The order we never skip — which is why the wrong part does not reach your site.
01
Confirm
Nameplate, OEM number and working conditions — checked against your machine, confirmed in writing before you pay.
02
Verify
Photos and video of the actual part, packed and labelled, before it leaves. What you see is what ships.
03
Prevent
Send the hour-meter reading and we log the service interval — you get a message before the next one is due.
04
Dispatch
Nothing leaves Xi’an until you reply "ok". You approve, then we ship — not the other way round.
Confirm this part for my machine
Machine model and part number are what let us confirm fitment in writing. Message is optional.
Overview
Fitment Note: Confirmed by the removed insert number and the cylinder-head seat bore. 33 mm OD. The insert is pressed in and the seat face is cut to the valve angle afterwards.
Specifications
MOQ
12 pcs
Type
Valve Seat Insert
Engine
CAT 3066 / S6K / C6.4
Material
Cast Steel Alloy
Position
Cylinder head (valve seat)
Replaces
CAT 5I-8012
Shipping
Rail / Sea / Air
Warranty
12 Months
Lead Time
15-30 Days
Application
CAT 311-323 series
Outer Diameter
33 mm
Aftermarket valve seat insert (valve seat ring) 5I-8012A — a direct replacement for the Caterpillar 5I-8012 insert. It fits the Caterpillar 3066 / S6K / C6.4 diesel engine family (also 3064 / C4.2), commonly used on CAT 311B / 311C / 312 / 312B / 312C / 314C / 318C / 319C / 320 / 320B / 320C / 320D excavators. Outer diameter 33 mm, cast steel alloy.
The valve seat insert is pressed into the cylinder head and gives the valve its sealing face. When the seat wears or recedes, the valve no longer seals — typical signs are a misfire, loss of compression, valve clearance that keeps closing up and, in severe cases, a burnt valve. Seats are normally replaced and recut during a cylinder-head overhaul.
Supplied as a single insert (cast steel alloy). Confirm the removed insert number and the cylinder-head seat bore before ordering; the insert is chilled / pressed in and then the seat face is cut to the valve angle.
Valve not sealing / leaking, low compression, valve clearance that keeps closing up, a misfire on one cylinder; a recessed or burnt seat damages the valve.
Installation Tips
1. Remove the old seat insert; clean and check the head seat bore for size and runout.
2. Chill / cool the insert and press it in squarely; do not damage the seat face.
3. Cut the seat face to the correct valve angle and check concentricity with the guide.
4. Lap the valve to the new seat and re-set valve clearance to specification.
