IMS or RMS Leak '03 Boxster with 235k miles
 

For the past few years my '03 Boxster has been leaking oil from between the engine and transmission. Last year it lost about a quart over 6 months of driving. The car has 235k miles but is in good shape and drives well.

I decided to tackle the oil leak this week and suspected it was the RMS. I pulled out the transmission and removed the flywheel. The RMS has a newer 997 part number and looks like it might be leaking a little, but not a lot. Meanwhile the IMS is caked in oil.

I was not planning on addressing the IMS because I figured after 235k miles if it was going to fail it would have already failed.

Two questions I would love some help with

1. Does this look to you like a leaking IMS?

2. What would be the most cost effective way for me to fix this leak?

thank you!

http://986forum.com/forums/uploads02...1618880405.jpg

It looks like both the RMS and IMS seal are leaking. If you are certain that you don't want to replace the IMS bearing, you can just replace the flange seal. I recently did it on a high mile engine that I got with a parts car and it was easy to do.
Here's the seal at Pelican: https://www.pelicanparts.com/More_Info/99610511201OEM.htm?pn=996-105-112-01-OEM&bt=Y&fs=0&SVSVSI=1052

To replace it you should follow the IMS retrofit procedure up to the point of removing the flange. Do NOT try to just unbolt and remove the flange. I'd recommend following this: https://imsretrofit.com/wp-content/uploads/2017/10/IMSR-Pro-Manual-03-23.pdf
***You will need a tool to lock the cams and new cam plug.***

Another "while you are in there" thing to consider is removing the outer seal of the existing IMS bearing. That way you can inspect it and leaving the seal off lets engine oil lubricate it better (or so I've read). You can find discussion on that and decide if it's a good idea for you or not.
:cheers:

I agree with 78F350 on the IMS flange and bearing seal.
I would have expected to see more oil in there given the quantity that you report losing. Seepage could account for what you see. It would seem that the IMS is seeping more than the RMS but the RMS is not that difficult when you have it in front of you... and it is not very expensive

Decided to order the Pelican Parts IMS bearing kit. For $175 I'm not making a huge investment in an engine that could fail for other reasons in the near future. If I have to go to all the trouble of locking the cams + crank to replace the seal, may as well just pull the bearing out too.

I also bought a used set of the LN Engineering IMS tools that I plan on re-selling once I replace the bearing.

Great choice for your situation. The Pelican kit has the same bearing that your car came with originally and comes with an improved center bolt. Take your time and follow the correct procedure and it should be good for another 235k miles.
:cheers:

Just a side note, I`m not sure which Pelican kit you mean, but the one I remember is a single row bearing that is good for 40k according to Pelican and it`s nowhere near to the robustness of the original dual row. It`s a usable alternative but won`t last 235k probably. Or have they come up with another one?

EDIT: oh, looks like it`s actually a single row originally. Pretty impressive mileage! Yes, in that case there`s no reason to think why it would not last that long :)

In reply to Homeoboxter...
Honestly in most cases, I'd opt for an LN dual row or IMS solution. Years ago I put the Pelican Parts bearing in an '01, replacing what had been a good, but grease-less dual row bearing. I still wish I had gone with a better option while I was in there.

In this case, if the single row got it to 235k miles, I doubt that the equivalent replacement will be a problem. At that point, ~$850 just for a bearing wouldn't make sense to me unless it's part of a more extensive rebuild.

After locking the cams I would remove the chain tensioners as well to keep the IMS shaft from moving to the side..

Yes, I agree. (If that`s indeed the original single-row bearing at 235k that also corroborates the idea that the failures might be due to some sort of misalignment issues of the engine halves or not perfectly lined up bearing bores in the factory which add some minor stress to the bearing eventually leading to premature failure. But I don`t want to hijack the thread and start another IMS debate, hence the paragraph) :)

Maybe the RMS leaks and just accumulates around the IMS Bearing cap,.in any event you have gone this far so why not replace it..and 235 K that's Great !!

PS how long did it take to pull the engine ? Thanks Frank

Took me about 4 hours to drop the transmission, not including an additional 2 hours to drill out the rusted exhaust flange bolts that connect the headers and the cats.

Really wasn't bad at all. The Burner's Cars youtube videos were a big help, as was the 101 projects book.

That's Great info..Just 1 more question car lift or jack stands ? Thanks Frank

Just jack stands. I have a good set of four that go up to 21" high

https://www.amazon.com/gp/product/B0019JVIPM/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

+1 for a good set of 6 Ton or better jack stands. I used to use cheap ones. Never again when I'm going under the car.

Thanks for the Amazon link ,.Ive got 4 Gigantic ones..but my jack cant lift the Box that tall,.so I will be in the market once again !

You could try putting a small block of wood on your jack arm to extend the road. My Harbor Freight Daytona jack just barely lifted high enough for this job.

In good news I've made a lot of progress on this repair. New IMS bearing and RMS is installed! I also put on a replacement flywheel, pilot bearing, clutch and pressure plate. And I've prepped the transmission for reinstallation with a new slave cylinder, throwout bearing, clutch fork, clutch tube, and pivot pin. So many new parts!

When I took the IMS cover off the seal was brittle and falling apart. No wonder it was leaking! The cover is the newer style, so the IMS must have been serviced at some point in the past. The bearing I removed felt tight and did not need to be replaced but no harm buying that piece of mind. The bearing I removed is the same NSK model as in the new Pelican Parts kit, although manufactured in Poland vs. the new one made in Japan.

Looks cleaner than before too :)

http://986forum.com/forums/uploads02/ims31619840182.jpg

The car is mostly back together! I just need to reinstall the sway bar, chassis brace, belly pan, and engine cover.

I started it up today once I got the muffler back in. I notice a ticking noise coming from the engine. I don't think this noise is new but it sounds louder from sitting all winter. Could it be a loose spark plug?

https://photos.app.goo.gl/fzNbrNiF3FWrTZP89

sounds like cam tensioner pad/chain. A loose spark plug isn't going to cause any noise, just misfire/rough running.

Give it time to warm up also and check your oil level.

Yep, oil level was a little bit low! I topped off the oil and took the car for an extended drive and it sounds a lot better now. Still a slight clicking but basically the same as it has for the four years I've owned it. The engine feels smooth at idle and revs hard up to redline.

In other good news no more oil dripping from the IMS/RMS!

Yes a loose spark plug will make a noise.
Every time the piston comes up on the compression stroke it forces air past the spark plug threads. that is when you can hear it.
Sounds like an exhaust leak at the manifold sometimes like a click.
Does not always cause misfires.
Best thing to do is check all your plugs with a torque wrench;)
Easy Peasy.