Valve-Train and Crankcase Parts: Selecting Rocker Buttons, Breathers, Bushes, Followers and Camshafts

Sea Keepers has published a second approved engine-component group covering the valve train, crankcase ventilation and bearing surfaces that keep a diesel engine breathing and timed correctly. The group includes rocker-arm button SK-00009-AV, crankcase breather SK-00010-AV, bushes SK-00012-AV and SK-00014, connecting-rod bushing SK-00015, cam follower SK-00016, camshafts SK-00017 and SK-00018-AV, and camshaft bush SK-00019-AV.

Treat a valve train as a matched system

The camshaft, follower, rocker mechanism, valve stem and their bushes operate as one load path. Wear at one interface changes lift, timing and contact stress elsewhere. A maintenance team should record the failure symptom and inspect the mating parts before ordering a single replacement. Replacing a cam follower on a damaged cam lobe, or fitting a new camshaft into worn bushes, can damage the new component during the first hours of operation.

Rocker-arm button SK-00009-AV

SK-00009-AV is the approved rocker-arm button or insert under part number 258-8721. This contact piece transfers rocker motion to the valve stem and needs the correct geometry, material and surface condition. Check the rocker-arm part number, valve-stem contact pattern, lubrication path and any maker limit for pitting or concavity. A small mismatch at this point changes valve lash and concentrates load on the stem tip.

Crankcase breather SK-00010-AV

The crankcase breather SK-00010-AV, part number 3102665, manages blow-by gas and oil mist while preventing pressure from building in the crankcase. A blocked or incorrect breather can drive oil through seals, increase consumption and contaminate the machinery space. Confirm whether the application uses an open breather, a closed ventilation system or an oil separator, and include hoses, seals, filters and drain fittings that are required for a complete service.

General bushes SK-00012-AV and SK-00014

SK-00012-AV is recorded against 418772-02/FR-26001001100, while SK-00014 uses FR-26001001100. Similar references can indicate a supersession, an assembly relationship or two catalogue conventions for the same family; they should not be merged without the equipment manual or maker confirmation. Specify inside and outside diameters, installed interference, length, oil-hole position and material, and state whether the bush will be finish-bored after installation.

Connecting-rod bushing SK-00015

SK-00015 is the standard connecting-rod bushing under reference 185-5571 / A046X327 for specified Onan applications. This bush supports the piston pin and must maintain oil clearance under alternating combustion load. Confirm engine model, rod part number, pin diameter and whether the workshop has the correct tooling to press and finish the bush without distorting the connecting rod. The final bore and oil-hole alignment are installation controls, not merely supplier dimensions.

Cam follower SK-00016

The SE8M cam follower SK-00016 is a needle-bearing follower associated with specified Perkins 4000 Series engines. Verify the engine build list, follower type, roller condition and pin or bearing arrangement. When a follower has failed, inspect the cam lobe for scoring and profile loss, check the oil supply and look for debris in the lubrication system before installing the replacement.

Camshaft group SK-00017 and camshaft assembly SK-00018-AV

SK-00017 is the Caterpillar camshaft group 243-0551 and SK-00018-AV is camshaft assembly 242-0673. The words group and assembly matter because the supply scope may include different gears, plugs, bearings or timing components. Confirm the exact engine arrangement, serial-number prefix, rotation and timing marks, and ask the supplier to state what is included. During installation, follow the maker sequence for timing, end float, bearing lubrication and valve-lash adjustment.

Camshaft bush SK-00019-AV

The CH11228 camshaft bush SK-00019-AV supports the camshaft in compatible Perkins diesel engines. A correct bush can still fail if its oil drilling is misaligned or its finished bore is outside tolerance. Match the bush to the engine build, record journal measurements, inspect the housing and confirm whether line boring or reaming is required after pressing. Replace adjacent bushes as a controlled set when the manual or measured wear calls for it.

What to send with a valve-train enquiry

Provide engine maker, model, serial number, arrangement or build number, the part number taken from the correct manual revision, quantity and photographs of both the removed part and its mating surface. Add oil-analysis or failure notes where available. For camshaft work, include journal and lobe measurements and state whether the request is for a bare shaft, an assembly or a complete valve-train repair package.

Approved record versus final technical approval

The linked Sea Keepers pages are approved Product Master records with reviewed names, images and public specifications. They create a reliable starting point for quotation and traceability. Vessel-specific technical approval is completed against the equipment identity and operating evidence supplied by the buyer, because the same descriptive name can cover multiple incompatible engine arrangements.

For the business buyer

Confirm the intended vessel or facility, operating environment, quantity and required approval before requesting a quotation. Capacity, coverage and service interval should be matched to the risk rather than selected by headline price.

For technical experts

Verify the delivered model against the maker reference, rating, dimensions, materials, operating limits and certification scope. Record the serial or batch number and retain the manufacturer datasheet, declaration, test report and maintenance instructions in the vessel file.

Product comparison

Compare alternatives on certified performance, compatibility, installation requirements, inspection interval, spares availability and total life-cycle cost. A lower unit price is not a like-for-like comparison when approval documents or service support differ.