Overview — Crankcase Air Breather 1117402690
1117402690 is the crankcase air breather (ventilation valve) fitted to the Isuzu 6HK1 diesel engine family used across Hitachi excavators. We can supply all the original and replacement part numbers listed below, in stock or available on order — welcome to enquire by part number.
Parts Characteristics
The breather returns blow-by gas from the crankcase into the inlet system while an internal metering passage separates oil mist, so the engine breathes cleanly without pumping oil into the intake. Construction is a compact moulded body with a threaded or barbed fitting, built to live on a hot engine bay and resist oil, heat and vibration. As an OEM-spec replacement it restores the designed crankcase pressure balance, which keeps seals and gaskets happy.
Applicable Models & Applications
Primary applications are Hitachi ZX300, ZX330-3 and ZX330/350/360-5A class excavators powered by the Isuzu 6HK1 engine, where the valve sits in the crankcase ventilation circuit. The same 1-11740-269-0 / 11174-02690 reference also appears on Isuzu FVR34 commercial chassis, so the valve suits any 6HK1-powered machine sharing that ventilation layout. Confirm your engine model and the original fitting before ordering.
Maintenance & Replacement
The breather is a service item rather than a lifetime part. Check the vent hose for kinks, cracks or oil saturation at every engine service, and make sure it is routed away from hot manifolds. If the valve shows heavy oil weep, carbon blocking, or the machine develops crankcase pressure symptoms (oil pushed past the dipstick or rear main seal), replace it and clean the hose. A blocked breather raises crankcase pressure and can push oil out of gaskets, so it is worth replacing proactively during major service. Fit the new valve with the hose clamp correctly seated and orient the outlet exactly as the original did.
Price Reference (USD)
The reference price for this Air Breather (1117402690) is approximately USD 8 – 35 per unit depending on grade (OEM vs aftermarket), quantity and shipping destination. This is a planning estimate only — confirm current pricing and availability with our sales team before ordering.
Also in the AIR Series
4206637, 4343365, 4351039, 4385011, 4387692, 4434017, 4642820, 4647751, 4652385, 4652387, 4653191, 4684045, 4695870, 4698585, 4698614, 4698821, 4698822, 4712599, 4714414, 643016, and more.
Racer Machinery is a dedicated construction-machinery parts supplier — we keep the full AIR breather series in stock and verify every number against your machine before dispatch. Send us your part number and machine model, and we will confirm fitment, price and lead time. Same-family breather part numbers are available on request.







