Rear oil pan leak

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mitch_f1
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Rear oil pan leak

Postby mitch_f1 » Sat Aug 04, 2012 10:13 pm

So what I thought was my RMS leaking again actually turned out to be (I think) the rear oil pan join.

Image

So, would I be good to just smear a small amount of RTV gasket on that area?

mr bender
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Re: Rear oil pan leak

Postby mr bender » Sat Aug 04, 2012 11:16 pm

it might work .

when i pulled my gearbox out to fix my RMS it turned out it was the sump (same leak as you have)

there are two rubber seals, one on the front and one on the rear ,
mine sump was missing both and was replaced with gasket goo. it leaked really bad.

i had to lift the motor up about 200mm to remove the sump , and replace the seals and goo it again.

project.r.racing
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Re: Rear oil pan leak

Postby project.r.racing » Sun Aug 05, 2012 9:03 am

like all gaskets. the oil pan gaskets will fail with age also.

Mr Morlock
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Re: Rear oil pan leak

Postby Mr Morlock » Sun Aug 05, 2012 10:59 am

I am guessing that the silicone sealant is not standard seal medium. I do not think you will fix an oil leak by adding silicone to a sealed surface. Bender is probably right on the money.

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bigdog
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Re: Rear oil pan leak

Postby bigdog » Sun Aug 05, 2012 1:24 pm

New gaskets plus Mazda spec sealant as per the manual, check that bolts are tourqued correctly.
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mitch_f1
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Re: Rear oil pan leak

Postby mitch_f1 » Sun Aug 05, 2012 1:29 pm

A lot of people on the internet say that it is very unlikely to be the oil pan gasket as the silicone seals it incredibly well. I'm fairly sure the engine hasn't been out, so it is likely the OEM sealant in there now (although it does look a bit messy...). I am so stumped as to what it could be!!!

mitch_f1
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Re: Rear oil pan leak

Postby mitch_f1 » Sun Aug 05, 2012 1:55 pm

Bender, how did you raise the engine 200mm to remove the sump??

mr bender
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Re: Rear oil pan leak

Postby mr bender » Sun Aug 05, 2012 2:35 pm

unbolted the engine mounts and lifted the engine up with a engine crane.

if you split the sump it would be best if you remove it completey to clean it up and reseal
it again because the sump has a splash plate which is inbetween the sump and block and they both need gasket goo.

this is a picture of mine when i pull the sump off (note all the gasket goo)
:Image
these are the gaskets (or in my case the goo) they are ment to be rubber seals
Image
Image

this is the splash plate which goes inbetween the sump and block (in the sump in the first picture)
Image

hope this helps

project.r.racing
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Re: Rear oil pan leak

Postby project.r.racing » Sun Aug 05, 2012 6:46 pm

mitch_f1 wrote:A lot of people on the internet say that it is very unlikely to be the oil pan gasket as the silicone seals it incredibly well. I'm fairly sure the engine hasn't been out, so it is likely the OEM sealant in there now (although it does look a bit messy...). I am so stumped as to what it could be!!!
If yours is the pan seals. It will be the third time I have seen this in the past year.

Doesn't seem to be a usage thing. 100K or 300K milage, but all have been 20 year old engines or older.


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