17H1131 Fuel injection pump diaphragm for Nuffield 3DL with a BMC 2.6 litre 3 cylinder engine or BMC 5.1 litre 6 cylinder engine.
If the engine is surging in your 3DL Nuffield Universal Three it could be because this fuel injector pump diaphragm is leaking and needs replacing or the adjusting screw is worn.
View item 46 in this detailed parts drawing of Nuffield fuel injection pump parts.
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