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Discussion Starter · #1 ·
Hello all!

A friend asked me to help with his ALH not starting. Long story short, a lifter went, damaged the head and piston. The block and head have all been replaced. It cranked over, no smoke, no start. Pulled the valve cover and found the cam 180 degrees out and the IP timing off. Removed the cam, reinstalled with #1 at TDC, everything seems to be timed correctly now. Used a mighty vac and primed the IP, then the injector lines, seems to be sufficient fuel pressure at the injectors, fuel jumps 12”-14” when the lines are cracked and you crank it over. Metered the glow plug harness, and glow plugs, all tested good. Rpm is indicated when you crank so I assume the crank position sensor is working.

We have some smoke out the exhaust now when we crank but no start, not even a sputter.

Any ideas for next steps? Re-check timing? Compression test?

Thanks all!
 

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Hello all!

A friend asked me to help with his ALH not starting. Long story short, a lifter went, damaged the head and piston. The block and head have all been replaced. It cranked over, no smoke, no start. Pulled the valve cover and found the cam 180 degrees out and the IP timing off. Removed the cam, reinstalled with #1 at TDC, everything seems to be timed correctly now. Used a mighty vac and primed the IP, then the injector lines, seems to be sufficient fuel pressure at the injectors, fuel jumps 12”-14” when the lines are cracked and you crank it over. Metered the glow plug harness, and glow plugs, all tested good. Rpm is indicated when you crank so I assume the crank position sensor is working.

We have some smoke out the exhaust now when we crank but no start, not even a sputter.

Any ideas for next steps? Re-check timing? Compression test?

Thanks all!
Compression Test

Have you primed the fuel system to get all air out ?


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As Super suggests, compression test.

The block was replaced, why? Rare that a block gets trashed. If that happened then I'd have little confidence in the rods and pistons: no mention that these were checked, in which case I'll comment on them below (please don't slam back at me for bringing it up if they'd been checked- you didn't mention it, so not my fault).

One should have measured deck height with pistons installed. This would tell you whether the rods are OK or not: bent rods, even a bit, result in lowered length and lower compression- too low of compression is trouble for compression ignition engines. Also, no idea whether the correct head gasket thickness was used: again, if using one that's too thick will reduce compression; one that's too thin will present potential problems as well. There's little room for error in these things.

I doubt that there could have been any rod damage via just cranking. When there's contact sufficient to smash a rod it'll be enough to also mash lifters. But the concern is still there given that there's no mention of the rods and pistons being verified to be within spec BEFORE the engine was reassembled.

I don't have any confidence that this job was done correctly if you managed to put it together 180 degrees out. That's a HUGE oversight.

If there's an EGR valve make sure the ASV valve isn't stuck closed.
 
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