this shits been buging me for 2 weeks now and i cant figure what it is. ive been trying to start this L16(1.6litre) datsun engine thats been sitting for 7+ years. the compression in cylinder 1 and 2 seems to be fine but 3 has some compression but not like 1 an 2 and 4 has no compression what so ever. i thought it was spark at first but it isnt all plugs work and the spark plugs are brand new. now i did manage to get it running but very rough and only on 2 maybe 3 cylinders at most. after running it for about 5 mins at most i took the new plugs back out. all where fine but 4 was still new(u know no black or anything NEW) it was a little wet. no oil or anything leaking inot any of the clyinders. running really really rich though. my conclusions where…
-now what i was thinking was could it be possible that a valvcould be stuck open?
-timing might be off?
-carb not working properly?
To the best of my knowledge (which isn’t much) the more common culprits of no compression are either a blown headgasket or severely effed rings, which is bad. But since you said there’s no oil in the cylinders would doubt the rings are your problem. **Edit: Now somebody correct me if I’m wrong, but all valves when they are totally open, do they not protrude past the highest point a piston will reach in it’s stroke? Thus ruling out a stuck open valve?
If you have no oil in the engine this might make for lower compression but there should still be some. I would try puting some oil into each of the cylinders and testing the compression again. If the spark plug looks new and the engine has been running you probably have no spark if it’s a points style distributor they ware out so you should check it. It could also be the spark plug wire.
