stjoh

Ball bearing is "kul-lager" in swedish (means something like "layer of *****").

alpine003

DennisAN

I suppose I could embellish the quoted NSK press release:

Viper6

This thread clears it all up then, great... what were we discussing again?

Neto

Sounds like this approach of taking both seals out on a single bearing is not a good idea. Just read that the engine of this c4s car went kaboom and the diagnostic was caused by the IMS.

https://rennlist.com/forums/996-foru...ong-story.html

groovzilla

Remember not to do this:
1. Take the easy/inexpensive way out and replace your IMS with sub-par thrown together parts.
2. Sell your car to unsuspecting buyer avoiding disclosure about said thrown together sub-par parts
3. Post on 996 forum that your engine suddenly imploded, mocking the 996 forum
4. Have a fellow RL member dig up this thread and post it
5. Have buyer of car, who just replaced engine, read this thread and begin a possible lawsuit with the help/support of fellow RL members

sweet victory

Adding this post here as well so others do not make the same mistake.

The information I'm about to talk about is not in the spec sheet. I had to use one of my textbooks from college to get this information.



This chart is used to determine your dynamic and static load rating for an equation used to figure out the life cycle of a bearing. Before I did any math, I noticed the load ratings are very similar, indicating to me the bearing KK used appears to be a 02 series deep groove ball bearing.

All bearing part numbers are made up of a type code, series, and bore. The second digit is what we're interested in as that indicates the robustness of the bearing. A number 2 series bearing indicates it should only be used for light duty applications. The item ID for the bearing used is 6204. The 6 indicates it is a roller ball bearing, 2 for light duty, and 04 for a 20mm bore. (Except for 0 through 3, the bore size is simply five times the third and fourth digits together) The spec sheet and item ID lead me to conclude the reason the bearing failed is that it's only a light duty bearing. As a mechanical engineer, and a human being with common sense, would not recommend this bearing for this application.

Paul Waterloo

Please do not pay attention to the information above, it's just wrong. And I'm not a mechanical engineer, but I know this. I come the school of hard knocks.

sweet victory

Your inability to articulate yourself and provide any discussion is a real testament to that.

Paul, everything I stated in that post was fact except where I said I would not recommend using a light duty bearing. Bearing nomenclature is a standardized process. 6204 bearing is a standard item that nsk, skf, ***, etc. all make. They may all have unique suffixes at the end of it, but this number is a standard item. I've done nothing but regurgitate information in that regard.

Why did I recommend not using a regular 6204 bearing?

The only two people who've ever used this bearing had the bearing fail and BOCA bearing, the manufacture, advised against using this bearing for this application. The SKF 6204 bearing spec sheet provides a fatigue load limit of 0 .28kN. That is roughly 63lbf. That means if you want the bearing to reach it's 'full life cycle', you cannot exceed this force. The cyclic loads coming from the chain and sprocket will easily exceed that. You combine that cyclic load with the engine vibration, and you will set yourself up for trouble. You can have 6204 bearings that have a modified internal design with the same boundary dimensions. The bearings used here do not fit that description.

Schnell Gelb

The other issue is the ABEC rating. The stock bearing is C3.
Tighter tolerances are available but are not necessarily better in this IMSB application.Thermal expansion is cited as the reason.Who knows? Not me.
If the bearing is a counterfeit/fake/sub-standard then all the part numbers and specs are useless.
So the interesting challenge is first to find a source of bearings that is not counterfeit.
The interesting cheap compromise for the load/lube argument is to fit a cylindrical roller bearing with Pedro's DOF ? Assuming the bearing s not a fake ! BTW Pedro's the single row bearing in his kit was "SKF Made in Argentina".

MajorMajor17

I have gone with the Pelican ims bearing kit.....will do it again with next clutch, trans service...
I have a LAN tool, My question...
If I use cam locking plates and TDC locking pin, do I need to use set screws for the intermediate shaft sprocket? And if I have to, then I may have to rotate the intermediate shaft so the sprocket flats line up with the set screws.... can't keep the Motor, cams locked up at TDC. And....the chain tensioners...... loosen after the locking plates and TDC pin is installed? It may seem silly, but skipping a tooth trying to replace the IMS is not what I want to do.
Thank all

pfbz

This is a thread you probably didn't want to reopen.... Some history here.

Try starting a new thread on your installation question, you might bet better results.

MajorMajor17

Thank you