Two exhaust valves for Onan P-series and OL-series engines. Replaces Onan part number 110-3480. Two valves is one complete engine - one per cylinder. Head diameter is 1.100 inch and the stem is 0.275 inch, which makes this the smaller of the two valves in the head. The matching intake valve is 110-3479 and is ordered separately. Fits P216, P218 and P220; OL16, OL18 and OL20; and the LX720, LX770 and LX790 generators. All three P-series engines run the same 3.250 inch bore and the same cylinder head, so they share valves. The difference between a P216 and a P218 is stroke, not bore. The B-series is where people go wrong. B43 and B48 use exhaust valve 110-1955 and intake 110-2368, and the B-series exhaust stem measures around 0.341 inch against 0.278 inch here. They are not interchangeable and they are not close. While the head is off, look hard at the valve seats. These engines have a reputation for seat trouble, and Onan's own service manual calls for the seat insert to be replaced when it is loose in the head, cracked or severely pitted. A new valve dropped onto a failed seat will not seal and will not last. That is a machine shop job and it is better to find it now than after reassembly. Valve clearance, checked cold: intake .005 inch, exhaust .013 inch. Valve face angle is 44 degrees and seat angle is 45 degrees. Intake valves, valve guides, springs, keepers, seals and head gaskets are not included.
- TWO EXHAUST VALVES - ONE COMPLETE ENGINE - Replaces Onan part number 110-3480. Head diameter 1.100 inch, stem 0.275 inch - the smaller of the two valves in the head. The intake is 110-3479 and is a separate part.
- FITS THE P SERIES AND THE OL SERIES - P216, P218 and P220, the OL16, OL18 and OL20, and the LX720, LX770 and LX790 generators. All three P-series engines share a 3.250 inch bore and the same cylinder head, so they take the same valves. What differs between them is stroke, not bore.
- THE B SERIES IS A DIFFERENT VALVE - B43 and B48 take exhaust valve 110-1955 and intake 110-2368. Their exhaust stem measures around 0.341 inch against 0.278 inch on the P series. Not a variation on the same part - a different part. If you have a B43 or B48, this is not it.
- CHECK THE SEATS WHILE THE HEAD IS OFF - These engines are known for valve seat trouble. Look for seats that are loose in the head, cracked or badly pitted, because a new valve into a failed seat buys you nothing. The service manual calls for replacement when a seat is loose, cracked or severely pitted, and that is a machine shop job.
- SET THE LASH COLD - Intake .005 inch, exhaust .013 inch, both checked cold. Valve face angle 44 degrees, seat angle 45 degrees. Intake valves, guides, springs, keepers, seals and head gaskets are not included.