2.7 engine Smokes

[pat9146]

I had my 2.7 engine rebuilt about 6 months ago. Every time I start it after it sits overnight I get a big blue puff of smoke. It eventually quits. Sometimes it will do the same thing if it sits for 5 or 6 hours. Is this normal? What could be causing this? and how can it be fixed.
This is really annoying since I have $12K invested in the rebuild.
I really appreciate an answer. I am not a mechanic so easy terms would be greatly appreciated.

Thanks

[Henry Schmidt]

Most likely piston ring problem.
If they are new pistons and cylinders you could be having ring seating problems. If the Ps&Cs were used they could be out of spec or new rings in used cylinders can also have seating problem.

What kind of oil?
Ps&Cs new or used?
How did you spend $12,000?

Cheers

[pat9146]

Henry,

Thanks for replying. The pistons and cylinders were not replaced. They said they were good. Put new rings in.
How did I spend the $12K?
It started out having pulled head studs. Case was shipped out to Reno and had timecerts installed. Cam was flaking so I had it welded and hard ground, new (rebuilt) cylinder heads, and other internal parts (chain, seals, gaskets). Put together and had a huge oil leak. Tear it apart and fix that but found out when they put it back together and ran it that the crankshaft was frozen. Tore it apart and replaced the bearings for a second time and sent the case back to Reno to have it line bored. Put it back together again. I paid for all of this but I didn't think I should have. Now it puffs a big blue smoke screen when I start it up, leaks oil (this will be the 3rd time they are trying to fix it). This is coming from the nose end. They have put 2 different sleeve in and it still leaks. I also have a knock in the engine. I was driving down the road on Friday and it just stopped running. I got it started again and it died several more times before I could go anywhere. I just took the car in and told them I will be happy when it doesn't smoke, leak oil and there is no knock.
What do you think about the knock? Any ideas? I am not happy and feel that they don't really know what is going on.

Thanks

Pat

[Henry Schmidt]

Used pistons and new rings are a formula for disaster if not measured and prepped properly.
Oil leaks are part of the Porsche reality. Anyone who builds a lot of 911 engine will encounter an oil leak sooner or later.
The sign of a quality technician is how quickly and effectively that oil leak is dealt with.

As for the knock, rods knock, pistons can make a knocking noise, loose valves can make a ticking and if loose enough it might sound like a knock. On a fresh rebuild by a questionable tech. a rocker shaft that has shifted position can sound like a knock.

If the timing has changed you can get a severe detonation that might sound like a knock.
That all I have with the information you offered.
Good luck.

[pat9146]

Henry,

Thank you for all the information. It is very helpful to me to understand what the possible problems may be.
I really appreciate it.

Thanks

Pat

[Wayne 962]

Who did the assembly?

-Wayne

[afterburn 549]

My ohhh my.....12,000!!!!!!!??????......well anyone can make a mistake, its what they do after that makes them good or bad.
I believe for the $$ paid you should have had new pistons and cyl with the rebuild.
I would like to know "who" too even if you have to pm me

[pat9146]

At this time I would rather not say who it is. Obviously I am not happy but I want to see how they handle it. I told them no smoke, no leak and no knock. All I will say is that it is no one in California. It is someone in Illinois.

[afterburn 549]

like I say,if they stand behind it even at your inconvenience they are ok .
Everyone makes mistakes

[pat9146]

I agree. I do not want to smear anyone. They know what I want and if they can deliver then I don't have a problem. It is inconvenient.