Wow, there has been a lot of debate about the new TuneRS Direct Oil Feed (DOF) system for the IMS bearing over on the Pelican Parts and 986forum boards. Details on the product are here:

http://tunersmotorsports.com/?page_id=103

I'm not going to add to the debate in this thread, instead I'm going to show the install on one of my personal vehicles, discuss my impressions of the system, and share some insight into how to make the install easier.

I plan to install a kit on my Gemballa 2000 Boxster S as funds permit, but for now I installed a TuneRS DOF kit on my TechArt 2003 Carrera 4S instead. This car is nice: turbo brakes, turbo AWD, full leather, carbon fiber interior bits, Fabspeed exhaust bypass, TechArt body kit, TechArt coilovers, stereo system, etc. When doing a risk versus cost analysis on this car I felt it is certainly worth $800 to make sure I have no engine issues with the IMS bearing. I plan to keep this car for a couple decades, so this is an investment in peace of mind for me.

Here is the car as it sat, just before I dropped the transmission. I bought this car some years ago from another 6speedonline member.

 

First of all I dropped the transmission, which is probably more tricky on the 911 than the Boxster/Cayman due to access in the middle of the car. I think it will be quicker on my Boxster because I can drop the rear bumper and exhaust pretty quick and get much, much easier access to the transmission. Complicating things on my car was the fact that it is AWD and I had to deal with the drive shaft going to the front wheels. Honestly, with all of the work involved in installing the DOF system the most time consuming was just removing the transmission to begin with! My car has 55K miles on it and the clutch was pretty worn, so I am replacing the clutch while I am in there.

This is one thing I like about the DOF flange. Look at the hole that the oil squirts out of. It's relatively small. I dont' think you need tons and tons of oil for this one bearing, just a reliable, consistent source. I think this small stream of oil will be perfect.



Getting the trans, clutch, and flywheel out, this is what I found.



The rear main seal was weeping a little bit of oil



But it looks like the IMS flange is leaking a lot more oil. My car had a flange with updated seal, but obviously it did not hold up over the last ten years.





The new DOF flange with updated seal will help with this problem, but I'll also install a new, updated RMS seal as well, bought from Pelican Parts (along with flywheel bolts, clutch bolts, and the new Spec clutch).

 

Now I have to say that the TuneRS instructions are AMAZING!!! Both LN Engineering with their IMS Retrofit and TuneRS with their DOF say that you should have them professionally installed. But the TuneRS kit definitely seems more suited for the do-it-yourself home mechanic as it is really complete (they even include red thread locker) and their instructions are 65 pages full of detailed photos. Let that sink if for a second... The LN Engineering IMS Retrofit comes with one page of instructions, no photos. The TuneRS kit has 65 PAGES!!! Plus there is a You Tube install video. You can't go wrong...

A couple of points to help others though - they talk about finding TDC on the crank. Here's a picture showing the notch lined up at TDC.



Also, when removing the cam plugs, there is a hole in the middle. It's easiest to just puncture that hole (you're going to replace them any way) with a pick and pry them out... easy!



Another suggestion, when installing the bearing onto the center shaft, use a square, calipers, whatever you've got, to check and make sure it is seated perfectly square. Here is what I used to check all of the way around the bearing to make sure it was seated perfectly.



Here is the bearing I'm using - a SKF 6204 2RSH JEM bearing. Don't use an old production bearing. SKF updated their seals, so make sure it says RSH, which is the new seal that can withstand higher pressures. 2RSH means there are two seals, obviously I removed the one that will get the oil spray. JEM means that it is a C3 tolerance bearing. You want C3 as stock OEM was C3. All this means is that the tolerances of the bearing are set to account for thermal expansion. This bearing will get hot, so you need to have tolerances for thermal expansion.

 

One thing to note, the TuneRS bearing shaft still has the o-ring in the shaft like stock, but the threaded portion is a much larger diameter to make the shaft much stronger than stock. They also use a two o-ring system to seal the shaft against the DOF cover.

