Buying car with new (rebuilt) engine?
 

Found a beautiful Boxster S with 64k on the chasis and 4k on new motor. Motor was one of these rebuilt new engines installed by a porsche certified mechanic. Generally speaking, is this a GOOD thing or a BAD thing? How should this affect the price of the car? Owner had an IMS blow and that's why it was replaced. New engine also has an IMS fix that was done at the time of installation. Anything I need to know about buying an otherwise immaculate 986 S ?

Who rebuilt the motor? With what parts? What IMS fix? What other parts were replaced while the engine was out? What year car? Have you seen the paperwork?

A company in California "known for Porsche rebuilds". I can and will get all the receipts etc. The clutch was replaced at the same time and I'm not certain what IMS fix was applied. He did say they had to retrofit the engine, which doesn't make sense if it's the same engine as before, right ? I'm no mechanic. I would still have a PPI but don't want to invest time and money if I should walk away generally on a new engine being used.

My '06 Boxster had a new motor at 73,000 km in '12, and I purchased it at 83,000 km. The previous owner and Porsche split the cost, and then the owner turned around and bought a 911. Since I am planning to keep the car long term, this was not a negative from my viewpoint. So far no issues, but I would like to sort out some time when the engine was built and what model of bearing it has in it.

Did you get receipts of the work etc to confirm prior? This seller, who's a very honest sounding 66 year old Porsche aficionado from what it sounds like, said the car drives even better than before.

Do your homework on the shop that built the motor. Trust but verify. You don't want to be a Motor Meister horror story. Google that phrase

From my own experience a used motor from a wreck (from a vendor with some kid of redress opportunity) made more financial sense after an IMS failure in my 2003 986S. Quality rebuilds were much more $$$ than a used motor.

Mike is suggesting all of the right questions that you will need to answer. The most important thing is to find out WHO did the work and WHAT parts did they replace during the "rebuild".

The truth is that a "rebuilt" motor can mean many different things to many different people. Some engines are called rebuilt when they really aren't.

You want to get a list of every new part that was installed during the rebuild and you need to know what shop did the work.

There are a lot of crap M96 rebuilds floating around and even experienced Porsche shops can struggle with producing a quality M96 rebuild. You want to know how many M96 engines the shop has rebuilt and how well they have performed after being delivered to customers.

Here are my standard definitions for "rebuilds";

Refreshed Engine Some shops call them "refreshed" or even "certified pre-owned" and some sellers will even call them "rebuilt" even though they are not really rebuilt. This option will generally consist of a used engine that has good compression as-is with maybe new timing chain/guides, a new water pump and/or alternator, new thermostat, and a 60K service. Be sure to check which exact parts are new/replaced because it varies. The future reliability of this type of engine is anywhere from 10K-100K miles. Typical cost is $4K-$10K with higher priced engines having fewer original miles and/or add'l components replaced and/or coming from better known shops.

Rebuilt/Remanufactured Engine. A remanufactured engine is where the engine is rebuilt to meet the original spec's, mostly using OEM parts. This is a classic rebuilt engine. Some engines may have updates like IMS/RMS but you'll need to specifically check. This option should give you ~100K miles of service but the reliability is (again) completely dependent on the engine builder and the extent and quality of the updates installed to address reliability issues. Likely to have a warranty of some kind so be sure to check the warranty details. Typical cost is $8K-$12K. Higher priced engines have more high quality parts/updates and/or come from better known shops.

High End Fully Rebuilt The engine is rebuilt from the ground up with mostly new parts and all upgrades. Parts that could have been re-used are replaced with new (like engine timing actuators, engine oil pump and scavenge pumps, valve lifters, valve lifter carrier, etc). The buyer may have been able to specify some build details as desired. Engine is probably better than anything coming straight out of the factory brand new. Shops that do this work are top-end and their business relies on a good reputation. Should expect ~100K+ miles but check the warranty details. $12K-$20K. Be aware that you may not get 100% of the engine cost back in resale value but that really depends on the buyer.