New gaskets for the Catalyst
First up this week at Old Tacoma Marine Inc, we ordered gaskets for the Catalyst‘s valve cages from Omni Packing & Seal Co. They don’t many take orders for the “sandwich gaskets,” which were originally asbestos with thin copper shielding surrounding the asbestos, because it takes a long time to make them and they’re expensive and one-time-use only. They are true to the Washington design, though, and they seal really well, so it was worth the extra time and money.
Sending out the guides
The Catalyst‘s engine was originally rated to run at 450 rpm. It’s been overloaded for many years, but now the new owners are committed to returning it to the 1932 specifications. This means unloading the engine to the point where it can be run at 450 rpm without overloading the engine.
To achieve this, it’s best to ease into it by catching up on the maintenance: as the engine is sped up, problems that go unnoticed at 350 rpm become critical at 450. A common problem is too much clearance in the cam follower guides, due from wear. The signal for service due is a knock, made by the follower hitting the guide at cruising speed.
To service the cam follower guides, you send them out to be honed straight and round. Then you have the cam follower (not the roller, but the crosshead like part) built up using flamespray, then ground down to leave .0015″ clearance. Then you put it all back together and start testing.
Suck, Squeeze, Pop, Blow
We got a funny shirt from Whitworth Marine, reminding everyone that all four-stroke diesels need to do is suck, squeeze, pop, and blow.
Check out Whitworth Marine Services, you East Coasters.
Grinding Catalyst Valves
Unfortunately, one valve was bent, which lead to lots of investigative inquiry. It turns out that the valve seat depths vary on the Catalyst from cage to cage. Without getting into blueprints, we chose to make all the cages extend the same length as the shortest one, which was .425″ from the gasket surface to the bottom.