When installing the snap ring on the bearing I placed a nut and bolt on the end of the bearing flange just to help make sure the snap ring didn't go flying off into the engine.



Now TuneRS says to grind out the place where the oil hose will connect to the DOF flange. You can go to your local hardware store, like I did, and pick up some of these $6 rotary files to make this job easy.



I ended up going an even easier route though. I took the bearing flange off, installed some set screws to help guide the DOF flange, and I test fitted the DOF flange and marked off precisely where I would need a hole. I then just drilled out the hole working up progressively from small drill bits up to 5/8" final. It only took me then about 30 minutes to test fit, mark, and drill the hole for the oil line.

 

DONE!!! This wasn't meant to be a detail by detail description of the install. That's all covered in those 65 pages of instructions! But I've highlighted some of the important parts of the install. I got the DOF flange on and the oil line run to the oil pickup point. It's tight to get in there, but I got it. It was easier for me to thread the hose onto the adapter at the oil pickup first and leave it just one turn from fully tight. I could then thread in the adapter and do the final tightening on the hose. I also installed a new RMS seal. Before running the car I rotated the crank several times to make sure that timing was not off so bad as to cause a valve to hit. Finally I installed the flywheel and ran the car to make sure I did not have any leaks. Looked really good!





I bought the Spec clutch from Pelican and I had called them to see exactly what the clutch kit came with as the on-line description is vague. Pelican customer support told me it was only the clutch and pressure plate. But while I had been waiting on their return call I called Spec directly and confirmed with them that their kit also included the pilot bearing, throw out bearing, and alignment tool, which it did.



The pilot bearing included in the kit though was a 6002Z bearing of unknown quality. The Z means that it has metal shields whereas rubber seals would be better in this application. The stock pilot bearing for my 2003 996 C4S was bigger, it was a 6202 bearing with rubber seals. As luck would have it I had a few of these in my shop as it's the same bearing that goes into air cooled 911 steering racks and I had just recently rebuilt a steering rack. So I installed a SKF 6202 2RS JEM bearing - same as stock, but better quality.



I've driven the car now without any issues. As the weather is finally getting colder in Texas I will probably be putting up my 914 daily driver (it has no heat or defrost) and driving this car more. A check of cam deviations with my Durametric tool showed normal, which means I didn't screw up and skip time on the chain with the install. I also don't have any oil leaks. My stress test was to run the car up to 140 MPH, which it did without breaking a sweat. I need to break in the clutch though before really abusing the car, which I normally do as a matter of course, not just for testing.

Overall I am very pleased with the quality of the parts in the DOF kit. The install is certainly time consuming, but not really that challenging. Again, the hardest part for me was just getting the darn transmission out of the tight hole it was in! Installing the DOF was pretty straight forward in comparison.

Now, will I install one on my 2000 Boxster S??? YOU BET!

 

Nice writeup.

Hard to believe that the SKF bearing is less than $11 on amazon, if I have the correct one.

 

Great write-up. I am planning to have the DOF upgrade done to my car at some point. How are you liking the Spec clutch and did you come from the original Sachs (OEM)? What was the condition of your original IMS bearing?

Swaff

 

My car has only 55,000 miles on it, so the clutch I replaced was the original. No real comment on the Spec clutch yet. It seems to function fine, but with some roughness at take-off. The clutch needs to be broken in yet.

The bearing I took out was okay. It had a bit of wobble and the seal looked fine, but inside there was no grease. Even though the seal "looked" fine, all of the grease had been washed out and there was only a little oil in the bearing. The IMS shaft was full of oil too. So... although I don't think that failure of the IMS bearing was imminent, without good lubrication it would have certainly failed sooner or later.

Kirk

 

Hi Kirk:

Awesome writeup - I was really pleased to find this since I'm planning to DIY a TuneRS IMS bearing in my (new to me) '04 4S soon!
I was wondering about your choice of bearing - why did you go with a plain SKF bearing in preference to the Single Row Ceramic Bearing (which TuneRS offers for $200)?
Also, did you need to buy any special tools to remove and install the bearing?

