SpeediSleeve Tech Day
October 21, 2001 - St Charles, IL
When you have a really bad oil leak in the rear hub, and a new set of seals and gaskets doesn't stop it for long, then you need a better fix. Here on the left you see the problem of a groove worn in the real axle housing surface where the hub seal rotates. On the right you see the solution of a renewed surface. And in the photos below you can see how it's done.
Click for larger pictures, average 30KB.
Two cars to do today. One has splined hubs with REALLY TIGHT knockoffs. The other has bolt-on wheels and gets a little head start. You know it's serious when you have TWO guys working with hammers. First you remove the wheel, then the brake drum, then the axle half shaft, and then go after the lock tab washer securing that BIG octagonal bearing nut.
These large octagonal nuts are supposed to be REALLY TIGHT, but often the DPM (dreaded pervious mechanic) may not have had the right tool for the job. This requires a deep tube 1-61/64" octagonal socket. Not your every day hardware store item, but readily available through British parts distributors. Sometimes the big nut may come off quite easily, and on close inspection it may be obvious why. Without the proper tool, many a DPM has resorted to hammer and chisle to R&R this part, and the results are not pretty. Good idea to replace this one.
Then you have to pull the bearing and hub off of the axle housing, sometimes not so easy. If the big nut was loose the bearing may have been moving around a bit and worn itself loose on the housing, so you might pull it off with your fingers. Other times you can bust your hump with crowbars and it won't move. This is when it's nice to have the right tool. A large slide hammer will remove even the most stubborn hub with just a few quick strokes.
Once the hub is off you can clean up the housing and get a good look at the situation. In really bad cases you can hook a fingernail in the groove left by the rotating seal. Other times the damage may be barely visible, but tearing up new seals anyway. The easy fix for this is a Speedi-Sleeve from Chicago Rawhide, or a Redi-Sleeve from Federal Mogul. They both bear the same part number, and are for all practical purposes identical. The part is a thin steel tube (0.009" thick) with a flange and a tearaway groove. The outer surface is properly ground to provide the smooth new running surface for the seal. The part costs about $40, and the weight is about 1/5th of an ounce, so that makes it nearly as expensive as GOLD. Please don't drop it or step on it.
Each sleeve comes packaged with a shallow metal cup that can be used as an installation tool on on a stubby shaft. That cup does a nice job of protecting the sleeve in storage and transit, but in our case the cup isn't deep enough to reach down over our long axle hub. In a pinch any kind of rigid tubing that makes a close fit over the sleeve may be used as a driver tool. Instructions say to use an epoxy steel filler to fill the wear groove in the shaft is it is particularly deep. I don't suppose you would ever find one worn that bad on an MG axle, as the new sleeve can easily bridge a groove up to 1/32" wide. It is a good idea however to clean the mating parts and apply a thin film of sealant/adhesive either to the shaft or to the inside of the sleeve before installation. Loctite thread adhesive works well for this, and then you're well assured that the new sleeve will never work loose or leak internally.
A piston ring compressor also works well as an installation tool, and is adjustable for for any diameter. Just hold the sleeve and the driver tube straight and square with the shaft, and tap gently. The sleeve is so thin that it stretches to slide over the shaft relatively easily, even though it is technically a tight interference fit.
A word of caution here, do not push the sleeve on too far. Stop as soon as the outside edge of the sleeve is past the shoulder on the axle housing. Also cutting through the flange with a side cutter before you press the sleeve into place may be easier that cutting it after it's in place. You have to cut a notch in the flange most of the way down to the groove in the sleeve, being very careful not to scratch the working surface of the new sleeve. Then pull the flange radially away from the shaft to tear the flange off, leaving only the thin sleeve in place. And there you have it, a spanking new seal surface with just the exact micro finish to hold a very thin coating of oil to lubricate the new seal.
As usual, when there's a break in the action the extra hands get to kick a few tires and talk shop about some other subjects. The wheel bearings are R&R'd in the hubs in order to replace the rubber seals. Then the large octaconal bearing retainer nuts get torqued up to 150 lb-ft and secured with the loctab washers. Hub and axle flanges are cleaned, and new o-ring and paper gasket seals are installed. In short time the hubs and brakes are all reassembled and brake shoes cleaned or replaced. We do a quick test of a faulty fuel level sender unit, get the wheels back on the cars and the shop cleaned up. Did we remember to do that? Well at least the tools were picked up, and we now have two more MGA with secure hub seals, dry rear brakes, and human caretakers with large grins on their faces.