Thread: Gasket issues

Over the last couple of days I had to deal with a gasket issue, and my experience may help others.

About a week ago I noted that I had oil leaking from the LH front Warn free wheel hub. I found that it was leaking because the bolts holding it to the hub were loose. I tightened them, but found it still leaked - obviously the looseness had damaged the gasket. So a couple of days ago, I pulled the bolts out. This hub has two main parts, the body, which only serves to space the mechanism out beyond the end of the stub axle. The outer section, about two centimetres deep, carries the operating mechanism and half a dog clutch that is screwed onto the other half of the clutch (splined to the stub axle, and carried in a roller bearing) by the operating 'knob' (actually it is recessed).

The entire hub is cylindrical and the same diameter as the original drive flange. It has two gaskets, one between it and the hub, and one between the two parts. It was the latter that was damaged (saving me the trouble of removing the whole thing - split pin and undo the big nut). Both gaskets are standard hub gaskets.

Now I have a good supply of these, having bought half a dozen of them about six months ago. Just a matter of finding them (only about half an hour!), wipe off the oil and remove the bits of the old gasket.

Not quite that simple. The new gaskets, all of them, were about 2mm too small, both the big hole in the middle and the spacing between opposite bolt holes.

While it is possible that they were made too small, this seems rather unlikely. What had almost certainly happened is that they had shrunk. This possibly would have happened about three weeks ago when we had temperatures in the shed in the fifties with single digit humidity, but may have just been living in a generally dry climate.

The solution is to soak the gasket in water. I tried boiling water to speed the process up, but it took overnight soaking to do it. Got the thing back together today, and did a test drive - no leak, but as the gasket dries, the bolts will need checking for tightness.

No, at least on this application. The problem with sealer is that you have problems getting it off - and remember you should replace the gasket whenever you have it apart.

I tend to use sealer only when the surface is damaged, or very occasionally when I don't have a gasket. Paper gaskets are easy to make, although they do take time and it is not always easy to find suitable paper. An exception to this policy, but it isn't a paper gasket, is the rocker cover gasket on the 2.25, which I seal to the rocker cover, as there is nothing to make sure it does not get misaligned and cause a leak.

When assembling paper gaskets I always put a smear of grease on each surface.

John