Injector lash issue after head gasket

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IslandTD5

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HELP! Injector lash bottomed out even with adjuster screw all the way out on cylinder 5 after head gasket and injector seals job.

Issue Description:

• Main Concern: Injector lash on cylinder 5 is too tight, despite the adjustor screw being fully backed out.
• Symptoms:
o Engine cranks but does not fire.
o The fuel pump primes for a prolonged period, indicating it might not be building sufficient pressure.
o Cylinder 5 injector remains too tight even after replacing washers and reassembling.

Work Already Performed on the Engine:

Here’s a list of all the parts replaced and work that has been done:

1. Head Gasket Replacement:
o Replaced with new head gasket and ensured proper torque sequence and tightening of head bolts.
2. New Head Bolts:
o Replaced old head bolts with new ones during the head gasket replacement process.
3. New Head Dowels
o Replaced factory plastic dowels with steel,
4. Hylomar Sealant:
o Applied between the camshaft carrier and cylinder head to ensure a proper seal.
5. New Intake Manifold Gasket:
o Replaced intake manifold gasket as part of general maintenance and reassembly.
6. New Exhaust Manifold Bolts and Gasket:
o Replaced exhaust manifold bolts and gasket during engine reassembly.
7. New Injector Copper Washers and O-rings:
o Replaced all injector copper washers and O-rings to ensure proper sealing.
8. New Injector Clamp Bolts:
o Replaced injector clamp bolts to ensure injectors are seated correctly.
9. New Rocker Shaft Bolts:
o Replaced rocker shaft bolts to maintain proper valve clearance.
10. New Starter Motor:
o Replaced the starter motor to address starting issues, unrelated to injector problem but part of general maintenance.
11. New Oil Cooler:
• Replaced oil cooler as part of routine maintenance.
11. New Filters:
• Replaced air filter, fuel filter, and oil filter.
12. New Injector Harness:
• Replaced the injector harness to avoid potential electrical issues.
13. New Timing Tensioner Washer:
• Replaced timing tensioner washer during engine assembly.
14. New Sump Gasket:
• Replaced the sump gasket during engine reassembly to prevent leaks.
15. New Fuel Pressure Regulator Gasket:
• Replaced the fuel pressure regulator gasket as part of addressing potential fuel pressure issues.

Troubleshooting and Observations:

1. Injector Lash Issue:
o Injector on cylinder 5 exhibits excessive tightness, despite the adjustor screw being fully backed out.
o Injector lash remains unresolved, suggesting potential issues with the injector or injector seat.
2. Injector Removal & Washer Check:
o After removing the injectors, it was observed that the washer on cylinder 5 did not crush, which might indicate an improper seal or installation.
o Replaced the washers and reinstalled the injectors, but cylinder 5 injector remains tight.
3. Cranking and Fuel Pressure:
o Engine cranks but does not fire.
o Performed the purge cycle (ignition on, press gas pedal five times), but fuel pump continues to prime for an unusually long period, indicating it’s not building enough fuel pressure.
o Checked fuel lines and confirmed fuel is reaching the injectors.
4. Injector Power Test:
o Used the Nanocom to test each injector, confirming that each injector is receiving power.
o Audible click heard from each injector during testing, confirming electrical functionality.
5. Camshaft Alignment Check:
o Confirmed that the camshaft sprocket is correctly aligned based on the numbered markings corresponding with the highest point of the camshaft lobe for the associated cylinder.
6. Cylinder 5 Injector Adjustment:
o Despite adjusting the lash by bottoming out the injector and turning it out one full rotation (per shop manual), injector on cylinder 5 remains too tight.
7. Fuel System Observation:
o Despite the purge cycle being performed, fuel pressure seems inadequate to support proper injector function.
o Need to confirm if the issue lies in the fuel system (fuel pump, fuel pressure regulator, or fuel line blockages).
8. Injector Well Observation:
o During the purge cycle, observed that no fuel pooled out of the injector wells, suggesting that the O-rings on the injectors are sealing correctly and there is no fuel leakage in this area.

Anyone ran into this issue? I’m about to take the injectors out a 3rd time and replace the genuine Land Rover o ring with an after market one to see if that does anything
 
I reinstalled the injectors, each with an audible click upon reinstall so I know they’re all seated properly, however 5 still has no lash, even before I bolt down the rocker shaft. The injector spring itself might be slightly higher than the others and the stem is setting slightly higher. Did the injector somehow become the issue while out of the truck?
 
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