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LN Engineering IMS 'UPGRADE'

so here's my dilema - my brother has had his 996 about 3 years, was spooked by all the internet stories and had the LN ceramic fitted to his car within the first week of ownership....he was running at about 95K at the time but the car had seen little use over the previous few years.

on inspection he made a good choice as the removed original was almost seized solid! so he was happy...

fast forward 18 months or so and about 2K miles (if that) and BANG! engine self destructs in a BIG way... but it wasn't the IMS causing the failure.

in the meantime, i've bought myself a 100K mile 996 still running the original bearing...

i have the LN out of his old engine (removed with the proper tools etc) and it seems perfect. LN insist that it should never be reinstalled after removal and i need to buy a new one.

so do i fit it?
 
mid said:
so do i fit it?


Noooo. Next time you need a clutch I would inspect the bearing. If its silky smooth with no play as it probably is, flip the seal off and stitch it all back up.

mid said:
fast forward 18 months or so and about 2K miles (if that) and BANG! engine self destructs in a BIG way... but it wasn't the IMS causing the failure.

This just proves it. You could do all that unnecessary work and still something else will fail. Its a 100k 15 year old engine, lots of things wear out / age.

You might damage the old one on removal, damage it or something else on the way in, or be out of line on reassembly.

You'd be even more miffed if the replacement bearing failed....

I've never ever heard of anyone using second hand press fit cartridge bearings in any application, they are single use surely.

If it will help you sleep at night put a new bearing in! Doesn't have to be an overpriced one.

But ooooh what about your main bearings won't they be worn at that mileage? Bores starting to score? Or your vary cam pads? chains stretched much? May as well rebuild and be completely at ease.

If it were me - full rebuild now and future proofing, or inspect and enjoy it till it dies. It might never happen (in your ownership).
 
mid said:
so here's my dilema - my brother has had his 996 about 3 years, was spooked by all the internet stories and had the LN ceramic fitted to his car within the first week of ownership....he was running at about 95K at the time but the car had seen little use over the previous few years.

on inspection he made a good choice as the removed original was almost seized solid! so he was happy...

fast forward 18 months or so and about 2K miles (if that) and BANG! engine self destructs in a BIG way... but it wasn't the IMS causing the failure.

in the meantime, i've bought myself a 100K mile 996 still running the original bearing...

Equally it could of been collateral damage caused by the replacement that instigated the failure I.E damaged chains/tensioners.
What part failed?
 
mid said:
i have the LN out of his old engine (removed with the proper tools etc) and it seems perfect. LN insist that it should never be reinstalled after removal and i need to buy a new one.

so do i fit it?

Never ever in a million years use it .. and i fit these things from new !!!
 
Equally it could of been collateral damage caused by the replacement that instigated the failure I.E damaged chains/tensioners.
What part failed?

we're not actually 100% sure what was the primary cause... my theory is that one piston siezed... i think a ring slipped. this was the only piston that didnt contact valves. the resultant mess makes it difficult to pinpoint any one particular area!

re the LN ims.... i'd pretty much talked myself into leaving alone - and enjoying it until if or when it goes bang... i've always planned on mine being a keeper so even if i park it up for a while and work on it myself its not a problem.
 
The cams were stationary(so likely a snapped chain). The reason that piston didn't hit a valve is because the valves were seated, whilst all the others were open, thus getting wacked by the pistons.
 
.......and snapped chain possibly down to getting damaged when trying to fit the LN bearing in situ. :nooo:
 
alex yates said:
.......and snapped chain possibly down to getting damaged when trying to fit the LN bearing in situ. :nooo:

Pretty much I reckon.
 
I had a strange one in about 6 monthes ago .. Cayman with a snapped chain .. i removed the head on the side of the snapped chain .. nothing obvious but trying to rotate the engine by hand and it locked up .

Something wrong with the opposite side then ..

I removed that head and it turned over fine .. it was carbon build up in the cyls .. compressed carbon is pretty much concrete .. it had built up to the point that it jammed against the pistons and snapped the chain .

never seen it before , i couldn,t figure out the reason for this as these cars dont tend to do this ..well .. its a new one on me anyways .. repaired the car .. not cheap btw and spent ages looking at values trying to figure this fault out .

Didnt get to the bottom of it but its one we are monitoring ..

In essence a snapped chain can be down to different reasons .
 
Never really worked out why mine snapped, original IMS bearing as was still in good nick, the guides and tensioners were fine, it only had around 60k miles so not particularly high miles.

The only thing I came up with is a roller on the chain came off and jammed into the scavenger pump locking the cams and with the rest of the engine still turning it all went haywire. The collateral damage is so much when something like this happens its hard to pinpoint where it all started.
 

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