I've got a oil leak on my freshly rebuilt '98 Neon DOHC. Was cam seals and stripped valve cover bolt threads, so I repaired those. Now I'm still getting a steady leak only when running. Oil pressure switch is dry, whole back of the block is dry, but there's a huge flow pouring down the splash guard for the alternator. Thus, I suspect the leak to be up high somewhere. I checked cam seals, they're fine. No head gasket leak, valve cover is secure now.

If I'm not mistaken, DOHC engines require no spark plug tubes, not that there's even oil in the wells. Just some oil running into the timing case, and a ton pouring down the block directly underneath the P/S reservoir. I've run my fingers all over, can't find anything. Really don't want to take it to a garage but I'm exhausted from rebuilding the thing 3 times in a row (rookie mistakes). I couldn't even drive it around the block it's leaking so badly, a quart every 3 minutes or so.

Can anyone share ideas please? I've redone and double-checked cam seals, head gasket, valve cover gasket, and am suspecting that somehow it's the crankshaft seal, and timing belt is picking up the oil and dropping it out the top. I don't know, literally 30 hours worth spent under this car and nothing to show for it, I'll hear and inspect any idea you guys have.

 

Try adding a dye to the oil and trace it back.

 

Whoops, forgot to update this thread!

So I'll admit I had been wrong and the oil was leaking from between the head and block on the firewall passenger corner. Seeing as I had no money to do anything else with the vehicle, I was faced with junking it or letting it sit until I had money for repairs, which would be a long time. I began to crank harder on the cylinder head bolts, and just add oil when it ran itself low. Heating and cooling the engine re-warped the head and I know it sounds like a terrible idea but now the engine can get to 6k rpms without a drip! Granted, I only ever get to 3.8k when I'm driving, because I know this is not a traditional repair and I'm probably on pretty thin ice here. So my oil leak is all gone, from a quart every 5 minutes to sealed.

I did however experience some real issues getting my valve cover to seat properly. The bolts would bottom out, grommet to cylinder head, and there was so little pressure against the head that it was leaking too, enough to chunk the valve cover gasket. I ended up stacking 3 washers under each valve cover bolt, and that gave me the leverage needed to compress the gasket. Now I can't make it visibly move by pressing with my fingers. It sealed, no leak. Had to replace tube seals too, it took them out.