Hi guys,

My recently purchased 92 Civic with B15B4 carby engine has an oil leak from the rear of the engine I've been unable to pinpoint.

I've checked over the rocker and header gaskets and from what I can see there is no leakage in these spots. I've dropped the oil sump when doing an oil and filter change and all is in working order with the sump gasket looking fairly new with no cracks or damage. When I did drop the sump and pulled the filter, it seems the leak could be just above the oil filter itself, though it was very tucked away and unable to be seen with a torch.

After taking the car for a good drive two days in a row, I noticed mad leakage on the second run. After wiping the area down afterwards, the leak persists and seems to be worse during a drive rather than sitting at home.

Wanted to know if there are any spots in particular it could be coming from and if anyone has experienced a similar issue.

Thanks for your help!


Is there any area above the oil filter that oil could be coming from?

 

The oil pressure sending unit is directly above the oil filter. This sensor is what makes the dreaded "oil" dash light come on when it senses low oil pressure. If someone damaged the threads or overtightened the sensor, it could have cracked the block and be the source of the leak.

I'm not very familiar with the carbureted versions of the Honda D-series engines, but if it has a PCV system, there should be a "black box" to the right of the oil filter. This is an air/oil separation chamber. It fits to a large hole in the crank case with an o-ring. It could be that this o-ring is damaged, causing the leak.

There are other potential sources, but those are the two I would check out first.

 

Thanks very much Dax, I’ll check over this next.