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second time IMS seal change ...and leaking again

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Old 03-27-2010, 10:02 PM
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mmasse
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Default second time IMS seal change ...and leaking again

I took the tranny out for a clutch job 2 months ago, and decided to change the RMS (it was leaking) and to check the condition of the IMS bearing. The IMS bearing was in good condition so I replaced the cover and seal. After a couple of week I started seeing some small leaks coming from the bottom of the engine. Fearing it could be the RMSI decided to drop the tranny again to check it. The RMS was not leaking but the IMS was. I chaned the seal of the IMS cover again...and now after a couple of weeks it is leaking again. WHAT COULD BE WRONG?? I notice that when I disassembled the IMS, even though I took the chain tensioners out, the IMS bearing was not sitting centered on the case. I had to force the IMS cover to fit into the hole. Might this be the problem?

thanks in advance for your help
Old 03-27-2010, 10:32 PM
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ivangene
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change the o-ring too? and the bolts? (bolts will leak)
Old 03-27-2010, 10:49 PM
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15psi
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There are upgraded Porsche parts - new wider seal, flange to hold seal and bolts.
Old 03-27-2010, 10:52 PM
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Macster
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Originally Posted by mmasse
I took the tranny out for a clutch job 2 months ago, and decided to change the RMS (it was leaking) and to check the condition of the IMS bearing. The IMS bearing was in good condition so I replaced the cover and seal. After a couple of week I started seeing some small leaks coming from the bottom of the engine. Fearing it could be the RMSI decided to drop the tranny again to check it. The RMS was not leaking but the IMS was. I chaned the seal of the IMS cover again...and now after a couple of weeks it is leaking again. WHAT COULD BE WRONG?? I notice that when I disassembled the IMS, even though I took the chain tensioners out, the IMS bearing was not sitting centered on the case. I had to force the IMS cover to fit into the hole. Might this be the problem?

thanks in advance for your help
What Ivangene said.

To add to it: Did the end plate have a single o-ring or a wider rubber seal with 3 ribs? If the former the end plate should be replaced with a newer updated one with the wider seal with the 3 ribs. Along with the new end plate should come 3 new bolts with their threads treated with some sealer (micro-encapsulated something or other).

Since the bolts thread into holes that are through into the crankcase oil from the crankcase can seep past the threads and around the heads of the bolts and mimic an IMS end plate seal leak. And a bad RMS can mimic a leaking IMS end plate seal leak too, just in case you didn't have enough to think about.

Did you fit the new RMS seal in so the new seal's lip was at the same place as the old seal's? If so this can be a leak source since the oil seal could have -- it is not uncommon -- worn a groove/depression around the crank journal. If the new seal installed right where the old one was the seal will leak. The technique is to install the new seal either a bit deeper -- if room -- or a bit shallower than the orignal seal installed to avoid this.

Even if the end plate the newer one the seal might be compromised and a new seal or perhaps a new end plate with a new seal necessary.

Of course new bolts are needed, properly treated, or at least thoroughly cleaned and re-treated with some proper thread sealer to prevent the oil from seeping past. The factory recommended repair steps might just specify new bolts. There's usually a good reason why fasteners are not reused and sometimes metal fatique ain't it. Sometimes it is the thread treatment that is not reliably duplicated outside of the bolt/fastener factory.

As for having to force the end plate... Not sure I like the sound of that. You certainly could have damaged the seal and caused the leak. If this is all that resulted from your installation of end plate to an out of position IMS consider yourself damn lucky.

One possible course of action would be to remove the tranmission, clean everything up and then remove the RMS and the IMS end plate, but before doing so taking whatever precautions are necessary to ensure the IMS remains in position and the camchains do not experience a change in timing.

Then carefully install a new RMS making sure to not install it where the inner seal lip runs where the old one ran.

Then install a new IMS cover plate, one that has the latest/greatest seal, and of course 3 bolts of with the proper treatment.

Sincerely,

Macster.
Old 03-28-2010, 07:07 AM
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mmasse
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Originally Posted by ivangene
change the o-ring too? and the bolts? (bolts will leak)
what o-ring? you mean the one that goes on the cover? if so, I did twice already. I also install new bolts both times. I the any seal or sealant need for the center nut?

thanks
Old 03-28-2010, 11:42 AM
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the o'ring

Last edited by ivangene; 11-07-2010 at 11:49 AM.
Old 03-28-2010, 11:56 AM
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Chris996
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WHAT COULD BE WRONG?? I notice that when I disassembled the IMS, even though I took the chain tensioners out, the IMS bearing was not sitting centered on the case. I had to force the IMS cover to fit into the hole. Might this be the problem?
There are two chain tensioners to be removed. This should center the IMS shaft.



Upgrade the IMS:

http://www.lnengineering.com/ims.html

Old 03-28-2010, 12:03 PM
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ivangene
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AWE - I know what "might" be wrong...if you remove the lower tensioner and the ims (sideways one) and still are not centered - MAYBE the upper tensioner is stuck (worn, and not working right) This would cause the IMS center to be towards the drivers side of the hole

what do you think???
Old 03-28-2010, 12:07 PM
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ivangene
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so the leak IMO is from the bolts not being re-sealed - did you do that last time?
Old 03-28-2010, 12:19 PM
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mmasse
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Originally Posted by ivangene
AWE - I know what "might" be wrong...if you remove the lower tensioner and the ims (sideways one) and still are not centered - MAYBE the upper tensioner is stuck (worn, and not working right) This would cause the IMS center to be towards the drivers side of the hole

what do you think???
ivangene,

I did replaced the bolt for encapsulated NEW ones. Now I have not replaced any o-ring on the center bearing bolt. Actually I did not notice there was an oring there &@#^!@.IMS not being centered, what you are saying is exactly what is happening. The IMS is is towards the driver side. Ho do I solve that?

Thanks a lot

Rgarding the
Old 03-28-2010, 12:28 PM
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ivangene
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its a total guess - but you might have to remover the upper tensioner (though normally that is not required) there could be somthing not right with it (or IIRC you had removed the IMS cover without removing the 2 tensioners the first time around - that might have casued the abnormallity)

are you sure that is your leak? it is possible that something else is leaking .....
Old 03-28-2010, 06:12 PM
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mmasse
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ivangene,

you are right that I did not remove the tensioner the first time around< what abnormality can this cause...and how do I solve it?

On the leak, I would assume it is the o-ring that I have not replaced. What do you think about that?

thanks
Old 03-28-2010, 06:42 PM
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Originally Posted by mmasse
. What do you think about that?

thanks
I think you are damn lucky that your cam time didnt jump and you ruin the engine when the vario cams kicked in.

If you didnt replace the "oh" ring. I would say that seems to be a common thing that wasnt changed all 3 times?

Kinda like getting divorced for the 4th time and wondering whats wrong. You gotta look at what the common componant is?
Old 03-28-2010, 07:21 PM
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ivangene
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double check which bearing you have IIRC only one style uses the o-ring... not sure but I think the other one has an internal oring on the housing?? someone has to confirm
Old 03-28-2010, 10:22 PM
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Doesn't Engine pinned at top dead center before flange removal help alieviate side loads on the IMS?


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