grease fitting on power steering

[Gary G.]

I have a 75 coupe with power steering. On the end of the steering ram is a grease fitting. I have read conflicting information regarding this fitting. Should it be greased, in not, why not. What is its purpose?

Thank you for any input.

[Michael J.]

Re: grease fitting on power steering

I hope they are supposed to be greased, I just greased the one on my '66 that has power steering.

[Paul O.]

Re: grease fitting on power steering

Gary the fitting they say not grease is the one on the power steering control valve. If it is greased it can and usually will cause the internal seals to start leaking. You will then have a leak and lose all you power steering fluid even when sitting idle. Paul 18046

[Joe L.]

Re: grease fitting on power steering

I have a 75 coupe with power steering. On the end of the steering ram is a grease fitting. I have read conflicting information regarding this fitting. Should it be greased, in not, why not. What is its purpose?

Thank you for any input.

Gary-----


The grease fitting on the ram is to provide grease for the ram's ball stud. It can be greased without causing any problems.

[Joe L.]

Re: grease fitting on power steering

Gary the fitting they say not grease is the one on the power steering control valve. If it is greased it can and usually will cause the internal seals to start leaking. You will then have a leak and lose all you power steering fluid even when sitting idle. Paul 18046

Paul-----


I think the main problem with greasing the fitting on the power steering control valve involves OVER-GREASING. The purpose of the grease fitting is to provide lubrication for the control valve's ball stud. I usually inject only 1 or 2 pumps worth of grease and have experienced no problems.

[Gary G.]

Re: grease fitting on power steering

Thank you gentlemen. Joe, I usually lightly grease the ram, and I have greased the control valve slightly over the years. Sometimes, there is too much conflicting information on various forums, which leads to confusion. I know that if you pump too much grease into any fitting, you can do damage.

[Jim T.]

Re: grease fitting on power steering

My original owner 1970 has power steering and I am the only person that has performed this lubrication since my car was new. I always lubricated this fitting like Joe L. has mentioned as well as the other lubrication locations on the front end with a hand held manual pump grease gun. No problems with the control valve doing this routine greasing. Only thing I have done to my power steering system is install new power steering fluid hoses and I have replaced the seal in the power cylinder.

[Michael W.]

Re: grease fitting on power steering

OK- here's a counterpoint. A unit in good condition does not leak any fluid. If grease is gently pumped in every now and then, where does it go and why is more needed? How would a person know that it's full? I understood that these units were greased initially at assembly and were NOT to be touched again. Some vendors state that warranty will be voided if any grease is added.

[Michael J.]

Re: grease fitting on power steering

Gary-----


The grease fitting on the ram is to provide grease for the ram's ball stud. It can be greased without causing any problems.

Whew!! I just did 1 pump with my hand grease gun, and so far so good, no leaking I can see.

[Joe L.]

Re: grease fitting on power steering

OK- here's a counterpoint. A unit in good condition does not leak any fluid. If grease is gently pumped in every now and then, where does it go and why is more needed? How would a person know that it's full? I understood that these units were greased initially at assembly and were NOT to be touched again. Some vendors state that warranty will be voided if any grease is added.

Mike------

The lube fitting on the power steering control valve is on the adapter side of the valve and lubricates the ball stud. The ball stud is theoretically "sealed" but so are the ball joints, tie rod ends, and other components with ball studs.

The seals on none of the above are really all that efficient and as the steering and suspension are "worked" some of the grease inevitably works its way out.

Also, if the intention were that the power steering control valve was "lubed for life" at the time of manufacture, then why install a grease fitting here or, even, provide a tapping for a grease fitting to be later installed? All GM valves that I've seen, PRODUCTION and SERVICE, have an installed fitting.

[Michael J.]

Re: grease fitting on power steering

Mike------

The lube fitting on the power steering control valve is on the adapter side of the valve and lubricates the ball stud. The ball stud is theoretically "sealed" but so are the ball joints, tie rod ends, and other components with ball studs.

The seals on none of the above are really all that efficient and as the steering and suspension are "worked" some of the grease inevitably works its way out.

Also, if the intention were that the power steering control valve was "lubed for life" at the time of manufacture, then why install a grease fitting here or, even, provide a tapping for a grease fitting to be later installed? All GM valves that I've seen, PRODUCTION and SERVICE, have an installed fitting.

I agree, why put a grease fitting on a sealed unit? Also, the grease, over time, heat, and shearing stresses, becomes very thin, which contributes to needing to be regreased. There is an excellent exploded diagram of the cup that is greased in the CSM in the power steering section too.

[Michael W.]

Re: grease fitting on power steering

Mike------

Also, if the intention were that the power steering control valve was "lubed for life" at the time of manufacture, then why install a grease fitting here or, even, provide a tapping for a grease fitting to be later installed? All GM valves that I've seen, PRODUCTION and SERVICE, have an installed fitting.

So why the horror stories and threats of denied warranty? Are there that many ham fisted owners and garage mechanics? Never mind, I know the answer to that one.

[Gary G.]

Re: grease fitting on power steering

Mike,

You are probably right, too many guys with an air powered grease gun have ruined many fittings on cars over time. I agree with Joe also, why put a fitting on something that does not need one. The warranty could be voided on just about anything if you aren't careful.

[Jim S.]

Re: grease fitting on power steering

The original control valves had a zerk fitting and a ball stud boot with a purge slit to allow excess grease to leak out of the boot. This boot design was very good in that you could not overfill the ball stud cavity. The excess just regurgitated on the floor.

During the 1970s there was a concerted move on the part of GM to have all their cars with "lubed for life" tie rod ends, ball joints, and other chassis fittings. The Corvette control valve was included in the edict. So I assume the control valve was packed with a better grade of grease, the purge slit was eliminated, and the zerk fitting removed.

Now the problem arises with rebuilt control valves. A lot of cores have zerk fittings. I am quite sure that the ball stud boots all come without purge slits. So I am equally sure that a lot of rebuilt control valves are overfilled with grease because they come equipped with a zerk fitting. Worse, the grease has no place to go but back against the hydraulid seals in the valve, or the excess causes the ball stud boot to burst.

Jim

[Dick W.]

Re: grease fitting on power steering

Most, if not all, rebuilt valves have an "off color" grease in them. If they find any other grease in them most vendors will deny warranty.