I'm not sure if I'm 100% correct. But my friend has a SOHC ZC swap in his DX hatch. He told me that when he took out his spark pluds he saw oil on them. This means that the piston rings are fried right? Like I said I'm not so sure on this and need some help figurin out what it could be.

 

most times its the valve cover o-rings..just get a valve cover gasket set/w the o-rings and replace them and see what happens ..

 

oil on the top of the plug? or the bottom of the plug ?

 

i'm having the same prob now and as Mr.Speaker said it could be the o-rings! changed mines and i'm still getting oil on the plugs....

 

if its oil on the threads of the plugs (not inside the tubes) then its something different... possible rings or valves. A compression and leakdown test will tell you more.

 

Aight kew, thanks for the info. I never thought that it woulda been the O-rings.

 

Valve seals, had the same problem on my old motor, toast.

 

On the side note, my friend asked my what the redline is for the car. Since Iono much about sohc engines, what is the redline for the sohc ZC?

 

Same as the dohc zc and almost very other D series made, 6800 if cut off on powa and cold rev limit, when it warms up it can go too 7200rpm, but if you shift at that then it will fall back on about 6800 i would imagine, this is with stock pm6 ecu though.

 

oil on the bottom of the spark plug could be the rocker arm assembly gasket. its probably in the hole but when you take out the plug the oil drips down to the threads.. i orderd some oring online and im goign to replace them hopefully this works if not then mine is something worse and i;ll get a different engine.

 

I replaced my o-rings and valve cover gasket when I had oil on the plug tops, and about 12 months later I was changing my plugs and found no oil in the tubes, but just on the threads...the wierd thing is, it was very clean oil, not burned looking, and it was on the threads, not the tips.

I'd like to know if it was just the rocker arm assembly gasket... sounds like an eaiser thing to deal with than new seals.

 

well it sounds just like my problem. so i hope its just the rocker arm gasket too. if the oil is in the tube and your not burning alot of oil then its got to be the rocker arm gasket.

 

Its called deal with it until you can save you're money and replace that shitty d series with a b series.

 

don't let that fool you. it could be the o-rings but it also could be from running rich, especially after a motor swap, putting on adjustable cams or an aftermarket ecu. but check the timing to see if you are running rich.