Thanks,
Michael

 

Nice work Kirk Looks like a great option

 

Sorry for the late response, I've been gone on vacation... I researched the bearings and felt that the SKF steel bearing is more than adequate in this application. The only reason that ceramic bearings came up was because of their better wear attributes in low oil situations. The DOF eliminates the low oil issue all together, so a regular steel bearing should work fine. Still, using a ceramic bearing in conjunction with the DOF will add some extra "insurance". If you need that peace of mind, then go for it. I just personally was satisfied with the DOF install and swapping in a new SKF bearing.

I did need some special tools to remove the bearing and to install the new one. I found an LN Engineering IMS bearing tool kit used on Craigslist cheap and used that. You can buy them new though and I think Pelican Parts carries the tool kit.

Kirk

 

Looks like there are several special tools required for this, based on the installation instruction document (which seems quite thorough and complete). A camshaft locking tool, a crankshaft locking tool, a bearing puller and a bearing installer.

I'm prepping for doing this upgrade soon, and am trying to find sources for these tools at a reasonable price. The crank tool looks like something I could easily make, but if there is a pattern out there somewhere, I'd love that info. Any suggestions or thoughts on this would be greatly appreciated.

 

The crankshaft locking tool is really just a pin with a handle on it. To use it I take the handle off to give more room... so it's really just a pin. I'm not sure on the diameter, but I bet you could get the same result with a small screw driver.

The cam locking tool is a special deal and I believe you can get one from Porsche for lots of money! I think on that tool and the bearing removal/install tools you're stuck either with the LN Engineering kit or a copy of it. There are cheaper options on eBay than the LNE kit:

http://www.ebay.com/itm/Porsche-911-...c23b05&vxp=mtr

Kirk

 

Thanks. Anyone on here done this, and want to sell the toolkit to recoup some of their investment?

The camshaft tool looks to me like the real problem. I think I could make the bearing puller and the bearing installer and the crank locking plate.

 

I finally completed my DOF/IMS job. Also replaced the rear main seal, clutch and pilot bearing.

Some lessons learned:

• Grinding a hole in the crankcase of your Porsche engine is not for the faint of heart. I used a rotary burr as shown in the pics above, a cordless drill on a low speed, and lots of fear and trepidation.
• The bolts holding the flywheel to the crank and the bolts holding the pressure plate to the flywheel are NOT supposed to be reused, so buy those before you start.
• The rear main seal is tricky. A 4" PVC pipe reducer worked well for me to drive the new seal in. I learned the hard way that there is no shoulder setting the depth for this seal, so if you whack it too hard, it will go all the way through the bore into the crankcase, where it becomes a rather challenging project to remove. Much cursing and swearing aided in removal of the ruined new seal, accompanied by expenditure of $30 for another new one. #2 Permatex on the outer body of the seal worked well. The book recommends "Curil T" which is quite expensive and apparently not imported into Alabama.
• I bought the LN Engineering toolkit from Pelican. It seemed to have the special tools necessary for the IMS removal and installation.
• You will need a flywheel lock in order to torque the flywheel and clutch bolts to spec. I would NOT use the one in the LN engineering kit, as it it designed only to hold the crank in TDC, not hold it against the torque speced for the bolts. I made my own out of a piece of 1/4" plate about 2"X3". I marked the flywheel gear teeth on a piece of paper, and transferred that pattern to the plate. I used an angle grinder to cut gear teeth into the plate which meshed with the flywheel gear teeth, and drilled a hole for a crankcase/transmission bolt to hold the plate in place. It was ugly, took me about an hour to make, but worked fine.
• The Porsche transaxle is surprisingly HEAVY. I used a transmission floor jack with a ratchet strap holding the tranny onto the jack. It worked well. This thing could really hurt you (or worse) if it were to fall on you.
• You will need a 16mm impact flex socket for the bell housing bolts, and a 12point star head for one of those bolts (bottom passenger side on the 911)
• When its all done, the DOF oil line winds up disturbingly close to the rear sway bar.
• Bleed your clutch slave cylinder when its all back together. I got some nasty looking stuff out of mine.