Blowing oil update #3. NO broken rings - Page 3

911pcars · 01:08 PM

Chris,
I was talking to Gene Scott who races his red '67 911 in VARA (father/son act featured in Excellence) about this a couple of months ago. The younger Scott, Mark, was having venting problems similar to yours (large quantities of oil in the catch tank). This was described in some threads related to this a few months ago. Their solution (I think it was successful) was to add additional baffling of some sort inside the oil tank to help separate blowby and oil mist.

Maybe Mark will see this thread and respond with some insights.

As an aside, Honda made an attempt to reduce piston ring friction in their turbo F1 engines a few years ago by deleted the ... piston rings. They thought a few pounds boost lost through add'l blowby was worth the reduction in high speed friction. They had too much blowby and went back to their previous design.

Sherwood

Wayne 962 · Wayne 962's Garage

Jerry Woods (or Bruce, can't remember) old a story about a stock 911SC than ran itself out of oil, because the oil pump couldn't scavenge as fast as it was using it. After driving for many hours straight at high speeds (in Germany), the car completely ran out of oil. It all got stuck in the bottom of the engine...

-Wayne

cstreit · cstreit's Garage

Yow! Wonder how long it took to diagnose!?

911pcars · 06-10-2003, 10:01 PM

"Yow! Wonder how long it took to diagnose!?"

Not long I'm sure. The solution is in Bruce's book!

Sherwood

Wayne 962 · Wayne 962's Garage

Has anyone really read Bruce's book cover to cover? I typically get frustrated after about 10 pages an skip around. Then again I have the attention span of a

cstreit · cstreit's Garage

...hummingbird. Me too.

I've generally picked a chapter to read, rather than cover-to-cover, unfortunately it's always the same chapters.

So I'm struggling with what I could have done differently to help seat my rings faster. I would have thought that by 400-500 miles they would be done, but it seems maybe they weren't... ...and that the racetrack would have helped seat them faster. Possibilities that a too rich mixture could cause this?

jgparker · jgparker's Garage

Easy now, Bruce was rebuilding 911 engines before you were born. I personally love his book. I've read it several time straight through, and was first in line to buy the second addition when it came out. He has the depth of experience in the subject that few come close to, most of which is hands-on. I don't like the formatting of the book, but that is just a style issue.

Wayne 962 · Wayne 962's Garage

I've talked to the folks many times at Motorbooks about the layout of Bruce's book. The good news is that the third edition seems like it will be laid out better. The info is good, but the layout is horrible. If you've read the first edition, you'll see that the layout of that book is much better - they just randomly cut and added stuff on the 2nd edition.

Chris, yes, having too rich of a mixture can delay the seating of the rings. Did you run your compression, leakdown, and HC test? If all three come back okay, it's not a rings issue...

-Wayne

911pcars · 06-11-2003, 10:30 AM

Chris,
Back in one of the early threads, you observed some light vertical scoring of a cylinder, and I thought this might be due to an overrich mixture, perhaps washing oil from the cylinders. I don't know if this contributed to the rings not seating or not, but the A/F ratio is something to check/consider.

If the rings don't seat and blowby persists, I would contact CE and/or other reputable engine builders and get their opinions on how best to proceed.

Sherwood

speeder · speeder's Garage

The copy of Bruce Anderson's book that I have, (2nd ed.?), is filled w/ great information, but finding any of it would require a CIA analyst. As a reference book at your side in the garage during a rebuild, it is about as useful as the 2nd edition of "The Joy of Cooking/Sex/Cooking with Sex".

I consider it more of a great bedside read, like a Russian novel for Porsche geeks, w/ everything you would ever want to know hidden amongst anecdotal stories about wierd repair jobs seen over the last 40 years.

911pcars · 06-11-2003, 11:11 AM

Books that impart information and data MUST have a comprehensive TOC and index section, otherwise they're less useful as a reference source.

I'm not sure how widespread this remains, but many factory repair manuals did not contain an index. Unbelievable. And they wonder why their techs never/seldom use them. BTW, ever try to find some information in the Porsche manuals? I haven't seen the latest ones, but the big buck, multi-volume sets for the 911 are in the above category. Great info, poor format.

Sherwood Lee
http://members.rennlist.org/911pcars

jcbear · 06-11-2003, 03:18 PM

I agree with Speeder, great information, lousy arranging of material and formating, most pictures have little or no relationship to the surrounding text. You do have to read it completely through in order to find all the tidbits of good info. It was and Still is a good source of information on making upgrades / modifications to an engine; HOWEVER, the early 2.0,2.2, 2.4 mod's are around page 137 (in his second edition) but the info on camshafts to go with those mod's in tucked away in a little section on camshafts on page 188 - go figure?

Only wanted to a make a comment to reiterate how much WAYNE's efforts to put a FANTASTIC PRESENTATION OF MATERIAL, WITH GREAT PHOTO'S, ARRANGEMENT OF REFERENCE DATA, ETC. INTO HIS REBUILD BOOK.

Bruce Anderson has incredible knowledge of the history to the development of the car, from his years of PCA Tech articles (still available in Fix'en Up Der Porsche printed volumes), he is sort of recognized as the general USA ambassador for Porsche, one of two speakers in the DVD 'The Porsche Story'.

I really wish I had known about Bruce Anderson's and Jerry Woods rebuilding class BEFORE Wayne told us all about it!!!

My additional 2 cents -- Let's keep the forum FOCUSED on ENGINE REBUILD stuff, please.