Roger Rogers

I just bought a used Boxster engine. (100,000 miles) What should I update before I put it in the car. Plan to swap the IMS bearing and the oil separator as preventive. What Are your opinions about what I should take a look at or swap out? (water pump,, spark plug tubes, hoses, sensors?)

Macster

If you do the IMS bearing and AOS as preventative measures then the water pump (and T-stat), spark plug tube o-rings, and at least all vacuum hoses should probably be done as well, "while you are there".

Spark plugs could be due to be replaced and "while you are there" of course you give the coils a thorough inspection. Any signs of degradation and all 6 coils should be replaced.

'course, if for example you have paperwork showing say the water pump/T-stat was replaced not too many miles back and by a reputable shop then perhaps you can skip the water pump/T-stat.

This would be a good time if there is sign of camshaft cover oil leaks to reseal the camshaft covers.

With the covers off then you can look at the cam lobes, lifter bucket faces for any signs of wear. You can look at the VarioCam actuator chain guides, the plastic and if any show signs of excessive wear to consider replacing these.

There is the RMS and the IMS end flange and its seal and bolts. The IMS bearing upgrade might come with a new/improved flange.

With the RMS if you replace this one very important thing (well, of several important things) to keep in mind is to avoid installing the new so its seal ends up where another RMS seal was. The old seal will have worn a groove in the crank journal and if the new seal ends up in the same spot the new seal will leak.

The IMS end flange is generally upgraded at the same time the RMS is replaced. Often an 'RMS" leak is really a leak from the IMS flange. The new flange comes with a 3-ribbed seal and new micro-encapsulated bolts to prevent oil from seeping past the threads. The bolts are partially submerged in oil.

The O2 sensors are not hard to get too once the engine/exhaust are in the car so maybe you can leave this until later. 'course, with the engine out of the car and the exhaust easy to access at this time you can replace them with ease though during reassembly of the exhaust you want to be very careful you do not damage the new O2 sensors. A case could be made to leave the old ones installed and afterwards then replace them to keep the new ones from getting possibly damaged.

And with the engine out and the area open you might as well check the CV boots, engine mounts, transmission mounts, for any signs of any problems.

Schnell Gelb

How do you know the engine even runs well?
Leak down test,noises,water in the oil,debris in the filter/pan....
You could waste a lot of money doing maintenance on an engine with expensive defects
My engine had all the maintenance done but one little defect caused the engine to fail. That required a complete rebuild. I could have bought another car for what it cost to rebuild one engine.

Macster

That's a very good question and one I failed to address. I was somehow under the assumption the engine was sound, but that is a dangerous assumption to make.

Schnell Gelb

Optimism and belief that nobody would sell a defective M96 are admirable.
The problem with my questions is how do you make running tests of the engine in it's current state ? And if you start dismantling it for inspection and find problems ,how do you get a refund?
Perhaps the seller is a reliable source? Optimism ....

Roger Rogers

The engine was said to have pass leak down test. The IMS Bearing is still in good condition. I want to prevent any future problems. The seller has a 98% satisfaction rating on eBay out of 645 reviews. Seems reliable. He suggested that I swap the oil separator before I install the engine.

Macster

It is a problem.

You could just assume the engine will prove to be ok and do to the engine before installation what you think is best with that in mind.

Or you could do the bare minimum which might be nothing other than fresh oil/filter and coolant then with the engine installed use the car a while to confirm the engine is basically healthy/sound and if is is the drop the engine and do all you wanted to do.

Sometimes you just have to go with your gut feeling. What do you feel is the way to go?

Schnell Gelb

98% - that is marginal for EBay. Lets hope you are not one of the 2%.
What were the actual leak-down results ?If unavailable, repeat them.
"Swap the oil separator: - with what ? a new one ? Why? There are lots of components that could be inspected/replaced as Macster carefully listed.
Remove it an look for w/p debris - yes.
But really you need a list of things to replace/check that are difficult to access when the engine is installed.
Speaking of which - how do you know the IMSB is "still in good condition" ?