Hyundai Repair: Hyundai G4CPS Motor, valve clearance, firing order

Question
Hi HT

We have recently overhaulded a Hyundai G4CPS Motor, checked the timing and all settings correct but 0 compression cylinders.  Could you suggest some reasons for this.

Answer

DOHC Sirius Engine In general, this is a purely mechanical issue.  Since this is a newly rebuilt engine, I'd recommend starting with a visual check with the valve cover off.  

Set the crankshaft to top dead center.  In this position, all cylinder #1 valves should be closed and all cylinder #4 valves should be slightly open (or vice versa).  Firing order is 1-3-4-2.  With each 180 degree turn of the crankshaft, the above valve statuses should move one cylinder along the firing order.  

Check to verify there is some valve clearance when the valve is completely closed.  It's possible the lifters may be pumped too far, holding the valves open.  If there's no clearance between the rocker and valve, it's likely this is occurring.  

If this is the engine I think it is (2.0 Mitsubishi DOHC), it's possible that the plate between the two crankshaft sprockets has been installed backward.  There should be a notch on the plate that will align with the pointer just as the marks on the sprockets.  If the notch doesn't align in the same position as the marks on the sprockets, expect that the plate has been installed backward.

I've attached a picture of what I expect this engine looks like.