the housing so it is fully sealed. This is why I'm thinking the hole is a vent to allow air to pass through somewhere otherwise the air inside the boot has nowhere to go when it is extended or compressed.

[TRD-12A]

Yeah for sure it,s a pressure relief hole kind of the same as a water pump one if the pressure gets too high for watever reason the relief allows the pressure to come out without destroying anything else