now i'm nit picking

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puddin

now i'm nit picking

Post by puddin »

got her running like a champ- 60 mile round trips to work and back daily -- sweet

but i noticed oil smell in the car with top up and windows closed- so i used an aftermarket oil vapor breather (cone shaped filter) and it has gotten worse. so i figured out how the smell gets into the car-- the two drains on the firewall that drain out the cowl in front of the windshield seem to be letting the smell into the hvac. so i was gonna plug them but i know they need to drain the rain and moisture that gets into the cowl. so i ran two 5/8" hoses from them to beneath the car (following the frame rail down and cut just prior to the floorboard creating suction. i also covered the cowl vents with felt material to filter the incomming air. but it still smells. so i concluded that there is too much blow by.. i ran compression test and all 4 cyl are 130 psi and motor starts and runs great and dosen't have any oil comsumption problems. but the oil vapor hose just keeps on burping smoke. is this uncommon? should i send it into the air cleaner like it used to be and hook up a vac line to suck it into the eng? i did noticed that the plugs were getting black from all that oil burning on them. i kinda don't want the motor to burn all that oil again -seems to run better just burning gas...

i was thinking of running that oil vapor hose under the car as well like the cowl drains but figure that it will just come back in when the top is down (stationwagon effect).. whatta think anybody else seem to have this problem????
Estaban

Re: now i'm nit picking

Post by Estaban »

since mine is a 850 (rear-engine) there is a little difference here but...

several years ago my dad had that same problem... well the oil vapor fouling the plugs (and everything before the plugs too) so he routed it down to the exhaust system after the muffler. Now it comes out of the exhaust pipe.
mdrburchette
Posts: 5754
Joined: Wed Jan 25, 2006 5:49 am
Your car is a: 1972 Fiat 124 Sport
Location: Winston-Salem, NC

Re: now i'm nit picking

Post by mdrburchette »

You might need to service the cyclonic trap. It may need cleaned out.
1972 124 Spider (Don)
1971 124 Spider (Juan)
1986 Bertone X19 (Blue)
1978 124 Spider Lemons racer
1974 X19 SCCA racer (Paul)
2012 500 Prima Edizione #19 (Mini Rossa)
Ever changing count of parts cars....It's a disease!
majicwrench

Re: now i'm nit picking

Post by majicwrench »

The "oil vapor hose" has got to be run to the air cleaner like the factory did it. Guessing you do not have the factory air filter??
puddin

Re: now i'm nit picking

Post by puddin »

mdrburchette wrote:You might need to service the cyclonic trap. It may need cleaned out.
are u talking about the spring in the tube? seems like the hose isn't restricted at all it blows oily smoke continuously and changes as i throttle up.

also i noticed a caramel milky residue inside the hose-- i suppose its water mixing with oil but no water in crankcase or on dipstick-- could this just be condensation????

not sure how to run into exhuast -- did u actually plumb it into the exhuast - wouldn't the exhuast pressure just overcome the oil vapor and blow exhuast into the crankcase????
Estaban

Re: now i'm nit picking

Post by Estaban »

That is where the 'little difference' is.

I have an 850, they are rear-engine so it's a short trip to the end of the exhaust. It is tied in within four inches of the end of the exhaust pipe.
majicwrench

Re: now i'm nit picking

Post by majicwrench »

It is supposed to be run to the air cleaner, not the exhaust. Old circle track engines we ran crankcase breather to exhaust, and used check valves so it would floow only one way. You then build a little venturi to put in the exhaust and you get a neg pressure that constantly sucks crank vapors. BUT it is supposed to be run to the air cleaner!!
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maytag
Posts: 1789
Joined: Mon Oct 19, 2009 9:22 pm
Your car is a: 1976 124 spider
Location: Rocky Mountains....UTAH! (Not Colorado)

Re: now i'm nit picking

Post by maytag »

let's be clear here: the factory ran it to the air cleaner. There are several reasons for this, the biggest one I'm aware of is that it will then ingest and burn the vapor / fumes that are scavenged from the crankcase. It's an emissions thing. I would point-out though that if you have excessive blow-by, then you'll experience enough oil in the vapor that you'll notice a less complete burn, resulting in lower cylinder pressures, thus lower power and higher emissions from the motor.

One thing that benefits some motors is the slight negetave pressure (vacuum) that can result from venting that to the air cleaner OR the exhaust. Either one will create a negative pressure. In some motors this negative pressure can increase the seal of the rings to the cylinder wall, resulting in higher cylinder pressures and less blow-by. It is more complicated when plumbed to the exhaust, because you must have a one-way valve in place that works with such minimal pressures.

I think either solution is acceptable, whereas venting to atmosphere really is not.

And the suggestion to check your cyclonic trap was a good one. This is not just the spring in the hose. There is a trap that is bolted to the block, and the hose to the air-cleaner comes up from that. The function of the trap is to collect the oil from the vapors and return it to the sump. If it is not working properly, that can cause some further issues.
I'm no Boy-Racer..... but if I can't take every on-ramp at TWICE the posted limit.... I'm a total failure!
puddin

Re: now i'm nit picking

Post by puddin »

i never pulled the cyc trap -- is there any connections to internal engine parts ??? or are there any parts that may fall into the crankcase oil pan if i unbolt and remove the assembly???
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