cds72911

I would think the LN IMS Retrofit would be a good choice if you're working within a budget. While the LN Solution would be great, the Retrofit has been working well in a lot of engines. It buys you a few years to decide if you want to do another Retrofit or the Solution at the next service interval.

Rdrcr

^^^^
That's what I'm hoping.

Mike

jumpy chunky

Do you know the S/N of your engine?
May not be the cars original? That might make a difference.

Rdrcr

Yes! M96/0166X06876

I'm pretty sure that's the original. 1 owner car before I purchased with all service history.

Mike

jumpy chunky

Okay,. That number looks correct for a '99'.
Sounds as though you have all the records for your car so you would know what has and hasn't been serviced.
Don't know your mileage, also not sure if anyone advocates replacing the dual row

Rdrcr

I just turned 100K miles.

The factory IMS has never been replaced and that's precisely, why I'm asking 'IF' I should even consider replacing an OEM dual row...LN Engineering suggests that the IMS bearings is a serviceable item and should be replaced every 6 years or 75K miles. If that's correct, then I'm assuming I 'should' replace it.

Mike

cds72911

Personal decision.

I'd look at the probability of an adverse event and the impact if it happens to figure out the risk. It may be low likelihood, but the cost to repair/replace is high. For me it is worth the cost of a periodic bearing replacement to mitigate that risk.

Rdrcr

^^^
And, that's kinda what I'm thinking. We're gonna take a peak at the 100K mile OEM clutch. I'm thinking if the clutch needs to be replaced...a new IMS bearing will be going in. Just like a new AOS...

I just want to make sure I'm not crazy if I replace a factory dual row for an aftermarket bearing...

Mike

808Bill

Just change it, it's not worth the risk and clearly you're not in a financial situation to do a full rebuild should it fail.
What's your budget for all this? I know of a 40K mile 3.4 that's still in a car running well if needed.

Rdrcr

^^^^
Thanks for the suggestion!

I believe we're gonna be right around $7K with all the work going into the engine (all new valve springs, all new lifters).

Mike

Rdrcr

Update:

I stopped by Dundon Motorsports this morning to survey the top-end damage.

One intake valve spring is in fact broken. One intake valve is bent. And, the Oil Scavenging Pump is broken (the drive shaft broke off in the camshaft).
Jacob told me I'm lucky. He's never seen one of the oil scavenging pump break like this and not destroy the engine!

So, next, the head is coming off for further inspection and I do have some timing chain guide wear. So, those will be replaced too.
In addition, the clutch, flywheel and slave cylinder require replacing as does the nasty looking AOS.

Mike

Porschetech3

I have seen the scavenge pump drive break off quite a few times, but he is right, you are very lucky, more commonly when a piece of valve spring or ect. locks the scavenge pump,the timing chain will break or the IMS gears will slip on the shaft , this causes pistons and valves to collide and catastrophic failure immediately !!

Since having the scavenge pump drive break is really the best case scenario, I have often thought it would be best to cut a fault line across the scavenge pump drive to ensure that in the event that the pump locks, the drive will break instead of the timing chains and IMS , sort of a "mechanical fuse" if you will, to protect from catastrophic failure. The scavenge pump is very easily replaced...

Rdrcr

^^^^
I was wondering which failure occurred first but, yeah, that makes sense. I know the valve spring keeper(s) are missing, the retainer looks like some material has been removed and who knows how many small pieces came off the valve spring. So, I could definitely see any of that material locking up the scavenging pump. Dang. I'm glad more damage wasn't done.

I'll report back once the head comes off and if there are any additional items that need attention. Plus, if I have an opportunity, I'll add pictures of what was found.

Mike

808Bill

We love pictures!

Rdrcr

Broken valve spring.

Mike