914World.com [Powered by Invision Power Board]

Posted by: webtrader Feb 7 2008, 05:25 PM

Hello all,

I have a question, this being my 1st air cooled flat 6 cyl Porsche I am not sure of something and hope you all can set my curiosity straight.

When I start up my 1971 914-6 after it has been sitting for a day or so, it smokes out the exhaust (blue) for maybe 30+ seconds but then it clears up and runs just fine and when started anytime warm it does NOT smoke?

I am being told by my local PORSCHE shop owner that this is a normal condition for these older flat 6 engines?

Thanks for any comments or help with this question.

LOVE my 914-6

Posted by: appbiz Feb 7 2008, 05:31 PM

911 guy here

Quasi normal, your car has a dry sump and once engine stops you will have a little extra oil in the crankcase, once you start it up it will be tranfered back to the tank, but you will get a little seepage that burns off quickly. your oil filter has a check valve the helps with this problem, if is is really annoying you try changing your filter, the check valve may has some debrise that is letting more oil seep by than normal.
you will find the more days your car sits, the bigger puff of smoke you will see. You will also see more start up smoke if you park up hill and the car is not level for a period of time.
Bob
bob@appbiz.com

Posted by: Justinp71 Feb 7 2008, 06:00 PM

Noticed your in Eldorado hills!

You should come out to EuroSunday in Granite Bay, 8-10am this Sunday at Quarry Ponds...

Posted by: Jeffs9146 Feb 7 2008, 06:02 PM

Normal!

My 67 911s did this but ran like a champ for 10 years before I sold it! I did find that if I changed out the plugs more often it ran a bit stronger for the first 2-3 months before the oil started to build up on the plugs.

In the winter I would change the plugs from a bp6 to a bp7 to help burn the richer fuel for my short drives to work. Never had a problem!

Posted by: webtrader Feb 7 2008, 07:32 PM

GUYS, THANKS for the repsponses and information.

NOW, let me ask what is the best recommended oil and weight of oil to use in my BABY??

Thanks so much....

~Jim

Posted by: Headrage Feb 7 2008, 07:38 PM

QUOTE(webtrader @ Feb 7 2008, 05:32 PM)

NOW, let me ask what is the best recommended oil and weight of oil to use in my BABY??

I run 20 - 50 Castrol in my 2.7 and it seems to do well. I don't run an external cooler and the temps stay between 180 and 210 degrees.

Posted by: Cap'n Krusty Feb 7 2008, 08:01 PM

QUOTE(Jeffs9146 @ Feb 7 2008, 04:02 PM)

Normal!

My 67 911s did this but ran like a champ for 10 years before I sold it! I did find that if I changed out the plugs more often it ran a bit stronger for the first 2-3 months before the oil started to build up on the plugs.

In the winter I would change the plugs from a bp6 to a bp7 to help burn the richer fuel for my short drives to work. Never had a problem!

You went to a COLDER plug "to help burn the richer fuel". That's the OPPOSITE of what you should have done. The Cap'n

Posted by: Cap'n Krusty Feb 7 2008, 08:04 PM

QUOTE(appbiz @ Feb 7 2008, 03:31 PM)

911 guy here

Quasi normal, your car has a dry sump and once engine stops you will have a little extra oil in the crankcase, once you start it up it will be tranfered back to the tank, but you will get a little seepage that burns off quickly. your oil filter has a check valve the helps with this problem, if is is really annoying you try changing your filter, the check valve may has some debrise that is letting more oil seep by than normal.
you will find the more days your car sits, the bigger puff of smoke you will see. You will also see more start up smoke if you park up hill and the car is not level for a period of time.
Bob
bob@appbiz.com

Nice try, but it's wrong. Oil enters the valve guides and flows down into the intake and exhaust ports, along with oil that pools in the lower side of the horizontal cylinders, burning off on startup. If an older 911 doesn't smoke on startup, the guides are too tight. The Cap'n

Posted by: J P Stein Feb 7 2008, 08:14 PM

QUOTE(Cap'n Krusty @ Feb 7 2008, 06:04 PM)

Nice try, but it's wrong. Oil enters the valve guides and flows down into the intake and exhaust ports, along with oil that pools in the lower side of the horizontal cylinders, burning off on startup. If an older 911 doesn't smoke on startup, the guides are too tight. The Cap'n

I have too tight guides then....I can live with it. The pic is not very clear but look at tops of the valves after 6-7 years of running. It does smoke on start up, tho. I'll buy into the Cylinder bit.

Attached thumbnail(s)

Posted by: PRS914-6 Feb 7 2008, 10:18 PM

Yep, normal stuff for a flat 6. Check oil usage and smoking after warmup and pay no attention to the first 30 seconds. I live in El Dorado Hills too. Come to EuroSunday and we can all meet.....

Cap'n.....if it was bad guides, it would smoke when it was running as well. I just did guides in my 3.6. It didn't smoke at all on start up. Come to a quick stop or on a side hill it was terrible...mosquitoes ran!. Guides were worn .015.

Another issue is the ring gaps. They rotate around. If the oil ring gap is on the bottom you will get more smoke on startup.

Posted by: GeorgeRud Feb 7 2008, 11:13 PM

A s far as oil, I've also used Castrol GTX 20w-50 with good success. The folks at LN engineering seemed to do good job on evaluating oils, and I think I'll switch to Brad Penn Oils in the future from their recommendations (Basically they are the old Kendall oils, which have been a long time favorite among those Porshephiles in the know).

My 6 also can be used for mosquito control spraying for the first 30 seconds, then normal.

Posted by: webtrader Feb 7 2008, 11:26 PM

THANK YOU ALL for your answers and advise... I do appreciate it !!

I would love to go this weekend to the event and meet many of you but I will be at the NADA show in San Francisco so I won't be able to attend but I look forward to meeting many of you at a future event.

Thanks again,

Jim

Posted by: SLITS Feb 7 2008, 11:46 PM

I always light a cigarette prior to turning the key ................

The Brown Turd (2.4L ) doesn't smoke on startup.

The Grey Ghost (2.7L) ... well, I'll let you know when I get it started.

Posted by: Headrage Feb 8 2008, 08:21 AM

QUOTE(SLITS @ Feb 7 2008, 09:46 PM)

The Grey Ghost (2.7L) ... well, I'll let you know IF I get it started.

Posted by: SLITS Feb 8 2008, 12:27 PM

QUOTE(Headrage @ Feb 8 2008, 06:21 AM)