| Diagram | Fig. 1 — Engine: Crankshaft, Connecting Rods, Pistons, Camshaft, Timing Gear · ref 17 |
| Subsystem | engine bottom |
| Listed in parts books | 1971–1973 |
Norton Timing Cover Oilway Plug
A small plug that seals an oilway in the timing cover of the engine's timing gear/oil pump assembly.
NME4591 is a timing cover oilway plug, a small threaded plug that seals off one of the internal oil passages machined into the timing cover. It shows up in the catalog under both the crankshaft/timing gear figure and the timing cover/oil pump/relief valve figure, which tells you it lives right where the oil circuit runs through that cover on the timing side of the engine.
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Parts like this are easy to overlook until you're chasing an oil leak or doing a rebuild and find the passage weeping past the threads. Since it's a plug rather than a gasketed cover, it's worth pulling and checking whenever the timing cover comes off, especially if there's any sign of seepage around that area.
Our catalog record ties this one to timing-cover and oil-pump work across the early '70s appearances we have on file, but it doesn't spell out which specific models it fits. Give us a call and we'll confirm fitment before you order.
We've never carried this one. Tell us what you're after and we'll go looking — you'll get a price and photos before you commit to anything.
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