What should I do to the engine while it's out?
 

So, I'm reasonably certain that my intermix problem is a cracked head. I have rechecked the new oil cooler and the new o-rings. All look fine. I have re-flushed it again and again - I still have oil in the coolant. I can't think of anything it could be other than a cracked head. Assuming that's correct, my plan is to remove the engine and send the affected head off to repair.

While the engine is out, my plan is to replace the engine and transmission mounts, the rear most cats will be replaced with cat delete tubes (they're rattling like crazy when hot, and it's internal, not the shields), replace the IMS bearing, the clutch, inspect and replace the flywheel if necessary, the AOS, and all AOS tubes and oil fill system lines and hoses. Of course I will give everything a good cleaning as well. I'm thinking that with 105K miles on the engine already, I'll use the Pelican IMS bearing kit. The others are just unjustifiably expensive.

Am I missing anything else I should look at replacing while the engine is out? I don't know much about the chain tensioners and pads - are these easier to do with the engine out, and should I look at replacing them? The engine does have the usual rattling temporarily on cold start, and it quickly goes away. The water pump was just replaced, so I'm good with that. This is NOT going to be a fun job. :mad:

It all depends the condition of the engine before the head cracked and how long you hope it will run. The longer the hope the more things on your list are worth doing. If it's really long, go with a better IMS option. My order would be IMS/clutch/flywheel, variocam pads, chain tensioners.

Maybe set of NHP 200 cell headers, or at leadt an exhaust stud manifold conversion. Probably easier to do that with engine out. Saw a post about the stuud conversion recently.

If your flywheel is original, just plan to do it. Of course, RMS too. At 105k I’d probably opt for the Pelican, or even Porsche IMS. Technically, I don’t think your engine would “qualify” for the “solution”. Tensioners for sure, you are right there anyway, possibly pads. Might be worthwhile. Coolant bottle maybe? How is your trans? Any second gear issues? If so, might want to think about that too. Might not be fun, but you will learn a lot and it will be rewarding once you get it all dialed.

What's the issue with second gear? These cars have so many "known" issues I can't even keep track. This is a new one to add to the list. Can you please explain what's up with second gear? I have no issue with it that I'm aware of.

motor and transmission mounts for sure. They make a world of difference when new.

Some cars pop out of second gear and there is an aftermarket detent available to make the gear engage more and no longer pop out. If your car isn't popping out of second gear you don't have the issue.

The motor mount of course. When I did my engine, the trans mounts seemed fine. While it's out, spark plugs, coils, renew and regrease the half shaft boots--clean the grease out of the cv joints and pack with the grease that comes with the new boots.

New hoses as needed--I had to replace 4 way hose (tiptronic) and replace the little hoses that connect the coolant bottle manifold that goes thru the rear firewall to the small metal tubes that run next to the engine on the passenger side.

While you've got it all apart, maybe an underdrive pulley, certainly a new fuel filter. And I put a spin on oil filter converter and am now using cannister filters. A magnetic drain plug, too.

While you have it up on a bench or a motor stand, I'd pull off the sump and really give it a thorough cleaning and inspection.

You are a braver soul than most of us to be pulling a head off for recon. I bought a different engine to avoid doing that.:chicken:

Keep us in the loop, and take pics. Good luck!

Coolant reservoir. I didn't do mine when the engine was out and now every time I walk past the trunk a hear a quiet "tick tock" from within. In fact I'm twelve miles away from the car and I can hear it from here.

Vacuums lines, reseal the oil pan and clean oil pickup line and replaced o-rings. Replace AOS plastic lines and associated o-rings, at this mileage they are all brittle.

Lastly, clean your radiators this is why you have a crack head. Separate the condenser and water cooling radiators and clean the fins. DO NOT use pressure washer, spray water directly and perpendicular to the Radiator, faucet pressure should be good enough.

Did you check if your water line rubber hoses are not oil damage?

Good luck

Just slap a 3.4 motor in!!!

As mentioned the second gear pop out... fairly common. Also, second gear synchros start to die, see first issue, and then you get second gear grinding while trying to shift. If you are not experiencing this, not to worry. But do your tranny fluid with Porsche blood of you haven’t already.

AOS, easier when it is up in the air with the trans out

I didn't see the year, but it sounds like you have a dual row bearing. If so, I would recommend against the pelican kit as it is a single row bearing with a spacer. I would simply source a high quality dual row bearing over the internet and use that as the replacement. Bearings, like nuts and bolts, come in standard sizes. For my rebuild which is a single row I used the bolt from the pelican kit, and sourced a different single row bearing to work with a modified IMS.