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2005 EX-L Engine Oil Leak

53K views 27 replies 13 participants last post by  cnn 
#1 ·
I have a '05 ex-l, with 145,000 miles on it with no prior issues,that out of the blue started leaking engine oil from what looks to be the engine rear main seal. I removed the inspection cover and cleaned the area in question. But it looks as if the oil is coming from higher up. I'm trying to find a site that would show the break down of the rear of the engine. I would like to make sure before i start pulling the tranny out. It looks pretty tough. Thanks for any help or insight into this dilema.:)
 
#2 ·
Here is a diagram of the engine block. Part #23 is the rear main seal.

Honda Automotive Parts

I don't have access to the 2005 Service Manual but that would sure help you.
 
#3 · (Edited)
Have you recently switched engine oils (i.e. to synthetic)?

Wipe the oil off and monitor to see if comes back. Some possibilities other than a leaking rear main seal are a leak from higher above dribbling down to where you now see it and one member has mentioned that residual oil from an oil change can splash on a cross member and again dribble to where it is now.

Is it possible too that the oil is ATF that is dirty and looks like engine oil?
 
#4 ·
In most cars/vans, the RMS starts leaking anywhere between 90-150K or so.

You are doing the right thing: clean the area and monitor it.
Unfortunately, replacing the RMS in any vehicles is always a PITA b/c the transmission has to be removed to replace the RMS.
 
#5 ·
Is the oil loss noticeable ? A few oil drops a day or much worse ?
If it's just seeping a little (versus leaking), maybe you can just live with a it.
 
#6 ·
Thanks guys for all the info. The leak is definitly coming from the back of the block. And it is not trans fluid. Found tsb 141551 & 141508 that mentions something about oil leaking from rear plugs in the block, but i am not able to veiw the whole bulletins. Found these on a web site called AutoMD. I would still like to gather some more info before i pull the tranny out that way i know what i'm dealing with. Gotta do this over the weekend. Once again thanks everyone for the insights.
 
#7 · (Edited)
Did you check the PCV valve to make sure is not clogged or not working properly. I've heard that if it gets clogged, pressure forces the oil out the path of least resistance and out the rear main.

Just my .02

Pat
 
#10 ·
Finally got everything back together 10 hours later! Replaced rear main seal, also found that there is an o'ring behind the rms housing that also needs to be replaced when changing the seal. I believe that is what was leaking originally. Took pics of everything will post when i get a chance.
 
#13 ·
How much did they charge, if you dont mind. I just had my rear replaced on my 03 Acura TL at dealer for $400. Although I have spent a bit of money by servicing it there.
 
#18 ·
Hello I also have an '05 Odyssey and just started leaking oil near the rms at 99,000. Someone asked earlier if you just swapped to synthetic oil. I actually just did that last oil change and started leaking shortly after. I was just wandering how that could have anything to do with it? Also how hard was removing transmission? I'm not a mechanic but am very handy and have pulled my own motors in the past.
 
#19 · (Edited)
I realize this is an old thread, but to keep things organized makes sense to post here.

I have 06 EXL and all of a sudden, my rear main has apparently started leaking quite a bit. It drips on the undercarriage and gets on the hot exhaust and smokes. I have gotten under it and am sort of semi-pro mechanic so yes I know what I am looking for and engine was clean prior.

Looking for info, did this seal replacement solve issue? One would assume it would have, but I read on the technical forum (non gen specific) of guys having to have dealer replace this more than once for this problem, which would seem to point to something else. I am also going to test the PCV valve to make sure it works properly.

FYI - I purchased van with 55k and swapped in Mobil 1 5-20w and have used that. Van started leaking about 97k. I have purchased other used vehicles and swapped to Mobil 1 and never had a oil leak problem.

Melton46 - Looks like you do great work and have the equipment. Looks like you have to use an engine hoist to support the engine when you remove the cradle and tranny?
 
#20 · (Edited)
My car had the same oil leak that you have mentioned and yes it was the rear main seal leak. My car developed this leak at 125K miles on it.

IMO it wasn't you switching over to a synthetic engine oil that caused this leak.. we just got an engine that had an inferior rear main seal/O-ring. Actually from what I understand it is an O-ring that is leaking oil.

I had a shop perform the work and I provided the parts.


Any way here is a list what I replaced since the tranny was also out...

-Rear main seal and O-Ring.
-Axel seals left and right side.
-Left and right side sway bar links, since they broke during removal.
-replace the built in transmission filter
-Case of DW-1 ATF
-Tourqe converter seal
-replace the front sway-bar mount


Good Luck!
 
#21 ·
My '05 Touring has developed the RMS leak at just under 300k kms and have confirmed this with an independant Honda mechanic. So, after searching the forum for some info and perusing the Bernardi website for parts, I've been thinking of ordering the parts ahead of time so I have what's needed to get the job done. I've been quoted $1100 plus $109 for an alignment (this is Canada we're talking about) and even though the price is steep, I think I'll just have to bite the bullet and go ahead. I'd much rather have this shop do the job rather than go through the local dealership. The dealer just doesn't seem as honest or thorough imo.

So, as for parts required here I noticed that you have the option of ordering just the rear main seal and cover o-ring or what appears to be the entire rear main cover with the seal and o-ring already on there - just a bolt-off/bolt-on arrangement. Has anyone else come across this option and considered it? I'm also wondering if there's any gaskets needed for re-assembly including the tranny/bell housing.

Final question: should I bother with this or should I just let the shop handle it and pay the extra cost they charge for parts? I can easily save around 40 percent by ordering from the states.

Thanks
 
#22 ·
Anytime you replace the RMS, the trans needs to be removed, so you should also replace:
- Trans input seal
- Trans output seals x2.

Use only Honda parts, ask the shop to use only Honda parts.

The last time the RMS was replaced in my 1998 Volvo V70, the shop charged me 10h x $70/h = $700, but that was from 2008.
 
#23 ·
Hey guys.. I have developed a light RMS leak also and I am trying to understand how the oil is getting in the area behind the RMS cover(photos posted by Melton46)...

#1 - What is the purpose of the hole that the o-ring on the top of the RMS cover is sealing?
#2 - What is the purpose of the hole on the block on the left side about 3/4 way up
#3 - How is motor oil getting in behind the RMS cover and I assume their are some drain ports on the botton of the cover where it meets the oil pan/block?
#4 - Do we assume the oil varnish staining on the cover and the block is from hot oil fumes rising?

I looked over and through my Shop manual to try to find some answers to my questions, but I can not find anything...


Auto part Engine Aerospace engineering Machine Automotive engine part
 
#24 ·
The rear motor seal on my 05 leaked at around 110K. It's a cheap part, but labor is over 1K. One temporary solution is to use 5w-30 high mileage oil. The thicker oil will slow down the leak. The leak disappeared for a year. I had traded the van in for a new one before the leak started up again.
 
#27 ·
CB900F2,

I just looked at Factory Manual, some of the steps mentioned above by melton46 is unnecessary...

This is what Honda says...

1. Remove Axles/Transmission etc.
BTW, make sure you also replace the Trans seals x3.

2. No need to remove the plate at the rear end of the engine.
- Remove RMS (trick: use sheet metal screws to extract the seal).
- Whatever you do, do NOT damage sealing surfaces!!!
- Use appropriate driver (PVC coupler or socket etc.) to drive in new seal.

As to your questions re hole, O-ring on the rear of engine...I think the hole is there so some oil can get there to wet the RMS.
As much as seals are designed to stop liquid leak, the seals also need some oil to keep them moist and flexible.
Just my guess.


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