“New” 914 smokes out exhaust after hard left hand turn. Ideas? Options

[Tdskip]

Happy Sunday folks, hope it’s been a good weekend so far.

Got the shifter squared away, I’ll go back and update that thread in a minute, so I was able to properly drive this thing today and it pulls really well but as part of shaking it down I was really motoring and in a hard left turn the engine will smoke for 15 seconds or so and then clear. Not on right hand turns and not in a straight line, but it does it pretty consistently on a hard left.

I’m assuming that’s related to the oil being forced to the right side of the engine, and maybe getting sucked into the combustion chamber via the head? Maybe? Kind of? Sort of?

[Shivers]

Were the heads rebuilt at the same time? Are these right and lefts in the twisties, or around town. If around town, commonly a right turn does not last as long as a left turn, and I usually will take them faster then a right turn. If the valve guides are worn out it could get in that way. Are you running it high on oil?

[johnhora]

check oil level

[Tdskip]

I am a dope, never occured to me to check the oil.

This was city driving, yes, but sweeping turns at 30-40 mph with a sharp one at the end.

Thanks for the responses.

[GregAmy]

Sure it's not coming out of the tube on the top of the right head, and pouring/dripping down onto the exhaust? I had that problem in the race car. In my case, the tube was not properly swaged in there and it actually came out of the head! Made a friggin mess (incl on the track).

Check that tube, and the hose coming off of it.

[windforfun]

Sure it's not coming out of the tube on the top of the right head, and pouring/dripping down onto the exhaust? I had that problem in the race car. In my case, the tube was not properly swaged in there and it actually came out of the head! Made a friggin mess (incl on the track).

Check that tube, and the hose coming off of it.

Also, go with a high viscosity oil such as 20W-50. I'm pretty sure Porsche recommends this on their website.

https://www.porsche.com/usa/accessoriesands...ights/motoroil/

[Tdskip]

Just click bait spammer, seems like a lot of effort for a likely extremely low click through.

Back to cars - planning on driving the wheels off this one on Sunday, will check oil level etc and report back.

Thanks for the thoughts and considerations.

[barefoot]

Not sure of your engine rebuild history, but if the perimeter seals on those sheet metal splash plates (whatever they're called) are missing or not installed properly, oil might surge up into the pushrod tubes and flood into the head .Since there are no oil seals on the intake valves a sure opportunity to suck oil into the intake ports.

[Dave_Darling]

Doesn't matter if there's a windage tray or not, let alone if the seals are installed properly. Oil still goes up the pushrod tubes in a long corner and fills up the rocker box.

The valve guides are supposed to keep more than trace amounts of oil from being pulled into the combustion chamber and being burned. When they're worn, you can get smoke out the exhaust.

Typically, valve guide wear is worse on the exhausts, because they get exposed to more heat. The symptom generally is that on overrun (high RPM with the throttle closed, coasting, lots of vacuum), the car smokes out the exhaust.

This doesn't sound like valve guides. I would suspect that oil is getting into the intake somehow. The most likely suspect is the rocker box breather, as mentioned above. How are those hoses routed? Might be worth plugging them to see if it helps. Probably a good idea to take a flashlight and look. Check if there is oil on the throttle valve (that's from anything upstream of there) or in the manifold (for anything piped directly into that). A mirror might help, depending on which intake you have, and a borescope might be the best idea. BTW, you can get inexpensive ones from Amazon among other places. Or a mirror can also help you see into the manifold.

--DD

[Tdskip]

OK - happy to repost that I did some more testing via driving like I stole it.

Oil level slightly too full.

Hard left turn held at speed - nothing.

Hard right turn held at speed - oil smoke for about 15 seconds that clears. Looks more passenger side exhaust that driver side but the exhausts enter into a common muffler.

I’m not getting smoke of throttle lift off - so straight line to 5,000 rpm and then lift off does not smoke.

[Robarabian]

I would also suggest pulling spark plugs and identifying if you have one offending cylinder, or more than one. If it is just one, they you are isolating to "why" that particular one is problematic (valve guide, intake issue etc..). If all 2 are bad and 2 are good (hopefully on the same side) then you trouble shoot from there.

[Tdskip]

Good suggestion, thanks @Robarabian

[rudedude]

Is there enough oil in your heat exchanger that flows next to hot exhaust tubing that could be burning off during hard cornering?