IMS at home... after it kills your family you are left with this!

[aneal000]

Hi All, I'm elbow deep in my biggest project to date. I bought a 2001 Boxster S with intermix. I've already pulled the engine and replaced the cracked head, along with all the goodies one might do when the engine is out and dissembled to this level. The last two things on my list before putting it back in was to do the RMS and IMS. Which brings me to this post... I bought the $185 single row "upgrade kit" from Pelican Parts. Went through the procedure to replace and reinstall but noticed the intermediate shaft was not centered in the opening, it was being "pulled" (so it seemed) toward cylinder 1-3. I had the chain tensioners: main and 1-3 removed. I also had the set screws that come with the kit in place but it still seemed like the shaft moved to the right (as you are looking at the IMS opening). This didn't seem to be a big issue until I went to put the cover back on. I was able to get the cover started and "massage" the shaft into the cover and got everything back together but just wanted clarification on this - if anyone knows. I suspect it is because of the orientation of the motor when I removed it - I'm thinking the valves were pushing the cams/chain to cause these to pull it this way. It had a lot of pressure on it the whole time. I know there has been comments and concerns about the timing chain slipping, but at least in this case I can't see how this would even be possible as the shaft does not just move around.

Just looking for thoughts on this before I put it back in... I don't think there are any issues, but looking for insight. Thanks!

On a side note, it had the dual row and looked/felt perfect (92k miles) and the oil behind the bearing was brown, not intermixed oil.

[Gilles]

Aneal,

Since you already assembled everything, all you can do is to rotate the engine several times and check that both cams align when you reach TDC, remember that you check the bank 1-3 to ensure the proper alignment, then rotate again to check the cam on the 4-6 banks.

Good luck!

[Meir]

did you set the engine to Tdc befor you started?

[aneal000]

I did not... (this is what I get for reading instructions on my phone) - went back and found my answer...

Taken from Pelican Parts IMS site:

[March 2015 Update]

Since this article was originally published in 2010, there have been some useful updates to the IMS Bearing Removal and Installation Kit that facilitate an easier and safer installation of the bearing. When I originally wrote this article, the only method available to lock the camshafts was to use the original Porsche factory tools, which costs several hundred dollars at the time. Since then, the camshaft locking tools have been added to the bearing extractor / installation kit. The use of these tools reduces the need for the "set screw method". To use the tools and lock the camshafts, begin by simply setting the engine to Top Dead Center (Figure 132). Then remove the camshaft end covers on both sides (Figure 133). Install the camshaft locking tools (factory tool is shown in Figure 137, the aftermarket tool varies slightly in appearance). With the engine crankshaft locked at TDC, and the camshafts locked with respect to the crankshaft, this should reduce the chance of disturbing the engine timing almost down to zero. NOTE: the IMS shaft will still tend to move off-center when you remove the bearing cover due to the pull of the chains/tensioners, so if you can install one or more of the set screws to hold it in place, it would still be a wise idea.

[Gelbster]

"I bought the $185 single row "upgrade kit" from Pelican Parts"
You are not the first ,nor the last(?) victim of the problematic Pelican instructions.
You do have a choice with the IMSB and replacing a dual row with a single row may be unwise.
Before you go much further it may be prudent to ask for opinions on the dual to single row replacement. A better alternative would be(?) the RND roller.
Or a generic dual row bearing with the original parts you already have??

http://lnengineering.com/products/ims/single-row-rnd-roller-bearing-ims-retrofit-kit.html

[aneal000]

I appreciate the feedback, but the new single row upgrade is already installed. Maybe at the recommended 40k service interval it will get "upgraded" again...

I had read quite a bit about changing out the IMSB (even if it is in good shape) when you have an intermix issues as the thin viscosity of the intermixed oil can cause the IMSB to fail early. Just surprised that the dual row looked/felt great and didn't have any intermixed oil behind it. I feel like I'm doing the engine a dis-service by taking out a stout looking bearing and replacing it with something half the size.