Rep Power: 0

I went after the rear main seal a few months ago and I was right because when I got to it, i watched it for a few days and it was leaking from around the seal, no doubt. So I got a new rear main from Honda and put it in with some lithium grease and tapped it in with a PVC coupler fitting and a small sledge, just lightly tapping to make sure the fit was uniform and good. I didnt feel like I hit it too hard and it seemed good to go. I did notice it was still losing oil. Not as much as before I replaced the seal, but still enough to notice. Maybe a quart every 700 miles. I went to change the oil today and there is oil leaking out of the inspection plate again indicating another breach at the rear main again. So I feel defeated and I really hate that I may have to break open the trans again. But now I'm not even certain that that's the issue. What else could it be? Has anyone else been here and encountered this sort of thing?

I'm super discouraged because I also replaced the clutch and a multitude of other parts to get the car ready for another 100k miles.

I'd appreciate any advice on what the problem could be.

 
Rep Power: 367

that's a painful one to redo...

 
Rep Power: 224

It's not coming from up higher and just leaking down is it? You'd be looking for a leak at the cam plug or maybe the VTEC solenoid. What about a leak from the oil pan? Just trying to avoid pulling the transmission...

 
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In addition to the VTEC, also check the plastic cam plug on the passenger side of the cylinder head. If that leaks, it spills onto the transmission, then leaks down into areas that often look like the rear main seal is leaking. We had this happen after doing similar work (rear main, clutch, input shaft bearing, etc). Elated to figure out the rubber seal on the cam plug had dried out and started leaking, instead of the new rear main.

If it ends up being the main, I have read that some crankshafts develop a groove from the original main seal. Sometimes a sleeve kit (speedi sleeve?) may be needed to resolve this issue. I believe it goes onto the crankshaft before installing the rear main and is meant to resolve this type of issue. Here is a video where the mechanic documented this problem on a 2001 Civic, fixing it with a sleeve.


Either way, good luck!

 
Rep Power: 0

This might actually be my problem with my 04EX 5speed. Would you happen to know the part number for the gasket that goes behind the plate that the seal sits in?

 
Rep Power: 224

The crankshaft seal in the oil pump is part number 91212-PLM-A01. The O-ring that is between the oil pump and block is 91308-P3R-T01. The rest of the oil pump uses Hondabond to seal to the block. Not sure which you are asking about.

 
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If I recall correctly, there was no gasket behind the rear main seal plate (that holds the rear main seal). It uses Hondabond or an equivalent grade RTV gasket sealant. Edit - do note that the EX may be different from the LXSE that we own...