dark smoke from the crankcase breather

[twobone]

Maybe its normal, but there are light puffs of smoke coming up from the base of the engine where the crank case breather hose is.

 

Its more prevalent asround start up.

 

Is that just the nature of a these engines? The car only has 24000 miles and the exhaust is not smoking. Perhaps its just running a bit too rich?

[gjslutz]

I would think a broken ring. Too rich would be out the exhaust with smoke.

 

I would do an compression test and also read the spark plugs.

 

If it is water, I would think a head gasket. If oil, likely a broken ring. A broken oil ring would not show up on the compresson test, but a compression ring would show up.

 

If it is valve guides it would smoke out the exhaust.

 

This is just a quick idea.

[TheDingo8MyBaby]

Or your sump may just be overfilled. Some crossflows have oil surge problems. Most people take the easy way out and simply add more oil..

[bsimon]

From your other posts and pictures I assumed your engine was dry sumped.

 

That being said, there should not be any openings/breathers that would show any smoke. The engine should only have one breather hose that runs from the rocker box cover to the top of the oil tank. The second hose on the top of the oil tank should run to your catch can. If there is any crankcase smoke, it would come out of the catch can.

 

All blow-by (smoke) should be sucked out of the crankcase by the scavenge section of your dry sump oil pump and deposited into the oil tank. It will then find it's way to the catch can. The rocker box hose simply relieves the crankcase vacuum that the pump creates.

 

If there is some type of crankcase breather outside the DS system, I'd venture that you have a plumbing issue.

 

Light puffs of smoke from the catch can, depending on magnitude, is somewhat normal for a well broke-in Kent block motor.

 

Monitor your oil consumption and catch can returns to determine if there is something more serious going on.

[twobone]

What is the purpose of the catch can?

[MHKflyer52]

It catches the oil vapor and lets it collect plus it contains any overflow of oil or any fluid from getting on the car and more importantly the road surface or track surface.

Edited August 2, 2010 by MHKflyer52
added words in red

[bsimon]

The catch can keeps the various automotive liquid discharges from contaminating the track surface,

(If you're an Enox, it keeps the environment pristine.)

[twobone]

looka like the previous owner did not install a rocker cover with a breather tube when he did a dry sump conversion. The tube at the top of the oil tank just leads under the car. I will look for a proper rocker cover and see if that fixes things up. Thanks bsimon

[twobone]

I checked with Burton power and it looks like the dry sumped xflow rocker covers have no vents.

 

I have attached a pick of the hose in question (circled in red). Where is this suppossed to vent? Directly to the atmosphere?

 

BSIMON, do you have a picture that will show where this is suppossed to route?

[bsimon]

On most DS systems, that connection has a hose that runs to a catch can. If that's an Easy-Clean two piece split tank I see in your photo, it will probably be a 5/8" hose. Run the hose to an open top receptacle mounted upright somewhere in the engine bay. Just stick the hose in the top of the catch can with no fittings. The annular space between the hose and the receptical's top opening allows the system to breath.

 

If your windscreen washer bottle is not used, it makes a good catch can. I've seen those fancy 1 pint aluminum Budweiser "bottles' used as catch cans as well. Be creative.

 

Keep in mind that the catch can should be convenient to access. You'll need to check the returns and dump it out occasionally.

[twobone]

I think I may have overfilled the dry sump tank. That might be contributing to the oil smoke.

 

I will put together a catch tank. Thanks bsimon