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hosickjg · 07-24-2010, 06:41 PM

I agree with "JFP in PA" and have the experience with this engine to back that up. I JUST split a Boxster block with a bad IMS (center of bearing came out by hand). I decided to split the block to have it tanked so there was a guarentee of not getting metal in my bearings later. I took the IMS in to my local machine shop to have the old IMS bearing race taken out so I could replace it. When the machine shop tried to remove the bearing they found that the main IMS sproket had started to separate from the IM Shaft. When I got there I was able to break it off by hand. Imagine the disastrous effects of that if I had just replaced the bearing with an LN bearing and not dug any deeper! What happens is as the IM Shaft starts to spin out of its proper place that puts stress on the main sprocket. The main sprocket is spot welded on and not build the withstand side-to-side stresses. In a very short amount of time the side-to-side stresses weaken the spot welds and thats it! Game over. LN Engineering states at the bottom of there IMS page (http://www.lnengineering.com/ims.html) that if your bearing has got to the point of coming apart that you should sent it for the IMS Upgrade instead of an IMS retrofit. Now that I have seen the reasoning behind this I FULLY AGREE.
In short, if you have chunks of metal in your oil filter and your IMS bearing looks like the picture I have posted, DO NOT JUST REPLACE YOUR IMS BEARING!!

07-24-2010, 06:41 PM	#9
hosickjg Registered User Join Date: Jun 2010 Location: Peterborough Posts: 33	I agree with "JFP in PA" and have the experience with this engine to back that up. I JUST split a Boxster block with a bad IMS (center of bearing came out by hand). I decided to split the block to have it tanked so there was a guarentee of not getting metal in my bearings later. I took the IMS in to my local machine shop to have the old IMS bearing race taken out so I could replace it. When the machine shop tried to remove the bearing they found that the main IMS sproket had started to separate from the IM Shaft. When I got there I was able to break it off by hand. Imagine the disastrous effects of that if I had just replaced the bearing with an LN bearing and not dug any deeper! What happens is as the IM Shaft starts to spin out of its proper place that puts stress on the main sprocket. The main sprocket is spot welded on and not build the withstand side-to-side stresses. In a very short amount of time the side-to-side stresses weaken the spot welds and thats it! Game over. LN Engineering states at the bottom of there IMS page (http://www.lnengineering.com/ims.html) that if your bearing has got to the point of coming apart that you should sent it for the IMS Upgrade instead of an IMS retrofit. Now that I have seen the reasoning behind this I FULLY AGREE. In short, if you have chunks of metal in your oil filter and your IMS bearing looks like the picture I have posted, DO NOT JUST REPLACE YOUR IMS BEARING!!