Checking the ims bearing (c4s project)

[Alex]

Single row bearings don't have play in them, if they have any, they're goosed. All faces should be making contact with each other.

 

[Harv]

Thanks for the feedback, the IMS bearing will be replaced as there is some play in it.

The new radiators arrived and are shared with the Turbo cars on this C4S which makes replacement more expensive but I found some made by EIS (German) and was offered a very good price for a pair



Fan cores cleaned and tested off the car and seem to function fine



Ah that's better, just need to get some new condensers ordered up



All 4 alloys were in a very poor state so I had the tyres removed and then dropped them off at a local firm for refurb



Tomorrow will be a day of cleaning and re-painting brake callipers (a few of the bleed nipples are seized which will no doubt give some grief) and if time permits IMS bearing removal.


:wink:

 

[Harv]

Can anyone recommended a place that sells black mesh grill as a sheet that I can then cut with snips to fit behind the ABS front bumper grills?

May as we'll protect these new rads by doing this mod while I'm in here!

Thanks

 

[Alex]

I used stainless mesh on mine, no rusting and should last longer than the car:

http://www.ebay.co.uk/itm/Woven-Wir...el-/261141009041?ssPageName=ADME:L:OC:GB:3160

 

[Harv]

Alex

Thanks for that link, they look to be what I'm after!

:thumb:

 

[drabux]

Harv,
I have an IMS bearing puller and installer (used once!) that I'd be willing to sell you.

Cheers.

Alan

 

[Harv]

Alan

Many thanks for the offer, I've sent you a pm

Harv

 

[Harv]

Updates from today...

The new condensers arrived so onto fitting.

I found that most of the old frame to condenser retaining bolts were so corroded that the torx head bolts were useless. A neat trick for extraction is to carefully cut a slot in the heads with a 1mm cutting disc mounted in the angle grinder and then undo with flathead screwdriver. Don't heat the bolts too much though or the plastic housings will melt!!



After a quick clean the new units were offered to the old frames. I noticed the original condensers were painted black and so I replicated this. Perhaps the paint will hold back some corrosion v leaving them bare aluminium as most do. A search through my odds and ends drawer found some aircraft grade stainless steel bolts which should make changing these easier in the future.





Here's my homemade IMS bearing puller, basically a stainless 57mm tube cut to length with a welded cap and hole drilled centrally. A joining piece of bar stock was sourced and tapped both ends to allow it to be screwed onto the IMS bearing stud and then we could pull on this with a threaded rod and a nut on the outside of my fabricated housing. The bearing wound out with no issues





Old bearing as removed and in reasonable condition for 115k miles



The new bearing was spec'd off the old one (serial no 6204 RS1/1). Interestingly the supplier asked about its application and looked up its spec based on running in oil, max rpm not to exceed 30,000!



After removing the dust seals the bearing and install tool were placed in the freezer for a few hours and then easily installed into the IMS tube and circlipped in place





Next time hopefully onto engine re-assembly

:thumb:

 

[mcbit]

An RS1 should only have an oil/ grease seal on one side of the bearing; not a 2RS1?

 

[Harv]

Quite correct, the original RS1/1 bearing only had one seal fitted to face into the IMS tube, this replacement bearing is an RS2 spec but with the seals removed for permanent oil lubrication.

To me it seems if Porsche had fitted an RS2 bearing and outer most the seal failed and broke up it could have gone freely about within the engine... Not good

 

[mcbit]

That wasn't the original bearing the; the originals are sealed either side and filled with grease.

 

[Harv]

Thanks, in which case we have a missing front seal from the old bearing. I will check in the chain chests and sump to see if there's any sign of it.

Perhaps someone removed it sometime in the past?? :?:

 

[mcbit]

By SKF naming convention if it was an RS1 it only ever had a seal on 1 side; the equivalent bearing with a contact seal on both sides of the bearing would be a 2RS1

 

[Harv]

The condensers have been bolted up and look good





While I'm waiting for new IMS flange seals and front brake ducts I've turned my attention to the PSE exhaust. Funds don't permit any replacement so I sourced a section from another 996 3.6 to repair the concertina joint that was badly corroded and blowing on one of the silencer boxes. I managed to section through the old weld with a cutting disc and neatly unpick it and this will make a very nice repair.



Here's the new section given the same unpicking treatment at the seam and positioned ready to be welded in place.



One of the bypass actuators on this XLF option system was stuck half way. With some WD-40 applied to the ball and socket joint it free'd off and I've removed the actuators for cleaning/testing and will attempt to grease the sockets (copper ease perhaps?) upon re-assembly. Notice most of the mounting studs have corroded away.....



I'm hoping to drill and stud penny washers which will then be tack welded in place to solve this issue as the actuators work perfectly.






:thumb:

 

[Alex]

Won't black condensers absorb heat when their job is to dissipate heat, hence the silver finish?