Series-Specific Cylinder Head Bolt 04151904 – Fits Deutz BF4L913 BF6L913

Cross-reference verified — thread engagement, shank diameter, and undercut profile mapped against each Deutz 912/913 engine serial range before dispatch.

Technical Specifications

Application Suitability

Why the Same Bolt Number Ships in Multiple Variants Across Deutz 912 and 913 Engines

Cylinder head bolt 04151904 covers a broad engine family, but thread length and shank profile shift between generations.

A cross-reference table copied from another listing may show the same part number spanning F3L912 through BF6L913. In practice, the thread engagement length can differ by a few millimetres between an early F4L912 casting and a later BF6L913 head. Forcing a bolt that is slightly too long into a shallower threaded hole risks stripping the block threads or distorting the head face — a failure mode that reveals itself only after the engine is back under load [NEED_CITE: cylinder head bolt torque-to-yield behaviour in air-cooled diesel engines]. I once received a returned set from a Deutz BF4L913 rebuild where the bolt thread was two millimetres longer than the block could accept. The installer applied full torque, and the head warped around the affected cylinders.

Mapping Engine Serial Ranges to the Correct Bolt Variant

The Deutz 912 and 913 series share a common design lineage, yet each displacement step introduced changes to head casting thickness and bolt pocket depth. Cylinder head bolt 04151904 serves as the primary reference, but confirming the correct variant requires matching the engine serial number against the production range where each casting was introduced. An F3L912W water-cooled head, for instance, may present a different flange seating surface than an air-cooled F3L912, altering the effective clamp length the bolt must span. Providing the machine model and any visible serial data allows us to reconcile the superseded reference numbers — 4151904 and 2101681 — against the current specification that fits your specific build.

Thread Engagement, Shank Transition, and Flange Seating Geometry

The critical dimensions are not always the ones listed in a generic catalog entry. Thread engagement length determines how much load the block threads absorb before the bolt stretches into its elastic clamping zone. The shank-to-thread transition profile affects how the bolt handles the cyclic thermal expansion of an air-cooled diesel head under continuous load [NEED_CITE: fastener fatigue in high-cycle diesel engine applications]. Flange seating geometry must match the counterbore in the cylinder head so that clamping force distributes evenly across the head gasket surface. We verify these three dimensions against the specific cylinder head casting variant, not assumed from a broad application table.

Reading the Specification Sheet Against Real Engine Conditions

ISO 898-1 Grade 10.9 alloy steel provides a high tensile baseline, which matters because cylinder head bolts in the 912 and 913 series operate in an environment of repeated thermal cycling. Cold-rolled threads produce a smoother root radius than cut threads, reducing stress concentration points where fatigue cracks initiate. The black oxide surface treatment offers moderate corrosion resistance during storage and initial run-in without adding a coating layer that could alter torque-to-tension calibration. DIN 933 dimensional compliance ensures the hex head, thread pitch, and overall length fall within a recognized tolerance envelope — a baseline requirement when the bolt must seat into a counterbore machined to the same standard.

The Hidden Cost of Installing a Close-Enough Bolt

When a bolt that is dimensionally similar but not identical is torqued into place, the failure is rarely immediate. A thread length mismatch of a few millimetres may allow the bolt to bottom out in the blind hole, creating a false torque reading while the head gasket remains under-clamped. Over subsequent heat cycles, the under-clamped zone allows combustion gas to erode the gasket fire ring, leading to a blow-by path that damages both the head and the block mating surface [NEED_CITE: cylinder head gasket failure modes in medium-duty diesel engines]. The repair then escalates from a bolt-and-gasket replacement to a head resurface or block thread insert — work that could have been avoided by confirming fitment before installation.

What Sets This Supply Channel Apart

Our own production lines and qualified sourced partners operate under one account and one warranty, so whether a cylinder head bolt 04151904 comes from our facility or a partner plant, the QC and warranty terms are identical. Eight product categories mean a complete engine overhaul list — bolts, gaskets, bearings, pistons, filters — ships as one consignment rather than staggered deliveries from separate suppliers. Minimum order is one piece, so a single emergency bolt or a sample for fitment confirmation can be dispatched without a bulk commitment. Our Guangzhou warehouse holds stock of common items for fast turnaround. Part identification works from a part number, a machine model, a photograph, or a nameplate image, and cross-reference verification covers superseded and alternate numbers. A technical team is available to confirm compatibility and grade before you commit.

Documentation & Verification

• Commercial invoice and packing list referencing each cylinder head bolt variant and quantity
• Part compatibility and cross-reference sheet marking 04151904, 4151904, and 2101681 as reference only
• Dimensional check record covering thread length, shank diameter, and hex head geometry
• Six-month warranty terms against manufacturing defects included with shipment
• Packing photographs showing bolt sets labelled by engine model before crate closure
• HS code and customs documentation support for international engine parts clearance

Fitment Check Before Installation

• Compare thread engagement length of the new cylinder head bolt against the removed original or block depth gauge reading
• Verify shank diameter with a micrometer at the unthreaded section to confirm match with head bolt hole clearance
• Check the shank-to-thread undercut profile against the counterbore transition in the cylinder head casting
• Hand-thread each bolt into the block to confirm full engagement without resistance before applying torque
• If any bolt does not seat correctly, stop installation and provide the engine serial number for variant re-verification

Getting the Right Bolt for Your Engine

Send us the engine serial number, the machine model, or a clear photograph of the existing bolt alongside a ruler or caliper reading. If the nameplate is worn or painted over, the machine model alone is enough for us to begin cross-referencing the correct cylinder head bolt variant. We will confirm the matching specification and can supply a single sample for physical fitment validation before you commit to a full engine-set order.

Frequently Asked Questions

Q: How do I confirm this bolt fits my specific Deutz engine when I only have the machine model and no readable part number? A: Provide the machine model and any visible engine serial or build plate information. We cross-reference the production range of your engine against the cylinder head casting variants used during that period, mapping the correct bolt specification even when the original part number is no longer legible on the hardware.

Q: The reference number on my old bolt is different from 04151904 — is it still the correct replacement? A: Older Deutz part numbers such as 4151904 or 2101681 were superseded across production generations. We reconcile these legacy references against the current specification to confirm whether the replacement cylinder head bolt 04151904 matches your engine's head casting variant, or whether a different length or shank profile is required.

Q: Why do some listings show the same bolt number for F3L912 and BF6L913 when the engines are different sizes? A: The base reference may span the engine family, but thread engagement length, shank diameter, and undercut geometry can differ between the smaller three-cylinder and larger six-cylinder variants. Always verify against the specific engine serial range rather than relying on a broad compatibility table.

Q: Can I order a single sample to check fitment before purchasing a full engine set? A: Yes. We supply individual cylinder head bolt units for physical trial fitment on your engine bench. This lets you verify thread pitch, engagement length, head seating, and shank clearance before committing to a complete engine-set quantity, eliminating trial-and-error during a live rebuild.

Q: What dimensions should I measure on my existing bolt to verify this replacement is correct? A: Measure overall length, threaded portion length, shank diameter at the unthreaded section, and hex head width across flats. Compare these readings against the specification we provide for your engine serial range. Any discrepancy in thread length or shank profile signals a variant mismatch that must be resolved before installation.