I have problems with Daewoo Lemas

The engine was running, they rebuilt it and the head gasket blew... I replaced the head gasket and now it won't start at all. The timing is perfect, the spark plugs are firing, the injector is spraying the fuel, but there's no explosion. I've checked everything and it still won't start. I measured the compression: Cylinder 1 - 70, Cylinder 2 - 70, Cylinders 3 and 4 only measure 55 and 50.
Any help would be greatly appreciated.

Hi,
maybe I can help you here. If you have spark and good fuel injection, and the timing belt is in good condition, my question is whether the engine has hydraulic tappets, and if so, did you prime them before installing them? Let me know...

Hi, if you already checked the compression, do it again, but first add a little oil to the cylinder before checking the compression and test it again. If the compression rises from 70 to 150 or more, the problem is in the cylinders, and if the compression only increases by 30 or less, the problem is in the valves

Thanks my dear friend, I got it started.
The problem was very low compression in the cylinders. I injected a little oil into each cylinder, towed it, and it started.

The compression only reaches 75 in all cylinders, but it recovered a little and I started it anyway.
Thanks.