ATK Marine DM27 Chevy 4.3L V6 Rebuilt Long Block Engine

Description

Exhaust riser water leakage and camshaft lobe wipeout ruin commercial fishing skiffs during peak runs. The ATK Marine DM27 Chevy 4.3L V6 Rebuilt Long Block Engine cures water reversion failures through a marine commercial long block repower. This 4.3L V6 build develops 190HP, requiring mechanics to verify mechanical fuel pump pushrod clearance on early block castings.

Constructed around an ASTM A48 Class 30 gray iron block, this ATK Marine engine core pairs with cast iron cylinder heads, brass freeze plugs, and a nodular iron crank. Cold starter draw pulls 150A at 12V. Dry engine mass measures 405 lbs inside 25in length, 24in width, 26in height dimensions with 4.5 quarts oil capacity.

Key Features of ATK DM27

Fleet operators buy ATK Marine DM27 Chevy 4.3L V6 Rebuilt Long Block Engine units to re-power working skiffs while retaining mechanical carburetion and fuel pump hardware. The specialized marine camshaft reduces intake valve overlap to prevent seawater mist ingestion through wet exhaust systems.

• Displacement spans 262ci across a 4.000in bore and 3.480in stroke crankshaft radius.
• Mechanical fuel pump mounting boss supports original marine mechanical fuel pumps.
• Marine camshaft profile reduces valve overlap to eliminate water reversion through exhaust risers.
• Heavy-gauge brass marine expansion plugs prevent premature coolant leakage into the bilge.
• DM27 commercial core line-honing ensures true main bearing bore alignment across the block.
• One-piece Viton rear main seal stops crankcase oil seepage onto flywheel damper plates.
• Tri-metal copper-lead bearings absorb abrasive micro-debris to prevent crankshaft journal scoring.

Test Stand Dynamometer Boundaries

Test cell runs record vital data on every DM27 long block engine before dispatch. The V6 engine produces 190HP at 4400 RPM and 260 ft-lbs torque at 2800 RPM. Hot oil gallery pressure holds 52 PSI at 195°F fluid temperature. Compression gauges show 170 PSI across all six cylinders within 3% variance. Crankshaft main journal runout checks at 0.0003in TIR. Dynamic exhaust gas temp peaks at 1240°F under dyno loading.

Integration Demands Maintenance Guidelines

Mechanical throttle lever operation needs 5 lbs pull resistance. This pre-Vortec marine V6 engine is NOT compatible with balance-shaft timing covers, eight-bolt Vortec intake manifolds, or automotive road vehicle sensor configurations.

• Flush break-in engine oil and replace the marine filter element after 25 water operating hours.
• Inspect mechanical fuel pump mounting arm and pushrod wear after the first 50 running hours.
• Check cylinder head bolt torque down to 65 ft-lbs following initial thermal normalization runs.

Powertrain Guarantee Manifest Inventory

Protected under the dependable ATK Marine assembly standard, this marine unit features a 2-Year limited commercial warranty. The sturdy transport crate contains the long block engine, marine oil pan, valve covers, timing cover, oil pump with screen, and signed quality inspection sheet.