OK, that is a Click Bait title. Yes, I am embarking this week on a new journey for me, a complete rebuild of the flat 6 engine on my 07 Porsche Cayman S. I am 2 1/2 years into the restoration of my 63 FHC and, as has happened before, there are circumstances where I just need to jump out of that project for a while. This is one of them. I’ll still maintain movement there, just not my full time attention.
This is the same Cayman featured in my Road Trip articles last summer. I bought the car almost 2 years ago with almost 100K miles and my being the 5th owner. These cars can be very reliable. But there is enough anecdotal evidence of problems showing up with older cars being introduced to track duty (my intention) that I will just sleep better with a engine refresh completed. Replacement engines are getting hard to find. As I say on the Porsche forum, we seem to be blowing them up faster than we are wrecking them. A rebuild will not be cheap but once you gernade the engine, things get really expensive.
Just to state the obvious but modern cars have all been pushed closer to their limits in the quest for fuel mileage, performance, air quality, and cost. And yet we never think “Oh, it’s time to rebuild my engine” on our modern cars, as the engines tend to outlast other things to the point that we sell the cars and move on. So maybe I am being overly cautious but I guess that is the way I am wired. Anyway, I’ll be posting a series of articles to my website as I go along. If you are interested follow along. I do plan to do most of the work myself.
Harvey
In some area’s high time engines are considered reliable and most failures occur shortly after rebuild
My 2 cents ……your looking for trouble that engine should outlast you easy, stay focused Finnish the Jag before taking on another.
I’ve got several friends with hangers full of unfinished projects there spread to thin just saying
Cheers
A friend of mine has a 993, which is, by a MILE, the BEST 911 I have ever driven. But, about 10 years ago, he had several problems with the heads, which necessitated replacement. Factory heads were non-existant, even good used ones. He spent a bloody fortune (~$15K!) having a full set of heads CNC machined. But, alas, they were short-lived, due to some design or machining mistake. I forget the details. He had to do it again, for another ~$15K, and this time it turned out OK. It is amazing to me that Porsche does not keep a better stock of replacement parts for a car that was, at that time, only about 15 years old.
Jim, I understand your concerns. I truly believe this is the best use of my time, which should only be a matter of a few weeks of actual wrenching, aside from long waits for machining. A blink of an eye in an Etype restoration sense.
Ray, a short block is available from Germany for the bargain price of $22K. I’m not going that route but it is a possible contingency. I have already investigated and all the parts I need are available, although supply chain issues are always lurking. I don’t know the cutoff for parts support but the Cayman has not reached it yet. I bought an entire interior carpet set and a headliner last year, so their support goes beyond typical maintenance items.
David, here is a blurb from LN Engineering that answers your question.
How to Prevent Porsche Bore Scoring
Car engines contain a large number of components made from aluminum. In your modern watercooled Porsche engine, this includes the pistons and cylinders. Aluminum is lightweight and versatile, but it has its limitations. For decades, Porsche used a durable Nikasil plating for the wear surface of the aluminum cylinders, but in Boxster, Cayman, and 911 engines, Porsche chose to use hypereutectic Lokasil and Alusil engine blocks instead. For this reason, over time, your Porsche may experience bore scoring or cylinder bore scoring.
WHAT IS PORSCHE BORE SCORING?
Porsche cylinder bore scoring occurs in engines with Lokasil and Alusil engine blocks when there is a breakdown of the Aluminum-Silicon (Al-Si) cylinder system. When the required iron-clad piston coating fails or there are insufficient exposed silicon particles on the face of the aluminum cylinder bore to support oil film formation, there will be accelerated wear on the pistons, rings, and the cylinder walls. As the pistons and rings move up and down the cylinder, wear debris will be dragged through the bore, causing cylinder bore scoring.
Might be a case where engine pre heat might pay off ,guys getting on it before temps are stable?
I don’t know much about Volkswagen Lol other than I went skiing with a friend in a old bug ,told him next time we take the 5th Avenue
Your a smart fellow Harvey I’m sure you have it figured, thinking I’d buy the parts before taking it apart as there probably not available at Napa etc
Cheers
Thanks Harvey. Not long ago I saw part of a show where they were dealing with the bore score problem in a Boxster and saw the type of photo like you posted. My other cars are Chevrolet Vegas and I know lots of folks had oil usage problems with them with the same type scoring. I knew Porsche and Mercedes later adopted the same type of high silicon content aluminium alloy that the Vega introduced for some of their liner-less blocks but when I did a quick google search I could not tell if the Boxster was one of them. With the Vega most of the problem was from hot running and poor coolant /oil maintenance so my father and me always fitted ours with larger than stock radiators with great success in our Texas Vegas. Somewhat recently I saw a discussion with a GM engineer and he said the piston plating to make them compatible with the silicon bores was often too thin especially on the pre-1976 Vega and could wear off prematurely if engine was pushed hard prior to warm up. My father also taught me not to push any engine hard before it was thoroughly warmed up so that may be another reason we had such success while lots of other folks had problems with their engines. I worry about the XK engine too with it’s aluminium head / iron block and different expansion rates if things get too hot so soon after I bought my E it also got a new radiator and Coolcat fans.
Well, phase 1 is complete! Wow, no rusty or stuck bolts. But I am convinced that Porsche used every possible type of electrical connector, just to keep me guessing. A more in depth article for my website is being prepared.
Harvey, I truly admire your ability to ‘change gears’ I have a tendency, for better or sometimes worse, to become monomaniacal with these cars. That being said a Citroën SM can take a lot of time and my E Types have been quietly waiting…
Cheers and good luck with your project.
LLynn
Harvey,
I will be following this thread as I also have a 2007 Cayman S that I have owned since new. Your Cayman appears to be the same color as mine “Atlas Grey”.
Good luck on the rebuild, and keep posting your progress.
Bill.
Harvey,
How do you like the single post lift? I almost bought one about ten years ago but worried that the arms going under the car would be in the way. With where I am now, I limited to my floor jack and jack stands but that’s hopefully changing soon.
Dave
The bar across the middle does indeed get in the way for some activities. That said, the ability to move it around the shop (it uses a pallet jack principle to raise it off the floor and it can be moved single handedly almost anywhere I want to go) is a strong advantage for me and easily offsets the other issue. I admit that I do feel some unease when I am under a car overhead but frankly, even with a two post lift, you are at the mercy of the quality of the construction. I tried to get a “name brand”, although they are all probably made in China.
I will tell you one thing, pulling the engine on a Porsche, which by default has to go out the bottom, would be well nigh impossible without a lift. Oh, my 20 year old self would have made it happen with floor jacks and concrete blocks but the lift makes it so easy.
When I was shopping for my 2-Post Lift, one of must-have characteristics was that it have an ALI certification. It added about $1,000 to the overall price but that is cheap insurance. My Challenger SA10 (*) has a sticker on it saying Made in P.R.C. – but it also has an ALI sticker.
(*) More lift than I’ll ever need, but the lift I wanted was back ordered and then discontinued. In consideration of the several months I waited, they gave me the next better lift at the price of the lift I wanted.
