Opinions on IMS Work Wanted

Here the situation- '99 C4, manual trans, 100K miles, market value maybe $20K I have decided to have the IMS bearing replaced (a must according to this months Pano Tech Q & A). This is not a DIY for me. I searched the board and decided I would have local shops quote a bunch of stuff in addition that can be done without removing the engine. Those items included: replace IMS bearing w/ LN replace AOS replace tensioner paddle (crankshaft to IMS) replace thermostat w/ LN part replace oil pump drive shaft replace oil cooler seals replace rear main seal if needed replace cam chains Roughly the quote for all of the above work was $4K. This is rather stiff in relationship to the value of the car. Just the IMS is around $2K Here is what I am thinking. I can DIY some of the other big ticket items- the AOS and thermostat and the other items will have to wait (with execption of RMS, that is on an as needed basis) . My question for the board, especially for the folks that have done the DIY's, iare these DIY jobs (AOS, thermostat) so miserable that even thought they can be done you would advise me to pay up and save myself the grief? Thanks,

Quotes source posts: 9131831, 9131831

You can't replace the crank to IMS paddle without complete engine teardown. I wouldn't replace the cam to cam chains with engine in car myself, although it can be done (engine still has to be lowered significantly to access camshaft covers and remove camshafts). If you plan to have the camshaft covers removed you also want to replace the variocam pads at least and/or actuators & solenoids as well. Thermostat is very easy, 4 bolts and a hose clamp. The only tricky part is dealing with the coolant. You need to drain it first. Then refill it once bolted back together, but ensure that there is no air in the system. Refilling the coolant requires manually bleeding the coolant system properly or using a vacuum refill system (recommended). If it is not bled properly and air pockets remain that can cause hotspots and much larger issues. AOS is a tricky fiddly job, which involves dismantling a good portion of the left hand intake on top of the engine. It is much easier when the transmission is out, and is a $100 part so it might be worth paying someone to do that. edit: I don't see clutch, pressure plate or throwout bearing. If those are near ready to be replaced, you can source a clutch kit for about $450. If you are doing all this for the sake of the LNE IMSB retrofit, personally I would just get the IMS Guardian and not go forward with your plans, maybe wait until your next clutch is due and even then... you have the guardian to warn you about failure. (don't agree with that article about MUST ) Also while the oil pump hex driver is inexpensive, doing this with engine in car is also a fiddly job... but it is do-able. Typically this is something that is replaced during a engine teardown/rebuild.

Thanks, I should have mentioned that the clutch is realtively fresh - 2K miles, but at last oil change I found glitter like, ferrous bits of metal in the oil filter. That is why I am concerned. I should have done the IMSB at clutch change but there is no going back.

Jake Raby has identified the potential problem areas -waterpump-aos-cam chains and tensioner pads -valve lifters and the IMS bearing .In my case I had several lifters that were frozen (114,000 miles at the time ).Since heat can be the achilles heel the low temp thermostat also seems prudent (at least it did to me) . As far as doing these things with the engine in the car -without a lift it would be a real challenge .Since you will have the transmission disconnected and the cooling system drained it isn't much incrimental work to drop the engine and transmissioin as a unit .It sounds more difficult than it really is .

Yeah, you need to include the water pump in that mix if it hasn't been done already. The water pump and thermostat are doable DIYs that I would do again without hesitation. As stated before, bleeding the system for air bubbles is the only pain. If you have ferrous metals in the filter you need to address that ASAP.

$2000 is a little steep for the IMS only. Should be closer to $1500.

If it is a good shop, I dont think thats too bad. But you say your issue is more value of the car vs cost of the repair. I used to worry about this also. Especially when I had a 928. But its the same issue with the 96. I have come to think of it this way; its a toy, I didnt buy it for an investment. I bought it as a toy to play with. Like any toy you are prolly not going to get your money out of it. I stopped worrying about it and made the car part of the family. Iv chosen to keep the car till I can no longer drive it and pass it to someone that can afford to take care of it. Kinda like what you do with that antique pc of jewlwery or rolex.

Going that deep and only carrying out the IMSR isn't smart.. Replace the clutch and any other associated items while you are there. If you found glitter in the oil then you need to protect that engine with the IMS Guardian.. A dozen other wear components can shed the material other than the IMS bearing~

OK, just for a reference point on costs I'll share last weeks bill. Had work performed at Flintworks in Campbell CA. Could not be happier with the shop, service, etc. here is what they did: IMS retrofit RMS Waterpump AOS Front Tip tranny mount Rubber bushing where front driveline connects to tip Some wiring connection on the tip that was leaking slightly IMSG install Bill was about $3300 and this was a tip/ engine out procedure. He had a December special On the IMS retro to generate some biz. Think it was 1250 for a manual trans. Not a fan of grinding for a price on mechanics but you may want to get a second opinion. Per Logray above and Alden at Flintworks, that tensioner paddle is not easily accessible. I read in some thread as you may have where it sounded like that was "exposed" during all this so I wanted to do that as well. Opted not to.