The seals
I think I'm well-known on another popular TDI link for my cylinder head work...
There are two popular seals for the cam. VW uses the silicone style springless seal since about 2002 on their cams.
The problems with the usual spring style seal is that the spring holds the seal's knife edge hard against the running surface. Eventually, you eat a groove into the cam running surface. If you ever replace the seal or oftentimes, just disturb the #1 cam bearing cap, the seal will not find the same groove and it will leak. The recommendations are that you can replace a spring type seal with either spring or silicone, but you cannot replace the silicone with the spring-type.
The springless silicon seals have a different sealing system and approach. The crankcase pressure is what holds the sealing surface of the seal onto the running surface of the cam. The seal lays flat in relation to the cam. This makes no groove into the cam. The seal has VERY LONG life and is easily refit and reused. Once you've seen the difference, you're sold for life.
The springless seal POLISHES the cam to a mirror finish.
But it does require careful installation or you will roll the sealing edge over on itself.
I definitely use the Silicone style seal.
In order to properly install the seal without problems, I first install the seal BACKWARD (cup out) onto the camshaft. This swells the seal out to the size of the cam bearing surface. Wiggle it in and it spreads the seal very evenly and that opens it up, just enough for an easy fit.
Then, turn the seal around, reinstalling it the proper direction, with the flat of the seal out and the cup in. Push it squarely into the cam cap and tighten.
The manufacturer recommends leaving the seal alone for 4 hours before running the engine. Seriously, I haven't had a problem with my technique, but I would suggest sticking with manufacturer's recommended procedure.
Frank
I think I'm well-known on another popular TDI link for my cylinder head work...
There are two popular seals for the cam. VW uses the silicone style springless seal since about 2002 on their cams.
The problems with the usual spring style seal is that the spring holds the seal's knife edge hard against the running surface. Eventually, you eat a groove into the cam running surface. If you ever replace the seal or oftentimes, just disturb the #1 cam bearing cap, the seal will not find the same groove and it will leak. The recommendations are that you can replace a spring type seal with either spring or silicone, but you cannot replace the silicone with the spring-type.
The springless silicon seals have a different sealing system and approach. The crankcase pressure is what holds the sealing surface of the seal onto the running surface of the cam. The seal lays flat in relation to the cam. This makes no groove into the cam. The seal has VERY LONG life and is easily refit and reused. Once you've seen the difference, you're sold for life.
The springless seal POLISHES the cam to a mirror finish.
But it does require careful installation or you will roll the sealing edge over on itself.
I definitely use the Silicone style seal.
In order to properly install the seal without problems, I first install the seal BACKWARD (cup out) onto the camshaft. This swells the seal out to the size of the cam bearing surface. Wiggle it in and it spreads the seal very evenly and that opens it up, just enough for an easy fit.
Then, turn the seal around, reinstalling it the proper direction, with the flat of the seal out and the cup in. Push it squarely into the cam cap and tighten.
The manufacturer recommends leaving the seal alone for 4 hours before running the engine. Seriously, I haven't had a problem with my technique, but I would suggest sticking with manufacturer's recommended procedure.
Frank
