Van

Well, during the last 2 or 3 engine starts I've noticed a some oil smoke - which was never there before. And today I had to back the car out of the garage and while it was idling in the driveway, I noticed a distinct knocking sound...

The poor engine might not be much longer for this life. However, I've had the car nearly 8 trouble-free years and 55k miles. It's a '99 C4.

We'll see what happens, and I'll keep everyone updated.

I was just looking on ebay, and there are 3.4 liter Boxster engines in the $4-5k range... Any reason why that wouldn't be a "bolt-in" - accounting for the accessories and intake plumbing?

Jake Raby

Did you drive the car in cold temperatures this winter?

johnireland

Just guessing but putting the engine in the middle of the car vs hanging out the back might create many different issues. Exhaust, motor mounts, transmission placement, coolant system, I think looking for a 911 transplant would be more efficient.

ejs1

Jake, can you elaborate on what you mean by driving in cold temperatures? Are you referring to cold starts or even driving in cold temperatures even after a warm start? I assume your point is bore scoring and how cold temperatures impact it... What is 'cold' in your textbook and what advice would you give to people who drive their cars year round in 4-season climates?

Thanks

Van

Indeed - lots of times... What's your theory?


Yes, of course - that's what I mean by "accessories". I mean, is the basic long-block the same from an M96 Boxster as an M96 996. Clearly, if I take the engine out of my 911, I have the exhaust, intake, engine mounts, etc. ready to bolt onto a new donor.

Barn996

Say it isn't so Van. Hoping for the best with fingers crossed for you.

gricec

There is a thread on here about someone putting a boxster s engine in the back. It can be done, I dont think he had too much trouble.

mikeborden

From the pic, is your car showing a little over 169k miles with original engine?

Jake is asking because these engines typically will score bores more frequently if driven in the cold, well cold startup that is.

Was your car sitting up for a while? It could be a lifter as well instead of a scored bore.


Mike

dgjks6

http://www.pelicanparts.com/techarti...ngine_Swap.htm

If it works one way it should work the other.

Van

The engine was replace right before I got the car at 105k - so this engine has about 65k.

It doesn't sit much - I drive it at least every other day... but that does include some super cold weather.

Usually a lifter is more of a "tick" noise, but this is definitely more of a "knock" noise... Oil pressure is still good; coolant temp is good; it's running well otherwise... But something is amiss, I can just tell.


Good to know!

Macster

Rod knocking is rare. Before you blame a rod for the noise and condemn the engine be sure a water pump isn't failing.

Or with my Boxster a converter brick was loose. It would generate a deep bass knock upon cold start. Warmed up the thing would buzz like a heat shield was loose.

Once warmed up I can even hear what sounds like rod knocking from my Turbo. Turns out the noise is from the gear box, the rattle of the gears on the input shaft. When I depress the clutch pedal the noise goes away.

Imo000

I remember that one and it was a very easy transplant.

roadsession

I had a loud rocks in a drum knocking sound that I thought was IMS related. It was a broken catalytic converter.

johnireland

There is a recent thread here about Porsche now selling short blocks because the 996 now qualifies for their "classic" parts support.

Van

OK - thanks for the suggestions. When I get a chance I'll do some more sleuthing and see what I can deduce.