So my 1st gen crv (1998, b20b4) recently started leaking more oil than it used to. The oil is all around the oil pan gasket and has started dripping onto the downpipe and smoking, I don't know where its leaking from, I checked the dip stick tube, its not there, I would think oil pan gasket but less than 3 years ago I replaced that with the FelPro gasket with the metal inside. It definitely could be the gasket but it seems odd for it to be leaking so badly already and its also oily a bit above the gasket. My other guesses are crank seal or rear main seal. Also, this plug bolt thing that is shown in the picture as well as the seal that is around it(I think its the oil pump housing? maybe the o ring that seals the oil flow into the block), I'm not sure that looks oily enough to be it but maybe. I just cleaned everything today and will look under the car again tomorrow after I drive it.

Any ideas of where it could be leaking from would be appreciated. Thanks.


To the left is the timing cover and to the top right is the alternator.

 

the crankshaft seal is most likely the cause. sometimes this will get oil on the timing belt and that can weaken it.

I would recommend you make plans to do a new timing belt and seals (crank and both cam seals) before any real damage is done.

oil pan fasteners like to loosen themselves on the B20. I like to use low strength thread locker on them which can help. but short of doing that, at least check they are still tight.

rear main seal could be leaking too if the front one is. this is usually from age and the front gets replaced as part of regular service so it's usually newer than the rear main. replacing it is a bigger job than the other stuff. unless you're doing this yourself, it's probably not worth the labor to have it done. just keep an eye on the oil level and park over some cardboard.

it's not impossible for the oil pump to block area to leak, but that usually only happens if some dope has taken it apart and not resealed properly. the factory sealant and the crush washer behind the discharge port plug ought to go the life of the engine without issue.

 

Oil pan bolts are fine I changed the gasket myself, they have been checked since also. While I'm in there I will be doing all the other stuff under the timing cover, if that is where the oil is coming from. Kicking myself for not doing the rear main seal when I changed the transmission, not the smartest move on my part.

The oil pump seals to the block with an O ring not a crush washer and the o ring leaking is a known issue, I'm leaning towards this being the source of the leak, I have not gotten back under the car yet though to clean it better and inspect.