C1 steering box grease fitting

[Don Izzo]

has anyone used the corvette central steering box grease fitting to grease their steering box. If so can you tell me is the fitting simply a replacement side plate bolt with a grease fitting tapped into the head, or is it a grease fitting that threads into the top filler hole? Anyone know what size fitting to use? Thanks!
Don

[mikemccagh]

Re: C1 steering box grease fitting

i just remove the plug, pump grease in and replace the plug. guess you could drill and tap a spare plug for zerk fitting and inject it that way but fear ya might blow the seal. mike

[Jim T.]

Re: C1 steering box grease fitting

I bought a assortment of attachments for my hand pump grease gun from Sears some time ago. It has a rubber tipped connector that can be screwed onto the grease gun and sealed in a bolt hole to inject grease. Also came with a pointed end connector . Don't know if the adaptor kit is still available from Sears, however it may be available from a auto parts store.

[Joe R.]

Re: C1 steering box grease fitting

Don,

The C1 steering box grease fitting is a 1" 3/8 bolt that has been drilled and tapped with a grease fitting. You simply remove a bolt on the housing and insert the 3/8 bolt, grease the box and then replace the original bolt.

Regards,

JR

[Clem Z.]

Re: C1 steering box grease fitting

i would also use another drilled bolt along with the grease fitting bolt as a pressure relief so you can see when the cavity is full and to prevent pressure build up. grease guns can exceed 1,000 PSI in pressure

[Stephen P.]

Re: C1 steering box grease fitting

The releif bolt would be a good idea. I'm not familiar with the C1 steering box, but made an adapter for my 65. Drilled a small hole through the length of the bolt and then drilled a slightly larger hole in the head of the bolt and tapped it for a grease fitting. I tried to pump and check often to make sure I wasn't building up internal pressure, but a small amount backed out when I removed the fitting. Took about 30 minutes to make the fitting, since I already had the parts. Don't try to drill through a grade 8 or higher strength bolt. Get a softer steel.

[Jim Sloan]

Re: C1 steering box grease fitting

On reading the various posts on the subject of the steering box for C1's, I have a question. What is the lubricant you are using. When you talk about having a "grease fitting" put in it suggests you are using multi-purpose grease from a grease gun. I am assuming the same as you would use when lubing the front suspension grease fittings. Anything I have read about says that you should be using 80/90 E-P gear lubricant, that you pour into the box through the threaded plug hole. This lubricant is liquid, not a thick grease like chassis lube. In the "Corvette Servicing Guide (1953-62) it says to use "Steering Gear Lubricant". In a Winter 1994 Restorer magazine article by Joe Calcagno on 53-62 Steering Gear Overhaul, he says "I believe most of the failures in the steering boxes are caused by a failure of the owners to check and maintain the proper level of gear oil in the gear box. The gears need a hypoid lubricant commonly called E-P lubricant (Extreme Pressure) or what most of us call 90-weight gear oil". As you would actually pour this in and not pump it in with a grease gun, would this not be the reason that there is not a grease fitting there from the factory. I am using the 90 E-P in my 60 and am wondering if this truly is the correct lubricant for the box.

[John M.]

Re: C1 steering box grease fitting

Jim,
You are correct that the original lube was 90 wt gear lube. C1 steering boxes have had a tendency to leak for almost as many years as they have been around. The boxes were subject to a lot of heat from the driver's side exhaust manifold and the box tended to leak from both the lash adjuster cup on the bottom of the box and from the sector shaft seal. The original seal was a leather seal, and was only marginal at holding back the lube. Modern spring-loaded lip type seals
have almost completely eliminated the sector shaft leak, but the lash adjuster cup is still a tough one. The lube leaks out around the threads, and while usually not to severe in it's quanity, it is annoying to have a few drops of lube on the floor of your garage every time you park the car! I have found that the liberal application of a non-hardening gasket sealer (AKA, Permatex),on the threads will stop the leaks. The side covers on these boxes almost never leak, and if they do, they are easy to sand flat and re-seal with silicone sealant.
There are however, a large number of people who have opted to put a grease in that will not run out. Although, this was not the original lube, John Hinkley has a GM document dating back to 1958 (if I remember correctly), which reccomends this method of repair of leaking boxes. There have been those who argue that the grease tends to channel and not provide the protrction of gear lube, but there are many who have used this type of lubrication for many years with no problems.

Regards, John McGraw

[Jim Sloan]

Re: C1 steering box grease fitting

Thanks for the explanation John. Yes, I do get some leakage from my steering box. So the grease you are talking about is common chassis lube grease? If so, now I can see the logic of having a grease fitting on the box.

[Clem Z.]

Re: C1 steering box grease fitting

back in the 50s when racing corvette the lube would run up the steering column and end up in the drivers lap. using chassis grease solved that problem. nowdays i would use grease with moly in it as it was not available back then